Examining the Completeness of Breast Cancer Pathology Reports Registered in the Population-Based Cancer Registration System in Iran during 2016 to 2018.

Background: Ensuring the comprehensive and accurate representation of data within cancer registries holds paramount significance across various facets of public health decision-making. This study delves into the evaluation of data completeness in breast cancer (BC) pathology reports within a population-based cancer registration system in Iran, spanning the period from 2016 to 2018.

Methods: Employing a retrospective and descriptive analytical approach, we harnessed secondary data extracted from pathology reports encompassing breast cancer diagnoses, which were duly recorded in the Integrated Cancer Information Management System database during 2016-2018. A total of 4000 pathology reports were thoughtfully selected from each of the three years. The spectrum of pathology information encompassed tumor type, site grade, size (T), and involvement of lymph nodes (N). Summary statistics were provided as percentages of categorical variables and mean with standard deviation of continuous variables. A comparison of categorical variables was performed using the Chi-squared test.

Results: The participants' mean age was 51.8±12.5 years. Among the 12,000 studied patients, 5744 (47.9%) were ≤ 50 years old, 5233 (43.6%) were aged 50-69 years, and 1023 (8.5%) were >60 years old. The completeness of BC pathology reports varied for different variables. Interestingly, the completeness of these variables increased with older age groups. The proportion of specific tumor types differed significantly among age groups (P = 0.001). Notably, the prevalence of invasive ductal carcinoma was higher in the ≤ 50 years age group compared to the older cohorts. Likewise, notable variations in tumor sizes were observed (P = 0.009), with a higher prevalence of missing tumor size data noted in the age group ≤ 50 years. On the other hand, pathologic T stage also demonstrated age-dependent variations (P = 0.014), indicating a higher prevalence of missing stages in the ≤ 50 years age group. Finally, tumor grade exhibited a statistically significant difference (P < 0.001), with a higher proportion of grade 1 tumors observed in the 50-69 years age group.

Conclusion: Tumor grade had the highest completeness rate, while tumor size, pathologic T stage, and pathologic N stage had the lowest. Therefore, a good understanding of completeness of pathology reports, as well as improvement in the registration of stage, integrated system at the national level for BC is warranted.