Clinical and histological findings in re-excision of incompletely excised cutaneous squamous cell carcinoma

SummaryBackgroundCurrent guidelines mandate treatment of primary cutaneous squamous cell carcinoma (SCC) through to completion, including the demonstration of a margin of normal tissue, with surgical excision as the treatment of choice. Histologically incomplete excisions of all cutaneous SCC are preferably treated by surgical re-excision. The yield of performing further resection of scar tissue in patients with incompletely excised SCCs has not been previously evaluated.MethodsA retrospective audit was conducted of 676 consecutive patients with surgically managed SCCs treated in our unit during 2005–2006.ResultsOne hundred and nineteen (17.6%) tumours were incompletely excised, of which 84 underwent further excision. Routine histological examination revealed residual SCC in 24 (28.6%) of these specimens. Logistic regression analysis revealed tumour diameter and Breslow thickness to contribute independently to residual SCC (P < 0.001). A lengthier delay between initial excision and re-excision predicted less residual tumour (P < 0.005). Although the positive re-excision group tended towards a higher mean age (79 ± 9 vs 74 ± 12), with more head and neck lesions (79 vs 66%), logistic regression revealed no independent influence of age, gender, histological grade or anatomical site of the original lesion.ConclusionIn our series, 28.6% of incompletely excised primary cutaneous SCCs showed residual tumour in re-excision specimens. Factors associated with residual tumour were similar to characteristics of high risk SCCs; larger lesions in particular are more likely to result in residual SCC at re-excision and may benefit from greater excision margins at the time of original resection. It is possible that regression of remaining tumour cells may contribute to our time-dependent findings and this warrants further research.