A review of the evidence for Mohs micrographic surgery. Part 2: basal cell carcinoma.

Mohs micrographic surgery (MMS) is considered the gold-standard treatment for basal cell carcinoma (BCC) particularly for sites with a high-risk of incomplete excision such as the central face, for tumours with an aggressive growth pattern and consequent unpredictable subclinical extension and for recurrent tumours. However, the process is more time-consuming than for standard excision (SE), and the magnitude of benefit is uncertain. This article aims to provide a more complete picture of current evidence, including a review of cosmetic outcomes, tissue-sparing ability and cost-effectiveness of MMS. Although robust evidence is lacking, there is a large volume of observational data supporting a low recurrence rate after MMS. The risk of incomplete excision and higher recurrence rate of standard excision favours the use of MMS at high-risk sites. There is some low-certainty evidence that MMS results in a smaller defect size compared with SE, and that incomplete excision with SE results in larger defects. Larger defects may affect cosmetic outcome but there is no direct evidence that MMS improves cosmetic outcome compared with SE. There is conflicting evidence regarding the cost of MMS compared with SE, as some studies consider MMS less expensive than SE and others consider it more expensive, which may reflect the healthcare setting. A multicentre 10-year randomized controlled trial comparing MMS and SE in the treatment of high-risk BCC would be desirable, but is unlikely to be feasible or ethical. Collection of robust registry data capturing both MMS and SE outcomes would provide additional long-term outcomes.

A multinational survey characterizing the use of surgical magnifying loupes in dermatological surgery.

BACKGROUND: The use of surgical loupes has not been well-documented in dermatological surgery. OBJECTIVES: An online questionnaire was developed to characterize the use of loupes in dermatological surgery. METHODS: The questionnaire was circulated to the memberships of the British Society of Dermatological Surgery, the European Society of Micrographic Surgery, and the Australasian College of Dermatologists. Responses were analyzed with a mixed methods approach using quantitative data analysis and inductive content analysis. RESULTS: One-hundred twenty-five valid responses were received from 20 nations. Most respondents were from England (40%; 50/125), Australia (16%; 20/125), and the Netherlands (14.4%; 18/125). Overall, 71.2% (89/125) of respondents were consultants/Facharzt/attending. Furthermore, 55.2% (69/125) of respondents were Mohs surgeons. In dermatological surgery 38.4% (48/125) of respondents used surgical loupes routinely. The mode magnification level for loupes was 2.5× (67.5%; 27/40), with 3× second place (12.5%; 5/40). Exactly half (20/40) used through-the-lens style loupes and 40% (16/40) used flip-up-loupes. Inductive content analysis of the 51 free-text responses from nonloupe users uncovered several deterring factor themes, including expense (18/51), can manage without/don't need (14/51), and narrow field of view a(11/51), and uncomfortable/too heavy (9/51). CONCLUSIONS: This is the first time the use of surgical loupes in dermatological surgery has been internationally characterized.

A review of Mohs micrographic surgery for skin cancer. Part 3: Squamous cell carcinoma.

This review presents and discusses the evidence for MMS to treat cutaneous squamous cell carcinoma (cSCC). The MEDLINE, Embase and Cochrane databases were searched; 39 papers were identified for recurrence and 2 papers for cost-effectiveness. We included all clinical trials and observational studies, including retrospective reports, and excluded editorials and systematic reviews or meta-analyses. We categorized the evidence under the following headings: tumour recurrence, specific site outcomes (ear, lip, scalp and periocular), cSCC with perineural invasion, and cost-effectiveness. Although there are many observational studies indicating the potential benefits of MMS in the management of certain cSCCs, no randomized controlled trials (RCT) were identified. The evidence from comparitor studies suggests that MMS has a lower recurrence rate than that of other treatments for cSCC, including standard excision. Many studies identified were single-armed, but did demonstrate a low to very low recurrence rate of cSCC following MMS. A single recent study suggests MMS for intermediate cSCC is highly cost-effective compared with wide local excision when all-in costs are considered. Since the overall quality of included studies was mixed and highly heterogeneous, further methodologically robust studies with comparator arms or comprehensive long-term registry data would be valuable. It would be ideal to employ a definitive multicentre RCT but given the evidence to date and multiple advantages to MMS, the lack of clinical equipoise makes this difficult to justify. Comparison with current modalities would likely not be ethical/achievable on a like-for-like basis given MMS provides 100% margin assessment, enables histological clearance prior to reconstruction, and minimizes the removal of uninvolved tissue.

An international survey characterizing Mohs tissue processing techniques and Mohs margin thresholds: how close is too close?

BACKGROUND: From practice, we identified heterogeneity in Mohs micrographic surgery (MMS) specimen tissue processing techniques and specifications, and in the Mohs surgeons' assessment of MMS specimen histological tumour clearance. AIM: By surveying an international cohort of Mohs surgeons, we determined to characterize variation in margin threshold assessment (number of wafers/sections free of tumour to declare tumour clearance). METHODS: An online questionnaire was distributed to Mohs surgeons in the UK, European countries, Australia and New Zealand, assessing the background demographics of the surgeons and the technical factors involved in MMS tissue processing and posing three MMS scenarios to define margin thresholds. RESULTS: In total, 114 consultant/attending-level Mohs surgeons responded, giving a response rate of 33.5% from 20 countries (including UK nations). The first scenario posed was a 20-mm cheek basal cell carcinoma (BCC) excised by MMS with a fully complete first wafer (7 µm) clear of tumour and the second wafer (after trimming interval of 50 µm) demonstrating a small dermal focus of nodular BCC; of the 58 surgeons, 16 (27.6%) would not take another stage. With a follow-up question, 16 of the 58 (27.6%) surgeons specified wanting three clear sections to declare tumour clearance. When the same scenario had a change to a 20-mm infiltrative BCC, 84.2% (48 of 57 surgeons) required a second MMS stage, with a follow-up question clarifying that a third (19 of 57) wanted three clear sections to determine clearance. For a well-differentiated 15-mm squamous cell carcinoma with the same factors there was no majority consensus, with the same proportion of surgeons (22.6%; 12 of 53) calling tumour clearance after one, two and three clear section(s) respectively. For MMS specimen processing specifications, routine sections/wafers of 5-10 µm were reported by 77.4% of respondents (48 of 62) and for trimming interval values, 78.6% (48 of 61) specified a range between 20 and 200 µm. CONCLUSION: By surveying international Mohs surgeons, we highlight surgeon background characteristics, peer-compare assessment of margin thresholds for tumour clearance across three scenarios, and delineate tissue processing and intraoperative approaches.

Evaluation of the Readability of Dermatological Postoperative Patient Information Leaflets Across England.

BACKGROUND: Postoperative patient information leaflets (PILs) provide important guidance to patients after skin surgery. Readability is a method of evaluating information for text comprehension. The recommended level for PIL readability is US grade ≤6. OBJECTIVE: To evaluate the readability of public English dermatological postoperative PILs. MATERIALS AND METHODS: All dermatology departments in England were requested to provide their postoperative PILs. Patient information leaflets were evaluated using Readability Studio (Oleander Software, Vandalia, OH). Two preselected parameters were also noted: whether the PIL was doctor or nurse-written, and whether the PIL was Information Standard hallmarked. RESULTS: Eighty-five of one hundred thirty (65.4%) of PILs were evaluated. Only 29.4% of the PILs were grade level ≤6 with Flesch-Kincaid. The mean readability levels were 7.8 for Flesch-Kincaid, 67 for Flesch reading ease, 10.5 for Simple Measure of Gobbledygook (SMOG), 9.4 for Gunning-Fog, 8 for Fry, and 9.8 for FORCAST. No instruments demonstrated a significant difference between doctor (6) and nurse-written (7) PILs. Two instruments found that the 3 Information Standard hallmarked PILs had a higher (harder) readability than ordinary PILs (n = 82) (Gunning-Fog, p = .029*; SMOG p = .049*). CONCLUSION: Most English postoperative dermatological PILs' readability levels exceed recommendations (US grade ≤6). Departmental PILs should be reviewed to ensure that they are comprehensible to their patients.