Incomplete excision of basal cell carcinoma and its associated risk factors

Basal cell carcinoma (BCC) is the most common type of skin tumor. Surgical removal has remained the gold standard of treatment for BCC, but incomplete removal is an important clinical challenge. The goal of our study was to evaluate the incomplete excision of BCC and the factors affecting it.
In this retrospective study, 361 histological samples of BCC excisions referred to the Pathology Department of Imam Reza Hospital, Mashhad, Iran, from 2004 to 2018 were reviewed. Data including age, gender, tumor site, size, histopathologic subtype, surgical margin involvement, and the surgeon’s specialty were recorded.
The incomplete removal rate was 20%. Ten percent of the lesions had deep margin involvement, 5.8% had lateral margin involvement, and both margins were involved in 4.2% of cases. Incomplete excision had a significant relationship with the following variables: nodular, mixed, and sclerosing types; the 60-70 years age group; lesions larger than 2 cm, location in nose and canthi; and excision by an otorhinolaryngologist, ophthalmologist, or dermatologist.
In this study, the frequency of incomplete excision was relatively high compared with other studies. Therefore, it is suggested to perform a diagnostic biopsy before the complete excision of BCC. Excision with a wider margin or using Mohs surgery is recommended for midface lesions, older individuals, nodular, mixed, or sclerosing lesions, and for tumors larger than 2 cm.