BACKGROUND:: Local recurrence is a significant risk after anal squamous cell carcinoma. OBJECTIVES:: Occurrence of high-grade squamous intraepithelial lesions and local recurrence after anal cancer at surveillance with high resolution anoscopy. DESIGN:: Retrospective observational study. SETTING:: Anogenital neoplasia referral center. PATIENTS:: There were 76 anal/perianal cancers from 1998-2018, 63 eligible patients, 3 excluded, total 60 patients, 35/60 (58%) male. INTERVENTION:: High resolution anoscopy after chemoradiation, or excision only for anal squamous cell carcinoma. MAIN OUTCOME MEASURES:: Primary local recurrence and high-grade squamous intraepithelial lesion detection rate. RESULTS:: Sixty patients, 27% HIV positive, underwent surveillance over median 42 (range 7-240) months’ follow-up. Seven had had a prior local recurrence at study entry so were analyzed separately. Thirty of 53 underwent chemoradiation (57%) and 23/53 excision alone (43%). 33 were perianal, 20 anal canal. Ten of 30 of chemoradiation group had been Stage 1 (33%) compared to 22/23 of the excision group (96%, p<0.001). OUTCOMES:: High-grade squamous intraepithelial lesions were detected in 4/30 (13%) after chemoradiation, and in 17/23 (74%) after excision only (p<0.001). 20/21 (95%) high-grade lesions were treated with ablation. Six of seven (86%) with prior local recurrence had high-grade squamous intraepithelial lesions over median 21 months’ follow-up. One local recurrence (T1N0M0) occurred during surveillance after primary chemoradiation (0.56/1000 person-months), none after excision only and 2/7 with prior local recurrence developed further local recurrence (6.86/1000 person-months). All 3 local recurrences occurred after treatment of high-grade squamous intraepithelial lesions. There were no metastases, abdominoperineal excisions or deaths from anal squamous cell carcinoma. LIMITATIONS:: Retrospective data. CONCLUSIONS:: High-grade squamous intraepithelial lesions after anal squamous cell carcinoma is more common after excision only than after chemoradiation. Local recurrence is low in this high resolution anoscopy surveillance group in which high-grade squamous intraepithelial disease was ablated. Excision of small perianal cancers appears safe; however, a subset of patients is at excess risk. See Video Abstract at http://links.lww.com/DCR/B285.