BackgroundThe incidence of neoplasms of the appendix is low and accounts for 1% of all cancers. It is often an incidental finding, detected in 0.2 -0.3% of all appendicectomy specimens. PurposeWe studied the incidence of primary lesions of the appendix in a cohort of patients who underwent appendicectomy as part of cytoreductive surgery for gynaecological malignancies. Methods A total of 182 cases were identified from the database of the Department of Histopathology over the course of 6 years (2015-2020). The histopathology reports for these cases were reviewed, and data including patient age, primary gynaecological cancer type, macroscopic abnormality in appendix, presence of a primary lesion of the appendix and its type was collated. ResultsThe median age of the entire cohort was 54 years (range 17-83 years). An appendiceal lesion was identified in 12/182 cases (0.5%), whose median age was 61years (range 48-77 years). The appendiceal pathology included low grade appendiceal neoplasm in 4/12 (33%), well differentiated (grade 1) neuroendocrine tumour in 2/12 (17%), sessile serrated lesion with no dysplasia in 4/12 (33%) and hyperplastic polyp in 2/12 (17%) cases. There was no association with any particular gynaecological cancer type with the presence of appendiceal lesions. A macroscopic abnormality in the form of dilatation of appendix was noted in one of the 12 cases (8%). A tumour nodule was identified grossly in another case whilst metastatic tumour deposits were confirmed microscopically in 4/12 cases (33%). ConclusionAppendicectomy in the course of cytoreductive surgery provides an opportunity to identify occult primary appendiceal lesions, particularly in patients over the age of 45. Appendiceal lesions are most often an incidental finding and given the poor correlation between gross appearance of the appendix and microscopic findings in the majority of these lesions, the entire appendix should be submitted for histological assessment.