Cancer Pathophysiology, Prevention and Detection - Cheat Sheet
Your rapid-fire reference guide for the last 30 minutes before the exam. Master carcinogenesis, grading/staging, CAUTION signs, prevention strategies, and Philippines-specific cancer epidemiology.
PATHOPHYSIOLOGY OF CANCER
Important facts
- THREE GENES INVOLVED: proto-oncogenes (accelerator), tumor suppressors (brake), DNA repair genes
- LOSS OF TWO CONTROLS: Cancer needs both activated oncogenes AND inactivated tumor suppressors (Knudson two-hit hypothesis)
- Most common tumor suppressor loss: p53 (the guardian of the genome); loss found in >50% of human cancers
- Carcinogenesis is MULTISTEP: one mutation is not enough; typically 4-7 mutations accumulate over years
- Hallmarks of cancer cells: unlimited replicative potential, evade growth suppressors, resist apoptosis, induce angiogenesis, enable invasion/metastasis, promote inflammation
Key definitions
Neoplasm/Tumor
Example
Lipoma (benign), breast carcinoma (malignant)
An abnormal mass of tissue caused by uncontrolled cell growth; can be benign or malignant.
Contact Inhibition
Example
Normal skin cells stop growing when crowded; cancer cells ignore this signal
Normal cellular property where cells stop dividing when they touch neighboring cells; LOST in cancer.
Apoptosis
Example
Healthy cells die when DNA damage is irreparable; cancer cells bypass this mechanism
Programmed cell death; normal, old, or damaged cells self-destruct; EVADED by cancer cells.
Oncogene
Example
RAS, MYC, HER2 mutations cause uncontrolled growth
Mutated proto-oncogene; acts as a stuck accelerator, driving relentless cell proliferation.
Tumor Suppressor Gene
Example
p53 mutation in Li-Fraumeni syndrome increases cancer risk across multiple organs
Brake gene (e.g., p53, RB); when lost/inactivated, removes growth restraint and apoptosis trigger.
Carcinogen
Example
Tobacco, asbestos, HPV, UV radiation, aflatoxin
Any agent that induces irreversible DNA mutation leading to cancer initiation.
Angiogenesis
Example
A tumor >1-2 mm requires its own blood supply to grow further
Formation of new blood vessels; allows growing tumors to obtain nutrients and oxygen.
Metastasis
Example
Breast cancer spreading to lungs, liver, bone, or brain
Spread of malignant cancer from primary site to distant organs; defines malignancy.
Diagrams to know
- Three stages of carcinogenesis (Initiation → Promotion → Progression)
- Oncogene vs tumor suppressor: accelerator and brake model
- Metastatic spread pathways: direct extension, lymphatic, hematogenous (bloodstream), seeding
CARCINOGENESIS: THREE-STAGE MODEL
Important facts
- INITIATION is IRREVERSIBLE; PROMOTION is REVERSIBLE — prevention window is during promotion phase
- DOSE + DURATION matter: cancer risk is cumulative over years/decades of exposure
- Latency period: 10-40 years between first exposure and cancer diagnosis (why screening focuses on older adults)
- Promoters are NOT necessarily carcinogens themselves but enable carcinogen-transformed cells to grow
- Multiple carcinogens often required: smoking + asbestos, smoking + HPV increase risk synergistically
Key definitions
INITIATION
Example
PAH in tobacco binds to DNA; HPV integrates into cervical epithelial cell DNA
First hit: irreversible DNA mutation from carcinogen exposure; cell is now transformed but dormant.
PROMOTION (REVERSIBLE STAGE)
Example
Chronic smoking, alcohol, hormones, chronic inflammation stimulate growth of initiated cells
Repeated exposure to promoting agents causes initiated cell to proliferate; THIS IS WHERE PREVENTION WORKS.
PROGRESSION
Example
Benign adenoma progresses through dysplasia to invasive carcinoma over years
Established tumor gains malignant traits: angiogenesis, invasion, metastasis; increasingly aggressive.
Diagrams to know
- Timeline of carcinogenesis from initiation through promotion to clinical presentation
CARCINOGENS BY TYPE
Important facts
- TOBACCO is the SINGLE most important modifiable risk factor globally (and in Philippines)
- HPV (human papillomavirus) is the MOST common cause of cancer worldwide via infectious agent
- Hepatitis B and C are major liver cancer risk factors in Philippines due to endemic HBV
- H. pylori infection increases gastric cancer risk 2-3 fold; can be eradicated with antibiotics
- EBV associated with Burkitt lymphoma (endemic in Africa) and nasopharyngeal carcinoma (SE Asia)
Key definitions
Chemical Carcinogens
Example
Polycyclic aromatic hydrocarbons (PAH) in tobacco smoke; asbestos in construction materials
Tobacco, asbestos, benzene, formaldehyde, aflatoxin (contaminated grains); cause DNA mutations.
Physical Carcinogens
Example
UV-B causes melanoma; radon gas increases lung cancer risk in homes
Ultraviolet (UV) radiation and ionizing radiation (X-rays, gamma rays, radon); damage DNA directly.
Infectious Agents (Oncogenic Viruses & Bacteria)
Example
HPV 16/18 → cervical cancer; HBV chronic infection → hepatocellular carcinoma
Viruses: HPV (cervical), HBV/HCV (liver), EBV (Burkitt lymphoma, nasopharyngeal); Bacteria: H. pylori (gastric).
Diagrams to know
- Carcinogens by origin: chemical, physical, infectious
BENIGN vs MALIGNANT TUMORS
Important facts
- Benign tumors NEVER become malignant; they are two distinct pathologic entities
- Benign tumor suffix: -oma (lipoma, fibroma, adenoma); but -oma does NOT always mean benign (melanoma, lymphoma are malignant)
- Malignant carcinomas = epithelial tissue origin; sarcomas = connective/muscle/bone; leukemias/lymphomas = blood-forming tissue
Diagrams to know
- Tissue origin and cancer naming (epithelial → carcinoma, mesenchymal → sarcoma, hematopoietic → leukemia/lymphoma)
INVASION AND METASTASIS
Important facts
- LYMPHATIC SPREAD IS MOST COMMON for carcinomas; explains why lymph node status is critical in staging
- FOUR ORGAN SYSTEMS are most common metastatic sites: lungs (everything's blood passes here), liver (portal circulation), bone (hematopoietic marrow), brain (blood-brain barrier breakdown)
- Metastasis RETAINS CELL TYPE of origin: breast cancer spreading to bone is BREAST CANCER, not bone cancer (still graded/treated as breast cancer)
- Blood vessels in tumor tissue are ABNORMAL and LEAKY: enhances hematogenous spread
- Cancer cells must undergo EPITHELIAL-MESENCHYMAL TRANSITION (EMT) to detach and invade; then MESENCHYMAL-EPITHELIAL TRANSITION (MET) to re-establish at new site
Key definitions
Direct Extension (Local Invasion)
Example
Stomach cancer extending through gastric wall into adjacent liver or pancreas
Cancer invades adjacent tissues by breaking through normal tissue boundaries.
Lymphatic Spread
Example
Breast cancer → axillary lymph nodes → supraclavicular nodes → systemic spread
Cancer cells enter lymphatic vessels; spread to regional lymph nodes first, then distant nodes. MOST COMMON route for carcinomas.
Hematogenous Spread (Bloodstream)
Example
Colon cancer → portal vein → liver; any cancer → lungs (everyone's blood passes through lungs)
Cancer cells enter blood vessels; travel through circulation to distant organs.
Seeding (Transcoelomic Spread)
Example
Ovarian cancer spreading throughout peritoneal cavity; lung cancer seeding pleural space
Cancer cells spread across body cavities (peritoneal, pleural, pericardial).
Diagrams to know
- Four pathways of metastatic spread
- Seed and soil hypothesis: cancer cell (seed) requires receptive tissue microenvironment (soil)
GRADING vs STAGING (DO NOT CONFUSE)
Important facts
- GRADING = microscopic (pathologist's opinion); STAGING = macroscopic (radiologist + surgeon's opinion)
- Grading DOES NOT change; staging CAN change if new metastases discovered
- HIGH GRADE + EARLY STAGE = paradox: aggressive tumor found early (good prognosis with treatment)
- LOW GRADE + LATE STAGE = paradox: slow tumor found late (poor prognosis despite low aggressiveness)
- Grade and stage are INDEPENDENT: no direct correlation between them
Key definitions
GRADING
Example
Grade 1 = well differentiated (looks like normal tissue); Grade 4 = anaplastic (looks nothing like normal)
CELLULAR APPEARANCE only; how abnormal/undifferentiated cancer cells look under microscope (Grade 1-4); PROGNOSIS indicator.
STAGING
Example
Stage I = early, localized; Stage IV = advanced with distant metastasis
ANATOMIC EXTENT of disease in body; how much cancer is present and how far it has spread (TNM; Stage 0-IV); TREATMENT GUIDE.
Diagrams to know
- Grade 1-4 spectrum of differentiation
- Stage 0-IV progression and TNM components
TNM STAGING SYSTEM (THE GOLD STANDARD)
Common values
Value
Malignant cells confined to epithelial layer of origin; NO invasion into basement membrane
Symbol
Tis = Stage 0 (most curable)
Quantity
Carcinoma in situ (Tis) definition
Important facts
- TNM COMBINES into OVERALL STAGE: Stage 0 (Tis N0 M0), Stage I-III (increasing T/N with M0), Stage IV (any M1)
- M1 (distant metastasis) = AUTOMATIC Stage IV = most aggressive, palliative care focus
- Each cancer type has its OWN TNM definitions: T size cutoffs differ by organ (breast T1 ≤2cm vs colon T1 = submucosa invasion)
- NODAL STAGING is CRITICAL: involved nodes = worse prognosis; sentinel lymph node biopsy identifies first-line nodes
- Re-staging can occur post-treatment if new findings emerge; original (clinical) stage vs pathologic stage after surgery
Key definitions
T (Tumor)
Example
T1 = ≤2 cm (varies by tumor type); T4 = invasion into adjacent structures
Size and local extent of primary tumor: Tis (carcinoma in situ, confined to origin layer), T1-T4 (increasing size/invasion).
N (Nodes)
Example
N0 = no lymph node involvement; N3 = extensive regional nodal spread
Regional lymph node involvement: N0 (no nodes), N1-N3 (increasing number/extent of nodal spread).
M (Metastasis)
Example
M0 = cancer confined to organ of origin + regional nodes; M1 = lung/liver/bone/brain spread = incurable stage
Presence/absence of distant metastasis: M0 (no distant spread), M1 (distant metastasis present).
Diagrams to know
- TNM components and how they combine into overall stage (0-IV)
CANCER WARNING SIGNS: CAUTION MNEMONIC
Important facts
- C = Change in BOWEL OR BLADDER HABITS: constipation, diarrhea, urinary frequency/urgency
- A = A SORE THAT DOES NOT HEAL: oral ulcers, skin lesions, genital sores persisting >3 weeks
- U = UNUSUAL BLEEDING OR DISCHARGE: hemoptysis (lung), hematuria (bladder/kidney), vaginal bleeding (cervical), bloody discharge (breast/GI)
- T = THICKENING OR LUMP: palpable mass in breast, lymph nodes, skin; any new enlargement
- I = INDIGESTION OR DIFFICULTY SWALLOWING: dysphagia (esophageal), persistent epigastric discomfort (gastric)
- O = OBVIOUS CHANGE IN WART OR MOLE: color change, irregular borders, size growth, itching, bleeding
- N = NAGGING COUGH OR HOARSENESS: persistent cough >3 weeks (lung), hoarseness (laryngeal), voice change
- KEY: Duration > 3 weeks + persistence despite standard treatment = RED FLAG for malignancy evaluation
Key definitions
CAUTION (American Cancer Society Seven Warning Signs)
Example
A non-healing sore on lip for 3 weeks → evaluate for oral cancer
Mnemonic for persistent symptoms that warrant cancer evaluation; any single sign lasting weeks demands medical workup.
Diagrams to know
- CAUTION mnemonic with each letter's corresponding warning sign
PRIMARY PREVENTION (STOP CANCER BEFORE IT STARTS)
Important facts
- TOBACCO CESSATION: Single most important intervention globally; reduces lung, oral, esophageal, bladder, pancreatic cancer risk
- Secondhand smoke is carcinogenic: passive smoking increases non-smoker's lung cancer risk 20-30%
- ALCOHOL LIMITATION: >2 drinks/day increases breast, esophageal, laryngeal, liver cancer risk; synergistic with tobacco
- SUN PROTECTION: SPF ≥30 sunscreen, protective clothing, avoid peak hours (10am-4pm) prevents melanoma and non-melanoma skin cancers
- DIET: High-fiber (30g/day), abundant fruits/vegetables (5+ servings), low red/processed meat, low salt-cured foods reduces colorectal, gastric, breast cancer
- WEIGHT MANAGEMENT: Obesity increases breast (postmenopausal), endometrial, colorectal, pancreatic, kidney cancer risk via insulin, estrogen
- PHYSICAL ACTIVITY: ≥150 min/week moderate activity reduces colorectal, breast, endometrial cancer risk
- HPV VACCINATION (Gardasil, Cervarix): Prevents cervical, vulvar, anal, oropharyngeal cancers; best given ages 11-12 (pre-sexual activity); now approved to age 45
- HEPATITIS B VACCINATION: Prevents HBV-related hepatocellular carcinoma; mandatory in PH newborn schedule
- OCCUPATIONAL SAFETY: Asbestos, benzene, formaldehyde monitoring in workplace; personal protective equipment
Key definitions
Primary Prevention
Example
Smoking cessation, sun protection, HPV vaccination
Eliminate or reduce exposure to carcinogens so cancer NEVER develops; occurs during promotion phase.
Diagrams to know
- Modifiable vs non-modifiable risk factors for cancer
- Steps of primary prevention (remove carcinogen, reduce dose, use PPE)
SECONDARY PREVENTION (DETECT CANCER EARLY)
Important facts
- BREAST CANCER SCREENING: Monthly self-exam (BSE) starting age 20; clinical breast exam (CBE) annually; mammography starting age 40-50 (varies by guidelines)
- CERVICAL CANCER SCREENING: Pap smear every 3 years (age 21-65) or HPV co-testing every 5 years; colposcopy if abnormal
- COLORECTAL CANCER SCREENING: Fecal occult blood test (FOBT) annually, sigmoidoscopy every 5 years, OR colonoscopy every 10 years (starting age 45-50)
- PROSTATE CANCER SCREENING: PSA blood test + digital rectal exam (DRE); controversial due to overdetection; discuss risks/benefits with patient
- TESTICULAR CANCER SCREENING: Monthly testicular self-exam (TSE) in males ages 15-40; palpate for lumps, firmness, size change
- SKIN CANCER SCREENING: Monthly self-inspection using ABCDE rule; professional skin exam for high-risk individuals
- LUNG CANCER SCREENING: Low-dose CT chest for high-risk smokers (≥30 pack-years); not recommended for low-risk
- SCREENING ACCURACY: Sensitivity (detects true disease), specificity (rules out false positives), positive/negative predictive values guide test selection
- OVERDETECTION RISK: Screening may identify cancers that wouldn't have caused death (indolent tumors); requires shared decision-making
Key definitions
Secondary Prevention
Example
Mammography, Pap smear, colonoscopy, PSA testing
Detect cancer in early stages when most curable via screening and early detection; requires asymptomatic testing.
Diagrams to know
- ABCDE rule for melanoma (Asymmetry, Border irregularity, Color variation, Diameter >6mm, Evolving/changing)
SELF-EXAMINATION TECHNIQUES
Important facts
- BSE TIMING: Best 1 week after menses when breast engorgement subsides; postmenopausal women: same date monthly
- BSE POSITIONS: Inspect in mirror with arms at sides, raised, hands behind head; palpate standing in shower and lying down
- TSE TECHNIQUE: Roll each testicle between thumb and fingers; compare size/firmness; report lumps, pain, or swelling immediately
- SKIN INSPECTION: Use hand mirror for back/scalp; photograph baseline moles for future comparison; monitor for change over time
- RED FLAGS IN SELF-EXAM: New lump, bloody discharge, persistent rash, mole changing color/size/shape
Key definitions
Breast Self-Examination (BSE)
Example
Visual inspection for dimpling/asymmetry; palpation in quadrants and axillae for masses, discharge
Monthly palpation of breast tissue by patient; timing: 1 week after menstrual period begins (breast less tender).
Testicular Self-Examination (TSE)
Example
Palpate each testicle gently for lumps, firmness, size asymmetry; report any change to provider
Monthly palpation after warm shower when scrotum relaxed; best performed age 15-40.
Skin Self-Inspection (ABCDE Rule)
Example
ABCDE: Asymmetry (halves don't match), Border (irregular/ragged), Color (multiple colors), Diameter (>6mm = suspicious), Evolving (changes over weeks)
Monthly inspection of moles and skin lesions using ABCDE criteria.
Diagrams to know
- BSE hand positions (inspection and palpation stances)
- TSE palpation technique
DIAGNOSTIC TESTS FOR CANCER
Important facts
- BIOPSY IS MANDATORY for cancer diagnosis: imaging and markers suggest malignancy but cannot confirm it
- TUMOR MARKERS ARE NOT SCREENING TOOLS: elevated marker ≠ cancer diagnosis; must have clinical + imaging correlation
- PSA (prostate-specific antigen) elevated in BPH and prostatitis, not cancer-specific; PSA >4 ng/mL warrants further investigation
- CA-125 (cancer antigen 125) elevated in ovarian cancer but also in benign conditions (endometriosis, fibroids, peritonitis)
- CEA (carcinoembryonic antigen) used post-treatment to monitor colorectal cancer recurrence
- AFP (alpha-fetoprotein) elevated in hepatocellular carcinoma and testicular cancer; also in benign liver disease
- HCG (human chorionic gonadotropin) in testicular cancer (choriocarcinoma); always run in male gonadal tumors
- PET SCAN uses glucose metabolism: cancer cells consume more glucose than normal tissue (18F-FDG PET); useful for staging/restaging
Key definitions
BIOPSY (Gold Standard)
Example
Needle biopsy (fine-needle, core), incisional (partial removal), excisional (complete removal with margins)
Tissue removal for histopathologic diagnosis; only definitive way to confirm malignancy.
Tumor Markers (Biomarkers)
Example
PSA (prostate), CA-125 (ovarian), CEA (colorectal), AFP (liver/testicular), HCG (testicular/gestational trophoblastic)
Substances in blood/body fluids elevated in cancer; used for prognosis, monitoring treatment response, detecting recurrence; NOT for initial diagnosis.
Imaging Studies
Example
CT chest/abdomen for staging lung cancer; MRI brain for brain metastases
Visualize tumor size, extent, and metastases: X-ray, CT, MRI, ultrasound, PET scan.
Endoscopy
Example
Colonoscopy (colon), gastroscopy (stomach), bronchoscopy (lung)
Direct visualization of internal organs via scope; allows biopsy of suspicious lesions.
Diagrams to know
- Diagnostic algorithm: imaging → biopsy → histology → staging
CANCER EPIDEMIOLOGY IN THE PHILIPPINES
Common values
Value
~150,000-160,000
Symbol
Based on WHO/GLOBOCAN 2020
Quantity
Estimated annual new cancer cases in Philippines
Value
~100,000+
Symbol
Approximately 2 in 3 patients diagnosed with advanced disease
Quantity
Estimated annual cancer deaths in Philippines
Important facts
- LEADING CANCERS IN PHILIPPINES (in order): Breast (most common overall, #1 in women), Lung, Colorectal, Liver, Cervical, Prostate
- BREAST CANCER: #1 cancer in Filipino women; incidence rising due to lifestyle changes (obesity, hormones); delayed diagnosis common
- LUNG CANCER: #1 in Filipino men; strong association with tobacco use (smoking prevalence ~25% in men, 6% in women); also linked to indoor air pollution
- LIVER CANCER (Hepatocellular carcinoma): High incidence due to endemic HBV (hepatitis B vaccination now mandatory to reduce); HCV also a factor
- CERVICAL CANCER: Preventable via HPV vaccination; high incidence in PH due to limited screening access and HPV prevalence; ranks 2nd in women
- COLORECTAL CANCER: Rising incidence; linked to diet, obesity, sedentary lifestyle; late-stage diagnosis common
- PROSTATE CANCER: #2 most common in men (after lung); often asymptomatic until advanced
- NASOPHARYNGEAL CARCINOMA: More common in Philippines than Western countries; associated with EBV, salted fish consumption, genetic predisposition
Key definitions
Incidence
Example
Philippines: ~150,000 new cancer cases annually (2020 estimates)
Number of NEW cancer cases per 100,000 population per year in a geographic region.
Prevalence
Example
Living cancer survivors in Philippines: >600,000
Total number of cancer cases (new + existing) at a given time point.
Diagrams to know
- Top 5-6 cancers in Philippines ranked by incidence
PHILIPPINE CANCER POLICY & NURSING ROLE
Important facts
- RA 11215 mandates DOH leadership in cancer control; integrates prevention, detection, treatment, and survivorship services
- Philippine Health Insurance Corp (PhilHealth) provides coverage for cancer screening and treatment under UHC
- Nurses are PRIMARY ADVOCATES: educate on risk factors, promote screening, support diagnostic workup, reduce fatalism
- CULTURAL SENSITIVITY REQUIRED: Many Filipino patients have fatalistic beliefs about cancer ('cancer = death'); family-centered decision-making critical
- Community health workers (barangay health workers/BHWs) and nurses drive grassroots prevention education and screening promotion
- HPV vaccine (school-based) and HBV vaccine (birth dose) programs reduce cervical and liver cancer incidence
- Limited access to early detection in rural areas: telemedicine, mobile screening clinics, and nurse-led education programs help bridge gap
Key definitions
Republic Act 11215 (NICCA - National Integrated Cancer Control Act of 2019)
Example
Created Cancer Assistance Fund; mandated DOH to develop cancer control strategies; requires cancer registries
Philippine law establishing comprehensive national cancer control program addressing prevention, early detection, treatment, survivorship, and financial protection.
Cancer Assistance Fund
Example
Eligible patients receive subsidy for chemotherapy, radiation, surgery at DOH-accredited centers
Government fund to provide financial support for cancer patients unable to afford treatment in accredited facilities.
Diagrams to know
- Philippine cancer control framework under NICCA
- Nurse's role in cancer prevention and detection continuum
NURSING MANAGEMENT & PATIENT EDUCATION
Important facts
- PSYCHOLOGICAL SUPPORT IS CRITICAL: Cancer diagnosis triggers fear, grief, loss of control; screening anxiety delays care
- FAMILY INVOLVEMENT: In Philippines, family (especially spouse, parents) drives health decisions; include them in teaching/counseling
- ADDRESS CULTURAL BELIEFS: Some Filipino patients view cancer as punishment, hereditary curse, or fate; reframe as preventable/treatable
- BARRIER IDENTIFICATION: Cost, transportation, work loss, language, health literacy; develop problem-solving strategies with patient
- CONTINUITY OF CARE: Follow up on screening results; ensure timely referral for abnormalities; track appointment adherence
- ADVOCACY: Nurse connects patients to DOH services, Cancer Assistance Fund, support groups, counseling resources
- SELF-CARE PROMOTION: Teach self-exams, lifestyle modifications, stress management, sleep hygiene during diagnostic wait
Key definitions
Health Promotion (Cancer Prevention Education)
Example
Smoking cessation counseling, sun safety teaching, HPV vaccination education
Nursing intervention targeting modifiable risk factors to prevent cancer initiation and promotion.
Screening Facilitation
Example
Explain Pap smear procedure, coordinate mammogram appointment, teach TSE
Nurse arranges and supports age-appropriate cancer screening; addresses barriers (cost, transportation, knowledge, fear).
Diagnostic Support
Example
Prepare patient for biopsy; explain results; connect to support services
Nurse reinforces explanations, manages anxiety during diagnostic workup, allows emotional expression.
Diagrams to know
- Nursing process in cancer prevention/detection: assess → diagnose → plan → implement → evaluate
- Barriers to screening and nursing interventions to overcome them
Must remember
- CANCER = uncontrolled cell proliferation with LOSS OF CONTACT INHIBITION + FAILURE OF APOPTOSIS; driven by activated ONCOGENES (stuck accelerator) and inactivated TUMOR SUPPRESSORS like p53 (missing brakes). Two-hit hypothesis: both oncogenes AND tumor suppressors must be disrupted.
- CARCINOGENESIS IS MULTISTEP: Initiation (irreversible mutation by carcinogen) → Promotion (reversible, repeated exposure to promoters = PREVENTION WINDOW) → Progression (angiogenesis, invasion, metastasis). Prevention works during PROMOTION phase by removing exposures.
- METASTASIS (spread) most commonly via LYMPHATIC SYSTEM; hematogenous (blood) is second. Four organ sites: LUNGS (most common; all blood passes through), LIVER, BONE, BRAIN. Metastatic cancer KEEPS CELL TYPE of primary (breast cancer in bone = BREAST cancer, not bone cancer).
- CAUTION WARNING SIGNS (memorize exactly): Change in bowel/bladder habits, A sore that doesn't heal, Unusual bleeding/discharge, Thickening/lump, Indigestion/dysphagia, Obvious change in wart/mole, Nagging cough/hoarseness. Any sign >3 weeks = medical evaluation.
- GRADING ≠ STAGING. GRADE = microscopic appearance (1=well diff/least aggressive, 4=anaplastic/most aggressive); PROGNOSIS. STAGE = anatomic extent (TNM; 0=carcinoma in situ, IV=distant metastasis); TREATMENT GUIDE. Independent variables; high grade + early stage ≠ poor prognosis.
- TNM SYSTEM: T (tumor size/local invasion: Tis=carcinoma in situ, T1-T4 increasing), N (nodal involvement: N0=none, N1-N3 increasing), M (metastasis: M0=none, M1=distant spread). M1 = automatic Stage IV = incurable. Biopsy is ONLY definitive diagnostic test.
- PRIMARY PREVENTION (stop cancer before it starts): Tobacco cessation #1 modifiable risk factor; sun protection; HPV vaccination (cervical cancer); hepatitis B vaccination (liver cancer); alcohol limitation; healthy diet/weight/activity. SECONDARY PREVENTION (detect early): Mammography, Pap smear, colonoscopy, PSA, self-exams (breast, testicular, skin ABCDE rule).
- BENIGN vs MALIGNANT: Benign = encapsulated, well-differentiated, slow growth, NO metastasis, rare recurrence (-oma suffix). Malignant = invasive (NO capsule), poorly differentiated/anaplastic, rapid growth, METASTASIZES, recurs after removal (carcinoma/sarcoma/leukemia/lymphoma). Malignancy = ability to metastasize.
- PHILIPPINES CANCER EPIDEMIOLOGY: Leading cancers = BREAST (women), LUNG (men; smoking), COLORECTAL, LIVER (HBV endemic), CERVICAL (HPV). RA 11215 (NICCA 2019) establishes national cancer control; DOH leads; Cancer Assistance Fund for patients. Nurses: educate, screen, address cultural fatalism, involve family.
- NURSING PRIORITIES: (1) Health education on modifiable risk factors + CAUTION signs; (2) Facilitate age-appropriate screening (overcome barriers); (3) Support diagnostic workup (address psychological crisis); (4) Teach self-exams (breast, testicular, skin); (5) Connect to DOH services/support. Family-centered care essential in Philippines; address cultural beliefs that cancer = death/fate.
Last minute tips
- EXAM TRAP: 'Tumor marker elevated = cancer diagnosis' is WRONG. Markers suggest malignancy but BIOPSY ONLY confirms. Tumor markers mainly monitor treatment response/recurrence, not initial diagnosis. PSA, CA-125, CEA, AFP all elevated in benign conditions too.
- METASTASIS DESTINATION: Think 'LLBB' (Lungs, Liver, Bone, Brain) — these are the 4 most common sites. Lungs are #1 because all blood passes through them. Always mention lymph nodes as first stop for lymphatic spread before distant organs.
- GRADING vs STAGING CONFUSION: Quick mental trick: Grade = microscopic (pathologist, looks at cells), Stage = macroscopic (surgeon/radiologist, looks at whole body with imaging). Both predict prognosis but independently — don't try to correlate them.
- CARCINOMA IN SITU (Tis): This is NOT invasive cancer yet; it's confined to the epithelial layer of origin with NO basement membrane breach. Stage 0; most curable (>95% 5-year survival); explains why colonoscopy/Pap smear catch polyps/dysplasia early.
- SECONDARY PREVENTION = SCREENING for ASYMPTOMATIC people. If patient has symptoms (bleeding, lump, persistent cough), that's diagnostic workup, not screening. Don't confuse screening tests with diagnostic tests; screening is population-based, diagnosis is symptom-driven.
Comparison tables
BENIGN vs MALIGNANT TUMORS (EXAM FAVORITE)
| Characteristic | BENIGN | MALIGNANT |
|---|---|---|
| Growth Rate | Slow, self-limited | Rapid, uncontrolled |
| Cell Differentiation | Well differentiated (looks like normal) | Poorly differentiated/anaplastic (looks abnormal) |
| Capsule | Usually encapsulated, well-demarcated | NO capsule, invasive into surrounding tissue |
| Metastasis | DOES NOT metastasize | Metastasizes to distant organs |
| Recurrence Rate | Rare after complete removal | Common, especially if not completely removed |
| Effect on Host | Usually harmless (unless pressure on vital structure) | Often life-threatening; progressive if untreated |
| Naming Convention | -oma suffix (lipoma, adenoma) | Carcinoma (epithelial), sarcoma (mesenchymal), leukemia/lymphoma (hematopoietic) |
| Mitotic Activity | Low, normal mitoses | High, abnormal mitotic figures |
| Local Tissue Destruction | Rarely destroys normal tissue | Destroys and invades normal tissue |
| Bleeding/Necrosis | Rare | Common (due to rapid growth and poor blood supply) |
GRADING vs STAGING (CRITICAL DISTINCTION)
| Aspect | GRADING (Grade 1-4) | STAGING (TNM; Stage 0-IV) |
|---|---|---|
| What it Assesses | MICROSCOPIC appearance only; cellular differentiation | ANATOMIC extent of disease in body; spread status |
| Who Determines | Pathologist examining tissue under microscope | Oncology team (surgeon, radiologist, oncologist) using clinical + imaging data |
| Purpose | Indicates tumor aggressiveness/prognosis | Guides treatment type and intensity; predicts survival |
| Grade 1 / Stage I | Well-differentiated, least aggressive | Early, localized cancer, not spread |
| Grade 4 / Stage IV | Anaplastic, highly aggressive | Advanced with distant metastasis, incurable |
| Does it Change? | No; determined at diagnosis by pathology | Yes; can change if new metastases found (restaging) |
| Paradox Example | Grade 4 + Stage I = aggressive tumor caught early (treatable) | Grade 1 + Stage IV = indolent tumor spread widely (poor prognosis) |
| Used in Prognosis | Yes; high grade = worse prognosis | Yes; high stage = worse prognosis; Stage IV nearly always fatal |
TNM COMPONENTS & WHAT THEY MEAN
| Component | Tis / T0-T1-T2-T3-T4 | N0 / N1-N2-N3 | M0 / M1 |
|---|---|---|---|
| Tis (Carcinoma In Situ) | Malignant cells CONFINED to epithelial layer of origin; NO invasion through basement membrane; Stage 0 (most curable) | N/A | N/A |
| T1-T4 | T1 = smallest invasive tumor; T4 = largest with adjacent structure invasion; size cutoffs vary by organ | N/A | N/A |
| N0 | N/A | NO regional lymph node involvement; best prognosis from nodal perspective | N/A |
| N1-N3 | N/A | N1 = minimal nodal spread; N3 = extensive nodal involvement; worsening prognosis | N/A |
| M0 | N/A | N/A | NO distant metastasis; cancer confined to organ + regional nodes; can be curable with aggressive treatment |
| M1 (AUTOMATIC STAGE IV) | N/A | N/A | DISTANT metastasis present (lung, liver, bone, brain); incurable; prognosis weeks to 1-2 years; palliative care focus |
COMMON CANCER SCREENING TESTS (EXAM ESSENTIAL)
| Cancer Type | Screening Test | Age to Start | Interval | Action on Abnormal Result |
|---|---|---|---|---|
| BREAST (Women) | Monthly BSE + Clinical exam + Mammography | BSE age 20; Clinical exam/Mammo age 40-50 | BSE monthly; Clinical exam annual; Mammo yearly/biennial | Abnormal mammo → ultrasound/biopsy |
| CERVICAL (Women) | Pap smear (or HPV co-testing) | Age 21 | Every 3 years (Pap) or 5 years (HPV co-test) | Abnormal Pap → colposcopy + biopsy |
| COLORECTAL | FOBT (fecal occult blood test), sigmoidoscopy, or colonoscopy | Age 45-50 | FOBT annual; Sigmoidoscopy every 5 years; Colonoscopy every 10 years | Positive FOBT/abnormal scope → colonoscopy + biopsy |
| PROSTATE (Men) | PSA blood test + Digital rectal exam (DRE) | Age 50 (or 40-45 if high risk) | Annually if PSA trend monitored | PSA >4 ng/mL or rising → urology referral, biopsy if indicated |
| TESTICULAR (Men) | Monthly testicular self-examination (TSE) | Age 15 | Monthly self-exam | Lump/firmness/size change → urology evaluation, ultrasound, tumor markers |
| SKIN (All) | Monthly self-inspection (ABCDE rule) + professional skin exam | Age 18 (start baseline); increase age 40+ | Monthly self-check; Professional exam annually for high-risk | Suspicious mole → dermatology, possible biopsy/excision |
| LUNG (High-risk smokers) | Low-dose CT (LDCT) chest | Age 50-80 with ≥30 pack-year smoking history | Annually if high-risk | Abnormal CT → follow-up imaging/biopsy per protocol |
CARCINOGEN TYPES & EXAMPLES
| Carcinogen Class | Mechanism | Examples | Associated Cancers |
|---|---|---|---|
| CHEMICAL | Direct DNA damage; metabolite activation | Tobacco, asbestos, benzene, formaldehyde, aflatoxin, PAH (polycyclic aromatic hydrocarbons) | Lung, oral, esophageal, bladder, mesothelioma, liver, leukemia |
| PHYSICAL (Radiation) | Direct DNA strand breaks; ionization/free radical damage | UV-B/UV-A (solar), X-rays, gamma rays, radon gas, nuclear exposure | Melanoma, non-melanoma skin cancer, leukemia, thyroid, lung |
| INFECTIOUS VIRUSES | Viral oncoproteins disrupt cell cycle (HPV E6/E7 inactivate p53/RB); chronic inflammation | HPV 16/18, Hepatitis B/C, Epstein-Barr virus (EBV), HTLV-1, HHV-8, KSHV, Merkel cell polyomavirus | Cervical/anal/oropharyngeal (HPV), liver (HBV/HCV), Burkitt lymphoma/nasopharyngeal (EBV), ATLL (HTLV), Kaposi sarcoma (HHV-8) |
| INFECTIOUS BACTERIA | Chronic inflammation; bacterial toxins damage epithelium | Helicobacter pylori | Gastric (adenocarcinoma and MALT lymphoma) |
| HORMONAL/ENDOGENOUS | Prolonged hormone receptor stimulation; hyperplasia, dysplasia | Estrogen (unopposed), testosterone, insulin (obesity), thyroid hormones | Breast, endometrial, prostate, colorectal, thyroid |
TUMOR MARKERS: WHICH MARKER FOR WHICH CANCER
| Tumor Marker | Cancer(s) Associated | Use in Practice | Caution/Limitations |
|---|---|---|---|
| PSA (Prostate-Specific Antigen) | Prostate cancer | Screening (PSA >4 ng/mL warrants DRE/urology referral); monitoring treatment response and recurrence | Also elevated in BPH and prostatitis; NOT cancer-specific; can result in overdiagnosis; discuss screening risks/benefits with patient |
| CA-125 | Ovarian cancer (most common) | Screening (controversial), monitoring treatment response, early detection of recurrence | Elevated in many benign conditions (endometriosis, fibroids, peritonitis, menstruation); used with imaging/clinical findings |
| CEA (Carcinoembryonic Antigen) | Colorectal cancer (most common); also gastric, pancreatic, lung | Baseline before treatment; monitoring post-treatment for recurrence (rising CEA suggests relapse) | Elevated in smokers, cirrhosis, inflammatory bowel disease; NOT used for initial diagnosis; sensitivity/specificity limited |
| AFP (Alpha-Fetoprotein) | Hepatocellular carcinoma (HCC); testicular cancer (germ cell tumors) | HCC surveillance in high-risk patients (HBV/HCV); testicular tumor diagnosis and monitoring | Also elevated in benign liver disease, pregnancy, ataxia-telangiectasia; must correlate with imaging (ultrasound/CT for HCC) |
| HCG (Human Chorionic Gonadotropin) | Testicular cancer (choriocarcinoma, seminoma); gestational trophoblastic disease | Diagnosis of testicular cancer (always order in male gonadal tumors); monitoring treatment response | Can be elevated in pregnancy; standardly ordered with AFP in any male gonadal mass |
| CA 19-9 | Pancreatic cancer; also gastric, biliary, colorectal | Monitoring pancreatic cancer treatment response and recurrence; NOT for screening | Elevated in benign GI disease, pancreatitis; not sensitive/specific enough for early diagnosis |
Diagrams
Cancer Pathophysiology: Carcinogenesis & Key Concepts
Comprehensive overview of cancer development, from normal cell regulation breakdown through carcinogenesis stages to metastatic routes. Shows relationship between gene mutations (oncogenes/suppressors) and loss of cellular controls. Highlights the three-stage carcinogenesis model and metastasis pathways.
Cancer Screening & Early Detection Pathway (Secondary Prevention)
Decision tree showing the secondary prevention pathway from screening through diagnosis to treatment. Illustrates negative vs abnormal screening results, the necessity of biopsy for definitive diagnosis, and the nurse's central role in facilitating access and education throughout the process.
TNM Staging & Stage Progression (Cancer Extent)
State diagram showing progression from carcinoma in situ (Stage 0) through Stages I-III based on increasing tumor size (T), nodal involvement (N), and finally Stage IV with distant metastasis (M1). Emphasizes that M1 = automatic Stage IV = incurable, and that early detection at Stage 0-I significantly improves prognosis.
CAUTION Warning Signs & Nursing Assessment
Assessment flowchart for the seven CAUTION warning signs. Each branch represents one of the mnemonic letters with specific symptoms to assess. Shows the critical 3-week duration rule and decision point for referral, emphasizing the nurse's role in early identification and patient support through diagnostic workup.