DS03 Surgical excision may not be necessary for biopsy-confirmed cutaneous squamous cell carcinoma with a clinically resolved biopsy site

Abstract

Current treatment of cutaneous squamous cell carcinoma (cSCC) mostly involves surgical excision, with few studies examining tumours managed by watchful waiting when the lesion resolves following biopsy or curettage and cautery. We aimed to describe oncological outcomes for patients diagnosed with biopsy-proven cSCC that clinically resolved at follow-up and was subsequently managed conservatively. This was a single-centre, retrospective cohort study including patients with histopathologically confirmed SCCs, with no residual tumour clinically apparent, managed by a watchful waiting approach over a 3-year period (September 2022 to September 2025) in South East England. In total 319 patients had biopsy-proven invasive SCCs (as opposed to direct for surgical excision). The most common site was head and neck (71%). The patients had a mean age of 81 years, and two-thirds were male. The majority of the lesions were well (17%) to moderately (50%) differentiated. In total, 68 (21%) were managed with watchful waiting and the majority (94%) had specialist skin cancer nurse follow-up with no recurrence. The remaining patients either died from unrelated causes (5%) or were lost to follow-up (1%). Overall, 46 of 68 (68%) had curative-intent curettage and cautery, while the remaining 22 (32%) had diagnostic biopsies. Of these, 59% (n = 13) were punch and 41% (n = 9) were curette. In total, 251 (79%) patients had further surgical excision, one-third of which were high risk based on the BAD criteria. Only 46% had residual tumour in the surgical specimen, with the others containing scar tissue or actinic keratoses. In this cohort, only 1% of cases (n = 3) recurred, with one having involved margins on re-excision and requiring adjuvant radiotherapy. These local recurrence rates compare very favourably with reported recurrence for surgically managed SCCs. We propose a watchful waiting approach for the management of clinically resolved, low-risk lesions in appropriate cases, thus reducing unnecessary patient morbidity and utilizing resources more efficiently.