Epidemiologic aspects of breast cancer incidence in Baku

Aim. Study of incidence and mortality from breast cancer in different administrative territorial districts of Baku in 2016.

Methods. Statistical report forms №7 were used (reports on malignant neoplasms of the Ministry of Healthcare of Azerbaijan Republic) as well as the database of cancer registry of the National center of oncology of Baku in 2016. Primary incidence index (per 100 000), standardized incidence ratio (per 100 000), prevalence rate (per 100 000), extensive index (% compared to other types of oncologic pathology revealed in Baku in 2016), lethal index (%), crude mortality rate (per 1000), aggressiveness index were calculated.

Results. In the structure of malignant neoplasms in Baku among females, breast cancer takes the first place (extensive index 31.6%). 7.4-fold variation of breast cancer morbidity in different administrative districts was observed (p <0.05) - from 142.4 per 100 000 in Yasamal raion of Baku to 19.1 per 100 000 in Qaradag raion (p <0.05). Variation of prevalence rate was less prominent (3.1 times, p <0.05): from 655.8 per 100 000 in Sabail raion to 209.4 per 100 000 in Binagadin raion. Crude mortality rate was similar in all districts and varied from 0.1 to 0.5 per 1000. More than 30-fold variation of lethal index was observed with the average index in Baku of 17.3%. The more distantly from the center of the city the district is located, the higher the lethal index was (p <0.05). One of the main parameters determining neoplasm prognosis was extension of tumor at the moment of its diagnosis. Among primary patients, those with clinical stages I-II prevailed (59.3%), the proportion of patients with stage III was 22.0%, stage IV - 18.7%. Agressiveness index varied from 0.1 (in Pirallahi raion) to 0.5 (in Binagadin and Sabail raions), the total city index was 0.4. With the growing age, increasing standardized incidence ratio was observed, and its peak value was in the age group 50-59 years (14.5 per 100 000). Generally, in Baku breast cancer incidence among females regardless of their age was 47.7 per 100 000, and it was significantly higher in Baku than generally in the republic (35.0 per 100 000, p <0.001).

Conclusion. The first place in the structure of oncology diseases among female citizens of Baku is taken by breast cancer (31.6%), women aged 50-70 years have the highest risk of the disease; the highest lethal index was reported for females with breast cancer living in the most distant districts of Baku that indicates the necessity for improved preventive activity in those districts.