Incidental secondary findings in hemorrhoidectomy specimens: a 16-year experience from a single academic center

Hemorrhoidectomy specimens serve as an excellent resource for study of incidental anal pathology. Detection of most incidental findings is quite rare, although diagnosing clinically significant lesions can have profound impact on the clinical follow-ups. While there are many case reports of incidental findings in hemorrhoidectomy specimens, there are few large studies focused on this topic. The aim of this study was to describe the spectrum and likelihood of detecting incidental findings in hemorrhoidectomy specimens. We reviewed all hemorrhoidectomy specimens that showed incidental clinically significant diagnoses over a 16-year period (2003-2019) for this study. Patient's age, sex, and significant clinical history (Human Immunodeficiency Virus (HIV) status, precursor lesions, other malignancy) were recorded from clinical notes. We identified incidental clinically significant findings in 72 of 1612 (4.5%) specimens. We identified 7 incidental malignancies (squamous cell carcinoma, verrucous carcinoma, adenocarcinoma, mixed adenocarcinoma and neuroendocrine carcinoma, poorly differentiated neuroendocrine carcinoma, melanoma), 54 anal intraepithelial neoplasias (AINs), and 11 benign findings (melanocytic lesions, colorectal polyps, angiokeratoma, infectious/inflammatory). Within the AIN group, the detection of low-grade squamous intraepithelial lesions (LSILs) remained steady; there was a recent, sustained rise in detection of high-grade squamous intraepithelial lesions (HSILs), with more cases showing HSILs (2.6%) than only LSILs (0.7%). In 72.2% of patients, the incidental secondary finding represented a first diagnosis for that entity in the anal canal. Thirty seven percent of patients with anal dysplasia in the hemorrhoidectomy specimen had a prior diagnosis of squamous dysplasia in the anogenital tract. Overall, significant incidental findings were detected in 4.5% (72/1612) of hemorrhoidectomies, supporting routine histological examination of these specimens.