Self-report. Basal cell carcinoma is the most common form of skin cancer, and it is more common. In Sweden, basal cell carcinomas are subdivided based on pathological tissue growth method and clinical presentation into low, medium and highly aggressive subgroups. High-risk tumors (moderate to very aggressive basal cell carcinomas in the head and neck region) can cause significant morbidity due to destructive localized growths.
Several studies show that up to 40-50 percent of high-risk tumors are removed non-radically during conventional surgical excision. Mohs surgery is a frequent surgical technique to remove skin tumors in rounds with intraoperative microscopic root control in cryosurgery incisions. This method is superior to achieving the radicalization of high-risk basal cell carcinoma. In Mohs surgery, 100 percent of the tissue resection surface is examined, compared to approximately 1 percent in normal incisions. The method also allows for the smallest possible margins of surgical removal and preservation of the largest possible amount of healthy skin. Due to insufficient resources, only about 350 operations with Mohs surgery are performed each year in three Swedish cities (Gothenburg, Lund and Stockholm), despite the fact that about 3000 cases of high-risk basal cell carcinoma of the head and neck area are diagnosed annually.
A recently published retrospective study analyzed all patients who underwent Mohs surgery for basal cell carcinoma in the Department of Dermatology, University Hospital Sahlgrenska in Gothenburg, between 2012 and 2019 . We included 903 basal cell carcinomas in 813 patients (70.1 percent primary tumors, 10.4 percent non-radical and 19.5 percent recurring). The mean number of rounds of Mohs surgery was significantly lower for primary basal cell carcinoma compared to recurrence (P = 0.03), and the mean final defect size at extremes was significantly lower with primary basal cell carcinomas compared with both recurrent types (P <0.0001 Radically resected neoplasms (P = 0.003). Primary basal cell carcinoma tends to be remodeled frequently with primary closure (P = 0.08). Of all recurrences, 77.8 percent had been treated one way before, 27.2 percent had two different methods before, and 1.1 percent had three different treatment modalities before Mohs surgery. Non-radically resected tumors underwent unsuccessful surgical resection 1.5 times (1-6 times) prior to Mohs surgery.
Performing Mohs surgery more often in primary basal cell carcinoma rather than as a salvage method allows for a better use of resources and results in less patient suffering. To reduce the number of failed treatments, all physicians treating patients with basal cell carcinoma should have a good knowledge of treatment indications.  And benefits of Mohs surgery.