Epidemiology of cancer in Khyber Pakhtunkhwa (KP), Pakistan, 2020-2023: a retrospective, province-wide, multicentre observational study.

Abstract

The province of Khyber Pakhtunkhwa (KP), located in the northwestern region, is the third most populous province in Pakistan, with a population estimated at 41 million. To determine the cancer counts and age-standardised incidence rates (ASIRs) per 100 000 population over a 4-year period for KP, 2020-2023, and to compare them with those available for two districts of Pakistan and nearby areas. A retrospective, province-wide, multicentre observational study. Shaukat Khanum Memorial Cancer Hospital and Research Centre in Lahore, as the collaborating centre, with data reported from leading cancer treatment and diagnostic facilities across the country entered into its hospital information system. New cancer cases diagnosed from 2020 to 2023 among inhabitants of KP. Primary measures were cancer counts, proportions and ASIRs per 100 000 population for children (0-14 years), adolescents/young adults (15-19) and adults (≥20 years) in KP. Secondary analyses compared ASIRs across regions. A total of 57 852 malignancies were recorded in KP over a 4-year period: 51.6% in females and 48.4% in males. The ASIR per 100 000 persons was as follows: in pre-adolescent girls, 4.2; in pre-adolescent boys, 6.6; in adolescent females, 7.9; in adolescent males, 9.7; in adult females, 103.5; and in adult males, 90.1. Overall, breast cancer accounted for the highest proportion of cases (16.3%). In children, leukaemia had the highest ASIR in KP (1.9 in males, 1.0 in females) and in Lahore (3.3 in males, 2.1 in females), whereas in Karachi, the ASIR was high for bone tumours (8.6 in males and 5.6 in females). In adolescents, the ASIRs for leukaemia (0.8-2.0) were high in all three regions, as were those for ovarian cancer (0.8) in KP. In adults, the ASIRs for breast cancer among females were high in KP (32.6) and Lahore (76.7) but very high in Karachi (177.8). In adult males, the ASIR for prostate cancer was 9.1 in KP and 10.7 in Lahore, while in Karachi, it was 26.0 for colorectal/anal cancer. Overall, breast cancer had the highest ASIR in KP, Kabul in Afghanistan, and Iran among females, but in males, it was bladder cancer and non-Hodgkin lymphoma (NHL) in KP, and in Kabul and Iran, stomach cancer. In KP, among children and young adults, haematologic malignancies; in adolescents, bone tumours and ovarian cancers; and in adults, breast and prostate cancers were frequently documented. There were similarities among the three regions (KP, Lahore and Karachi) in incidence rates. Differences were noted in the top three cancers among males in KP versus Kabul and Iran. This report lays the foundation for future comparative analyses and can guide the development of infrastructure for cancer prevention, diagnosis, and management within the province of KP.