Cancer Risk Factors and Lung Cancer Screening

Introduction

• Source: American Cancer Society's Journal, Cancer: A Cancer Journal for Clinicians
• Study Title: Proportion and Number of Cancer Cases and Deaths Attributable to Potentially Modifiable Risk Factors in the United States in 2019
• Objective: Identify risk factors for cancer and the proportion of cases due to these risk factors

Key Findings

• Overall Impact: 40% of all cancers in the US are attributable to modifiable risk factors.
• Primary Risk Factor: Cigarette smoking accounts for nearly half of all attributable cancer cases.

Breakdown of Risk Factors

• *Both Sexes Combined:
  • Cigarette smoking
  • Excess body weight
  • Alcohol consumption
  • UV radiation
  • Physical inactivity
  • Other factors: HPV infections, low fruit/vegetable intake, processed meat, low dietary fiber, H. pylori infection, red meat, secondhand smoke

Specific Risk Factor Impact

• *Men:
  • Higher prevalence with cigarette smoking
  • UV radiation
  • Alcohol consumption
  • Low fruit/vegetable intake
• *Women:
  • Cigarette smoking
  • Excess body weight
  • Alcohol consumption
  • Physical inactivity
  • UV radiation
  • HPV infection

Cancer Preventability

• Certain cancers are nearly 100% preventable through risk factor management:
  • Cervical cancer (HPV vaccination reduces incidence by 95-100%)
  • Kaposi's sarcoma (requires HIV and herpesvirus 8 infections)
  • Anal cancer, melanoma, larynx, bronchus, trachea, esophagus, and oral cavity cancers

Lung Cancer Screening

• Significance: Late-stage lung cancers are often detected after metastasis, reducing cure rates.
• Recommendation: Annual low-dose CT scans for early detection and prevention.
  • Specifically for ages 50-80 with a 20 pack-year history who currently smoke or quit within the last 15 years.

Detection Techniques

• Chest X-ray: Good for gross findings but not for small tumors.
• Low-dose CT Scan: More effective in detecting small nodules, involves less radiation.

Screening Criteria

• United States Preventive Services Task Force: Grade B recommendation
  • Ages 50-80
  • 20 pack-year smoking history
  • Current smokers or those who quit within the last 15 years
  • Capable of undergoing surgery

Conclusion

• Action Steps:
  • Evaluate patients' smoking history and age for screening eligibility.
  • Annual screens until age 80 or 15 years post-quitting.
  • Discuss risks and benefits with patients.

Further Learning

• Resources Available: Educational videos and resources on lung cancer, COPD, and related health conditions at medcram.com
• Subscription: Encourage subscriptions for continued medical education.