OCN Basics Flashcards: 140 Practice Questions & Answers

For women in 2026, the ranking for Incidence (new cases) is: 1. Breast, 2. Lung and Bronchus, 3. Colorectal. The ranking for Mortality (deaths) is: 1. Lung and Bronchus, 2. Breast, 3. Colorectal. Rational: While breast cancer is significantly more common, lung cancer remains more lethal due to later-stage detection. Exam Tip: ONCC often tests the difference between most common (incidence) and most deadly (mortality). Note that lung cancer mortality is declining due to LDCT screening and targeted therapies, but it still holds the #1 spot. Clinical Pearl: Lung cancer mortality in women has declined more slowly than in men over the last decade.

In 2026, CRC incidence is increasing by approximately 1-2% annually in adults under 50, while it is decreasing in older adults (65+) due to high screening uptake. Clinical Pearl: This trend led to the guideline change lowering the screening start age to 45 for average-risk individuals. Exam Strategy: Be prepared to identify that younger patients often present with more advanced (Stage III/IV) disease at diagnosis because symptoms are often dismissed as benign (e.g., hemorrhoids). Additionally, rectal cancer is rising faster than colon cancer in the under-50 demographic.

Lung cancer in never-smokers (defined as <100 lifetime cigarettes) is increasingly recognized in 2026, particularly among young Asian and Caucasian females. Adenocarcinoma is the most common histological subtype in this group. Rational: While tobacco cessation has reduced squamous cell carcinoma, environmental factors (radon, pollution) and genetic drivers (EGFR, ALK) are key. Exam Tip: Don't assume a lung cancer patient has a smoking history; the stigma of lung cancer is a common psychosocial topic on the OCN exam.

Hepatocellular Carcinoma (HCC) incidence is increasingly driven by MASLD (formerly NAFLD) and obesity, rather than just Hepatitis B or C. Rational: While antiviral therapies have reduced viral-related HCC, the metabolic syndrome epidemic has shifted the etiology. Clinical Pearl: Liver cancer incidence has risen faster than almost any other cancer in the last two decades. Exam Tip: ONCC focuses on modifiable risk factors; obesity is now linked to at least 13 different types of cancer, with liver and endometrial showing the strongest correlations.

Black/African American men have the highest incidence and mortality rates for prostate cancer. In 2026, the mortality rate remains approximately 2 to 2.5 times higher than that of White men. Rational: This is attributed to a combination of genetic factors, systemic inequities in healthcare access, and later stage at diagnosis. Exam Strategy: Disparities are a high-priority OCN topic. Focus on access to care and screening equity as primary interventions to close this gap. Also, note that Black men are often diagnosed at a younger age.