ABS CGSO cheat sheet

Tissue diagnosis is required before most definitive therapy; exceptions include emergencies such as spinal cord compression and some radiographically diagnostic tumors (e.g., typical HCC in cirrhosis).

TNM staging: T = primary tumor extent, N = regional nodes, M = distant metastasis; prefix c = clinical, p = pathologic, y = post-neoadjuvant, r = recurrent.

Grade describes differentiation (e.g., G1 well to G4 undifferentiated); stage and grade are independent prognostic axes and both must be reported.

Carcinoma of unknown primary: immunostains (CK7/CK20, TTF-1, CDX2, PAX8, GATA3) plus clinical pattern guide the likely origin; ~80% remain without an identified primary.

Paraneoplastic syndromes (SIADH, hypercalcemia, Cushing, Lambert-Eaton) can be the presenting feature and may precede the primary tumor by months.

Rare tumor examples: GIST (KIT/CD117, DOG1), desmoid fibromatosis (beta-catenin), NUT midline carcinoma (NUT rearrangement), and adrenocortical carcinoma.

Liquid biopsy (circulating tumor DNA) is used for genotyping when tissue is insufficient and for minimal residual disease monitoring; a negative result does not exclude cancer.

Diagnostic error is reduced by second-review of pathology for rare or ambiguous tumors and by multidisciplinary tumor board review before treatment.

Multidisciplinary tumor board integrates surgical, medical, radiation oncology, pathology, radiology, and supportive care input into a documented plan.

Neoadjuvant therapy is given before surgery to downstage or test biology; adjuvant therapy is given after macroscopically complete resection to reduce recurrence risk.

Multimodality sequencing matters: concurrent chemoradiation is standard for locally advanced head/neck, cervical, and lung cancers; full-dose systemic therapy between radiation fractions can increase toxicity.

Treatment intent must be explicitly stated: curative, disease control/palliative, or purely symptomatic; intent drives choice of regimen and toxicity tolerance.

Performance status (ECOG 0-4, Karnofsky 0-100) and comorbidity predict treatment tolerance and are used to select intensive vs. reduced regimens.

Fertility preservation counseling should occur before gonadotoxic therapy; options include sperm banking, oocyte/embryo cryopreservation, and ovarian transposition.

Geriatric oncology assessment (function, cognition, nutrition, polypharmacy, falls) modifies treatment intensity in older adults more than chronologic age.

Clinical trials should be offered as a standard option where available; eligibility depends on organ function, prior therapy, and molecular profile.

Cancer rehabilitation is delivered across the continuum: prehabilitation before surgery, inpatient rehabilitation during acute treatment, and outpatient/survivorship rehabilitation after.

Lymphedema risk rises after axillary or inguinal node dissection and regional radiation; management includes compression, manual lymphatic drainage, and exercise.

Cancer-related fatigue is treated with graded aerobic and resistance exercise plus sleep and psychosocial interventions; rest alone worsens deconditioning.

Chemotherapy-induced peripheral neuropathy increases fall risk; balance training and gait aids reduce falls and improve function.

Bone metastases and myeloma carry pathologic fracture risk; load-bearing exercise should be modified and weight-bearing status clarified with the treating team.

Head and neck cancer rehabilitation includes swallowing therapy, trismus exercises, speech therapy, and shoulder mobility after neck dissection.

Brain tumor rehabilitation addresses cognitive deficits, hemiparesis, and seizure precautions; cognitive rehabilitation and caregiver training improve function.

Return-to-work and vocational rehabilitation should be addressed during survivorship; fatigue, neuropathy, and cognitive change are common barriers.

Primary prevention reduces exposure or risk: HPV and HBV vaccination, smoking cessation, sun protection, alcohol reduction, and weight/activity interventions.

Secondary prevention is screening: cervical cytology/HPV testing, mammography, colorectal screening (colonoscopy or stool tests), and lung LDCT in high-risk smokers.

Screening harms include false positives, overdiagnosis, and procedure complications; benefit depends on pretest probability and life expectancy.

Hereditary cancer syndromes (BRCA1/2, Lynch syndrome, FAP, Li-Fraumeni) require genetic counseling, cascade testing, and syndrome-specific surveillance.

Outreach aims to reduce disparities: patient navigation, community health workers, mobile screening units, and culturally tailored education improve uptake.

Research designs: randomized controlled trials for efficacy, observational cohort studies for risk factors, and implementation science for translating evidence into practice.

Informed consent for research must cover purpose, risks, benefits, alternatives, confidentiality, and the voluntary right to withdraw.

Equipoise and independent ethics review (IRB) govern human-subjects research; vulnerable populations require additional protections.