Ten-year pathology-based cancer registry at a tertiary referral hospital in Kenya (2015–2024): distribution of cancers and completeness of pathology reporting

Population-based cancer registries remain limited in low- and middle-income countries (LMICs). In Kenya, their coverage is below the 20% threshold recommended by the International Agency for Research on Cancer. Pathology-based registries can provide complementary data in such contexts. This study describes the distribution of cancers diagnosed at a tertiary referral hospital in Nairobi over ten years, and evaluates the completeness of pathology reporting for selected cancers using College of American Pathologists (CAP) protocols. We conducted a retrospective review of all histologically confirmed cancers at the Aga Khan University Hospital, Nairobi, from 2015 to 2024. Data were extracted from the institutional database. The data included region of origin, demographics, cancer site, and histologic diagnosis. Completeness of reporting was assessed in stratified random samples of breast and colorectal cancer reports against the College of American Pathologists (CAP) cancer reporting protocols. A total of 32,445 cancer cases were diagnosed over the study period, including 18,899 females and 13,546 males (58.3% and 41.7%, respectively). The median age at diagnosis was 52 years (Interquartile range 41–64) in females and 61 years (Interquartile range 47–71) in males, with an overall median age of 56 years (Interquartile range 43–68). Most cases occurred in the decades between 51 and 60 years (6,816/32,445) and 61–70 years (6,556/32,445). Overall, breast cancer was the most frequent malignancy (7,236/32,445; 22.3%), followed by esophageal (3,839/32,445; 11.8%) and prostate cancer (3,023/32,445; 9.3%). Among women, breast (6,926/18,899; 36.6%), cervical (2,230/18,899; 11.8%), and esophageal cancers (1,610/18,899; 8.5%) predominated, while among men, prostate (3,023/13,546; 22.3%), esophageal (2,229/13,546; 16.5%), and non-Hodgkin lymphoma (957/13,546; 7.1%) were most common. Pediatric cancers (≤ 19 years) accounted for 1,325 cases (4.1%). Completeness of pathology reporting exceeded 95% for most required elements, and it improved from 83.3% in 2015 to over 98% in 2024. This large pathology-based dataset highlights the cancer burden in Kenya, with breast and prostate cancers predominating among females and males, respectively. There are regional disparities in sources of referral for certain cancer types. Pediatric malignancies represented a small proportion of cases. Pathology reporting for key data elements was generally of high completeness.