Reappraisal of giant basal cell carcinoma: Clinical features and outcomes

Background: Giant basal cell carcinoma (GBCC) is a rare subgroup of basal cell carcinomas with a diameter of >5 cm. Current evidence about determining factors is conflicting, suggesting patient neglect, on the one hand, and biologically aggressive behaviour, on the other, with outcomes varying from clearance to death. We aimed to clarify the natural history of GBCC and its response to treatment. Methods: We extracted information from clinical records of all patients with GBCC treated from 1998 to 2017 in a tertiary oncology hospital in northwest England. Associations between patient and tumour characteristics were investigated, and modes of treatment and outcomes were assessed. Results: In the 20-year study period, 43 patients (median age 76 years; 23 (53%) female), 3 of whom had Gorlin syndrome, were treated for GBCCs. Median diameter was 6.3 cm, and median time to presentation was 5 years. Seven (16%) GBCCs arose from recurrent BCC, while the majority (84%) presented de novo. The size of GBCC was significantly correlated with delay in presentation (p = 0.03) but not with age or sex. Of 41 patients receiving definitive treatment, 19 GBCCs were treated by excision with ≤1 cm margin and none recurred during follow-up, compared with 10 recurrences of 23 treated with photodynamic therapy (PDT), and 1 of 7 recurred after radiotherapy. Two of 43 patients with GBCC (<5%) presented with extensive local invasion, one of whom also had distant metastases, and both died of the disease. Conclusion: The majority of GBCCs are not clinically aggressive and respond to conservative surgical treatment with a low risk of recurrence.