Background/Objectives: Cancer poses a significant global health threat. Real-world data, such as Electronic Health Records, offer timely insights into cancer outcomes, including the identification of potential prodromes. This study characterizes patients with 34 types of incident cancers using data from a primary care real-world database from Catalonia, Spain.

Methods: We performed a population-based descriptive epidemiological study using routinely collected data from SIDIAP database, a primary care electronic health records database representative of the Catalan population. Data was used from individuals with at least one year of prior history and a cancer diagnosis of one of the 34 cancer types. Cancer definitions were based on those used in GLOBOCAN 2020 database. The study period spanned from 1^st January 2006 until database exit, death or study end date on 30^th June 2023. We described patient characteristics, including demographics and the prevalence of clinical factors prior to diagnosis.

Results: Non-melanoma skin, colorectal, breast, prostate, lung, and bladder cancers were the most common cancers, each affecting over 50,000 individuals. Vaginal and nasopharyngeal cancer were the least common, with less than 1,000 individuals. The prevalence of non-sex-specific cancers was higher in males, especially bladder and respiratory cancers (oesophagus, hypopharynx, larynx, lung, nasopharynx, and oropharynx) for which over 70% of cases occurred in males. Additionally, individuals diagnosed with bladder and respiratory cancers exhibited a higher percentage of former smokers (over 40%) compared to the other cancers. Individuals under 60 years were more commonly diagnosed with Hodgkin lymphoma, thyroid, cervix, nasopharynx, Kaposi sarcoma, and breast cancers, while individuals over 70 years were more frequently diagnosed with colorectal, stomach, vulva, pancreatic, non-melanoma skin cancer, mesothelioma, multiple myeloma, prostate, and gallbladder cancers. Obesity was most prevalent in individuals with corpus uteri cancer, gallbladder cancer, and cancers of the vagina and vulva. Hypertension was the most common pre-diagnosis condition overall, while COPD was most prevalent in respiratory cancers, HIV in Kaposi sarcoma patients, and type 2 diabetes among gallbladder, kidney, liver, lung, mesothelioma, penis, stomach, and especially pancreatic cancer patients.

Conclusions/Recommendations: This study offers a comprehensive demographic and clinical description of patients with 35 different cancer types in Catalonia, serving as a valuable resource for future research and healthcare planning.