Table 2. Included studies on Mohs micrographic surgery for SCC and BCC.

MMS: Mohs micrographic surgery; KC: BCC: basal cell carcinoma; SCC: squamous cell carcinomas; KC: keratinocyte carcinoma

Authors and reference	Size of the study	Treatment details	Results	Conclusion
Weesie et al. 2019, [17]	549 patients	Patients with periocular KCs treated with MMS in a tertiary MMS referral hospital.	Out of a total of 729 periocular skin cancers, 683 (93.7%) of them were BCCs and 46 (6.3%) were SCCs treated with MMS. Among them, 549 were primary tumors and most of them were located in the medial canthus or lower eyelid (649, 89.0%).	MMS is an excellent treatment option for keratocystic odontogenic tumors located around the eyes (periocular region), as it has a low rate of recurrence. Given the sensitive anatomical location, an interdisciplinary approach involving multiple healthcare professionals should be strongly considered for the management of these cases.
Jiménez et al. 2018, [18]	2,669 patients	BCC and SCC patients who underwent MMS	Of these, 2,448 patients (93%) were diagnosed with BCC and 181 patients (7%) were diagnosed with SCC. Patients with SCC were generally older than those with BCC, with a median age of 73 years compared to 68 years for the BCC group. Patients with SCC also presented with immunosuppression more frequently. The tumor size was significantly larger in the SCC group compared to the BCC group. Additionally, deeper invasion was more common in SCC, resulting in larger defects after surgery.	Significant differences exist when comparing MMS outcomes for BCC and SCC. Understanding these differences can help healthcare providers better prepare patients and plan the surgical approach, thereby optimizing treatment outcomes.
Silapunt et al. 2006, [19]	A total of 117 patients with 144 invasive SCCs	Patients with invasive SCCs of the auricle following MMS	The most common site for the occurrence of tumors was the helix, accounting for 50.7% of cases. A total of 122 tumors were identified, including five recurrent tumors from four patients. These patients underwent MMS and did not experience further recurrences. Follow-up time for 35 tumors was less than two years, while for 87 tumors, it was two years or more. Based on chart reviews and telephone contacts, the two-year local recurrence rate following MMS was found to be 5.7% (five out of 87 tumors) and the average size of these tumors was 3.5 cm2.	Previously, invasive SCC of the ear used to be a challenging condition with a poor outlook. However, with timely detection and MMS treatment, the prognosis of this disease has significantly improved.
Chagas et al. 2012, [20]	79 patients	Patients undergoing MMS and study issues related to the number of surgical stages	Skin types II and III were the most commonly encountered, representing 41% and 36.1% of cases, respectively. BCC was the predominant tumor type, accounting for 89.1% of cases, with the solid subtype being the most prevalent at 44.6%, followed by the sclerodermiform histological subtype at 32%. The nasal region was the most frequent site for these tumors, at 44.6%. A significant majority of the operated tumors were recurrent lesions, with 72.7% falling into this category.	Recurrent tumors and those larger than 2 cm required multiple surgical stages for removal, although there was no statistically significant difference (p=0.12 and 0.44, respectively).
Paoli et al. 2011, [21]	587 patients	Aggressive and/or recurrent facial BCC treated with MMS	The five-year recurrence rates determined through Kaplan-Meier survival analysis were 2.1% for primary tumors that were previously untreated, 5.2% for recurrent BCCs, and 3.3% overall. A total of 87.9% of the tumors necessitated at least two rounds of MMS. On average, the size of the surgical defect following complete excision was roughly double the size of the defect after removing the clinically visible tumor with a 2-3 mm margin.	Despite being the preferred treatment for aggressive and recurrent facial basal cell carcinomas, MMS is not widely utilized in Scandinavia.
Galimberti et al. 2010, [22]	2412 patients	2412 basal cell carcinomas treated with MMS	50.5% of the patients were female, while 49.5% were male. The average age of the patients was 70.7 years, ranging from 8 to 100 years. The tumor's histologic type was solid in 65.3% of cases, and in 89% of cases, the tumor was located on the head or neck. Ten percent of the tumors recurred after previous treatment.	MMS is effective for the treatment of high-risk basal cell carcinoma.
Català et al. 2013, [23]	534 patients	Patients who underwent 534 consecutive MMS procedures for confirmed BCCs were studied, with the primary focus on detecting biopsy-confirmed recurrence of BCC at the original anatomical site following MMS.	The nasal/perinasal region was the most common location for the 534 consecutive MMS interventions, accounting for 38.4% (n=205) of the cases. Nearly half (47.9%, n=256) of the surgical procedures were for primary BCCs while the remaining 52.1% (n = 278) were for recurrent or residual BCCs. The raw recurrence rate following MMS was 1.2% (3/256) for primary BCCs, compared to a significantly higher rate of 10.4% (32/278) for recurrent BCCs.	MMS is a highly effective treatment for primary high-risk BCCs. However, the cumulative probability of recurrence increases significantly when tumors with prior recurrences are referred for MMS.