Radiation therapy: a major factor in the five-year survival analysis of women with breast cancer in Lagos, Nigeria.

Purpose: This retrospective study was carried out to examine five-year survival from breast cancer cases diagnosed between 2005 and May 2008 in Nigerian women.

Material And Methods: Two hundred and twenty-four patients were entered into the study. Five-year survival was evaluated using proportional hazard model proposed by Cox to assess variables such as age of diagnosis, menopausal status, and stage of the disease in the two treatment groups: surgery/chemotherapy or surgery/chemotherapy/radiotherapy.

Results: Findings revealed that the different staging of disease and treatment are independent predictors of disease outcome whereas age of diagnosis and menopausal status although associated with low hazards, are not significant. TNM Stage I (Hazard Ratio=0.153, 95% CI 0.45-0.51, P=0.003), II (Hazard Ratio=0.245, 95% CI 0.12-0.46, P=0.0001), and III (Hazard Ratio=0.449, 95% CI 0.31-0.46, P=0.0001) showed significantly greater survival rates compared to TNM Stage IV for patients receiving surgery/chemotherapy. Similarly, for patients receiving surgery/chemotherapy/radiotherapy TNM Stage II (Hazard Ratio=0.110, 95% CI 0.02-0.46, P=0.003) and III (Hazard Ratio=0.238, 95% CI 0.07-0.73, P=0.012) also showed significantly greater survival rates compared to TNM Stage IV. Treatment had a significant impact on survival independent of stage, age, and menopausal status. Patients receiving surgery/chemotherapy/radiotherapy had a significant increase in survival outcome for TNM Stage (II, P=0.045; III, P=0.0001); age groups (40-49, P=0.021; 50-59, P=0.016; 60-69, P=0.017; >70, P=0.025); and menopausal status (premenopausal, P=0.049; postmenopausal, P=0.0001) compared to those receiving surgery/chemotherapy.

Conclusion: The five-year breast cancer survival rate in Lagos, Nigeria 24.1% (54/224) is relatively poor compared to most countries in the world and needs to be improved. Poor survival rates are mainly attributed to late presentation and poor follow-up, hence early detection through breast cancer awareness programs, appropriate logistics and better management of patients through guidelines for the treatment of breast need to be implemented to improve survival.