BACKGROUND
Analysis of hospital records is crucial for understanding cancer trends, identifying epidemiological patterns, guiding clinical strategies, and informing prevention, diagnosis, and treatment policies.

OBJECTIVE
To characterize the site distribution and annual trends of newly diagnosed cancers at a national tertiary institute, by sex and age, from 2018 to 2024.

METHODS
A retrospective observational study used the INCan hospital cancer registry, including all incident cases classified by ICD-10. Counts and proportions were summarized by cancer type, sex, and age. Temporal trends were assessed using linear regression and change-point analysis, estimating annual absolute and percentage changes. Statistical significance was set at p < 0.05 with 95% confidence intervals.

RESULTS
43,870 cancer cases were recorded (annual median: 5,571), 63% in women and 37% in men. Trends revealed significant increases in several cancers, including breast, prostate, endometrial, gastric, and testicular cancers, and a resurgence in non-follicular lymphoma, while lung cancer showed a sustained decrease. Overall, malignant tumors exhibited a significant upward trend (AAPC 8.7%), with the greatest acceleration between 2020 and 2024.
In the total cohort, 79.5% of cases were diagnosed between the ages of 40 and 69, with the highest frequency in the 50–59 age group (22.7%).
Those under 20 years of age represented only 1.7% of diagnoses.
In women, the most frequent primary tumors were breast, cervical, endometrial, ovarian, and thyroid cancers.
In men, the most frequent primary tumors were prostate, testicular, kidney, lung, and non-Hodgkin lymphoma.
Marked differences were observed in the distribution of primary tumors by sex.

CONCLUSION
The post-2020 increase indicates shifts in the epidemiological landscape, reflecting both a real rise in disease burden and recovery of diagnostic capacity after the pandemic. These findings underscore the need to strengthen cancer surveillance, prevention programs, and oncology service planning in Mexico.

Cancer incidence trends and distribution by site, age group, and sex (INCan, 2018–2024).