David G. Brodland

Surgical margins for excision of primary cutaneous squamous cell carcinoma

BACKGROUND No guidelines for the margin of resection of cutaneous squamous cell carcinoma have been based on data measuring subclinical tumor extension, as have been formulated for basal cell carcinoma. OBJECTIVE AND METHODS Guidelines for appropriate margins of excision of primary cutaneous squamous cell carcinoma were formulated on the basis of a prospective study of subclinical microscopic tumor extension. RESULTS Four millimeter margins were adequate for most squamous cell carcinomas. However, certain tumor characteristics were associated with a greater risk of subclinical tumor extension and included size of 2 cm or larger, histologic grade 2 or higher, invasion of the subcutaneous tissue, and location in high-risk areas. CONCLUSION Minimal margins of excision of 4 mm around the clinical borders of the squamous cell carcinoma are proposed for all but the high-risk tumors, in which at least a 6 mm margin is recommended.

The epidemiology of skin cancer

BACKGROUND The incidence of skin cancer is increasing at an alarming rate. OBJECTIVE To discuss current epidemiologic data concerning the incidence, morbidity, environmental influences, predisposing, host conditions, precursor lesions, and prevention of melanoma and nonmelanoma (basal and squamous cell) skin cancer. METHODS The current literature ions reviewed in order to provide current epidemiologic data for melanoma, basal cell carcinoma (BCC), mid squamous cell carcinoma (SCC). RESULTS Skin cancer is exceedingly common and the incidence is rising rapidly. Although the mortality rate for nonmelanoma skin cancer (NMSC) is decreasing, that of melanoma is increasing. Both NMSC and melanoma are associated with significant morbidity. Whereas chronic sun exposure is the main cause of NMSC, the development of melanoma appears to be related to intense, intermittent sun exposure. Ozone depletion has contributed to rising incidence rates of both NMSC and melanoma. In contrast to NMSC, there is not a direct relationship between ultraviolet radiation and melanoma. Genetic susceptibility significantly increases the lifetime risk of acquiring melanoma. There is no precursor lesion for BCC. Precursor lesions for invasive SCC include actinic keratoses and SCC in situ. Melanoma may arise from benign nevi and dysplastic nevi. Prevention of melanoma and NMSC is extremely important since prognosis improves with early detection. Prevention may be achieved by educating patients and physicians how to detect skin cancers early and by decreasing or eliminating exposure to ultraviolet light. CONCLUSION The incidence of skin cancer has readied epidemic proportions. Only through heroic efforts by health care professionals and the general public to prevent the development or progression of skin cancer will this epidemic be abated. Dermatol Surg 1996;22:217‐226.

Merkel cell carcinoma. Comparison of Mohs micrographic surgery and wide excision in eighty-six patients.

BACKGROUND. Merkel cell carcinoma is an uncommon malignant tumor of the skin that, after standard surgical excision, tends to recur locally and develop regional nodal spread. OBJECTIVE. This study evaluated the use of Mohs micrographic surgery for this aggressive neoplasm. METHODS. A retrospective study of 86 patients with Merkel cell carcinoma established rates of local persistence and the development of regional metastasis after standard surgical excision. Detailed follow‐up was availake on a subgroup of 13 patients treated with Mohs surgery. RESULTS. Standard surgical excision for local disease was associated with high rates of local persistence (13 of 41 [31.7%]) and regional metastasis (20 of 41 148.8%]). Mean follow‐up was 60 months. Mean follow‐up for the group treated with Mohs was 36 months. Only one of 12 (8.3%) Mohs‐treated patients with histologically confirmed clearance has had local persistence of disease. This patient underwent a second Mohs excision and has remained disease free for 84 months. Regional metastasis devel‐oped in four of 12 cases (33.3%). Regional metastasis developed in none of the four patients treated with radiotherapy after Mohs surgery and in four of eight patients treated with Mohs surgery without postoperative radiotherapy. CONCLUSION. Mohs surgery compares favorably with standard surgical excision. Radiotherapy after Mohs surgery may further reduce persistent metastases in transit and nodal disease.

AAD/ACMS/ASDSA/ASMS 2012 appropriate use criteria for Mohs micrographic surgery: A report of the American Academy of Dermatology, American College of Mohs Surgery, American Society for Dermatologic Surgery Association, and the American Society for Mohs Surgery

The appropriate use criteria process synthesizes evidence-based medicine, clinical practice experience, and expert judgment. The American Academy of Dermatology in collaboration with the American College of Mohs Surgery, the American Society for Dermatologic Surgery Association, and the American Society for Mohs Surgery has developed appropriate use criteria for 270 scenarios for which Mohs micrographic surgery (MMS) is frequently considered based on tumor and patient characteristics. This document reflects the rating of appropriateness of MMS for each of these clinical scenarios by a ratings panel in a process based on the appropriateness method developed by the RAND Corp (Santa Monica, CA)/University of California-Los Angeles (RAND/UCLA). At the conclusion of the rating process, consensus was reached for all 270 (100%) scenarios by the Ratings Panel, with 200 (74.07%) deemed as appropriate, 24 (8.89%) as uncertain, and 46 (17.04%) as inappropriate. For the 69 basal cell carcinoma scenarios, 53 were deemed appropriate, 6 uncertain, and 10 inappropriate. For the 143 squamous cell carcinoma scenarios, 102 were deemed appropriate, 7 uncertain, and 34 inappropriate. For the 12 lentigo maligna and melanoma in situ scenarios, 10 were deemed appropriate, 2 uncertain, and 0 inappropriate. For the 46 rare cutaneous malignancies scenarios, 35 were deemed appropriate, 9 uncertain, and 2 inappropriate. These appropriate use criteria have the potential to impact health care delivery, reimbursement policy, and physician decision making on patient selection for MMS, and aim to optimize the use of MMS for scenarios in which the expected clinical benefit is anticipated to be the greatest. In addition, recognition of those scenarios rated as uncertain facilitates an understanding of areas that would benefit from further research. Each clinical scenario identified in this document is crafted for the average patient and not the exception. Thus, the ultimate decision regarding the appropriateness of MMS should be determined by the expertise and clinical experience of the physician.

Surgical margins for melanoma in situ

BACKGROUND A controversy in the treatment of melanoma in situ is the required width of surgical margin. The currently accepted 5-mm margin is based on a 1992 consensus opinion, despite data since then showing this is inadequate. OBJECTIVE We sought to develop guidelines for predetermined surgical margins for excision of melanoma in situ. METHODS A prospectively collected series of 1072 patients with 1120 melanoma in situs was studied. All lesions were excised by Mohs micrographic surgery with frozen-section examination of the margin. The minimal surgical margin was 6 mm, and the total margin was calculated by adding an additional 3 mm for each subsequent stage required. The minimum surgical margin that would successfully remove 97% of all tumors was calculated. Local recurrence was also tabulated. RESULTS In all, 86% of melanoma in situs were successfully excised with a 6-mm margin; 9 mm removed 98.9% of melanoma in situs. The superiority of 9-mm to 6-mm margins was significant (P < .001). Gender, location, and diameter did not affect results. Recurrence rate for this set of patients treated with Mohs micrographic surgery was 0.3% (n = 3). LIMITATIONS Margins less than 6 mm were not studied. This is a referral center for melanoma in situ and 10% of tumors were previously treated before presentation to our clinic. CONCLUSION The frequently recommended 5-mm margin for melanoma is inadequate. Standard surgical excision of melanoma in situ should include 9 mm of normal-appearing skin, similar to that recommended for early invasive melanoma.

A Comparison of Mohs Micrographic Surgery and Wide Excision for the Treatment of Atypical Fibroxanthoma

background Atypical fibroxanthoma (AFX) is an uncommon spindle cell neoplasm occurring most often in actinically damaged skin of elderly patients. This tumor has invasive potential, may recur locally after excision, and rarely metastasizes. To conserve tissue and improve the likelihood of cure, Mohs micro–graphic surgery (MMS) has been used for treatment. objective We review and discuss the Mayo Clinic experience treating AFX with MMS and retrospectively compare the clinical outcome with that in a similar cohort of patients treated with wide local excision (WE). methods The medical records of 45 patients were reviewed at three Mayo Clinic practices. Follow–up data were available for 44 patients: 19 treated with MMS and 25 with WE. results In patients treated with MMS, there were no recurrences after a mean follow–up of 29.6 months. There were three first recurrences in 25 patients (12%) treated with WE after a mean follow–up of 73.6 months. One patient had a single local recurrence, and two patients each had two local recurrences. Parotid node metastasis eventually developed in one of the patients with two local recurrences, so that the regional metastatic rate in this series was 4% (1 in 25 patients). conclusion Microscopic control of the surgical margins with MMS in the treatment of AFX results in a lower recurrence rate than that with WE and conserves normal tissue.

Mechanisms of metastasis

The role of dermatologists in the diagnosis and treatment of skin cancer continues to increase. Consequently, they will more frequently be involved in the diagnosis, treatment, and management of patients with metastatic or potentially metastatic tumors. Squamous cell carcinomas and malignant melanomas are frequently seen in dermatologic practices and have the capability to metastasize. Metastases are the result of a complex process that is characterized by a sequence of steps, each of which requires acquisition by the malignant cell of key biologic properties. The metastatic sequence can be conceptualized as detachment from the primary tumor followed by invasion, intravasation into a vessel, circulation, stasis within a vessel, extravasation, invasion of the recipient tissue bed, and ultimately proliferation. The basic steps of the metastatic sequence are described as well as how these steps and other tumor cell adaptations can affect the clinical patterns of metastasis. Finally, practical applications of the understanding of these principles of metastasis are discussed.

Cutaneous micrographic surgery : mohs procedure

Skin cancer is an increasingly serious public health issue that affects a high percentage of the population. Surgical resection is still standard treatment for skin cancer, but for difficult cases, cutaneous micrographic surgery, originally described by Mohs, is our preferred technique because of the routine methodic accuracy for evaluation of the surgical margin, the high rate of oncologic cure, and the tissue-sparing quality of the procedure. We report the Mayo Clinic experience with cutaneous micrographic surgery from July 29, 1986, through June 30, 1991, which consisted of 3,355 cases (principally basal cell and squamous cell carcinoma). Herein we discuss practical concerns about this procedure: duration of the technique, reconstruction, cure rates, tumors best treated by cutaneous micrographic surgery, and cost. In addition, we review the Mayo Clinic multidisciplinary management of difficult skin cancers.

Dermabrasive scar revision. Immunohistochemical and ultrastructural evaluation.

BACKGROUND Dermabmsion of facial scars 4–8 weeks after injury frequently completely eliminates visible evidence of scar formation. However, efforts to define the cellular and structural mechanisms by which this phenomenon occurs have been limited in their success. OBJECTIVE We investigated wound healing after dermabrasive scar revision. METHODS The surgical scars of seven patients were abraded 6–8 weeks after injury. Comparative electron microscopic and immunohistochemical studies were performed on punch biopsy specimens taken before and after the dermabrasion. Ultrastructural changes in the basement membrane components and dermal structures were evaluated. Monoclonal antibody staining techniques were used to observe the presence, location, and temporal expression of tenascin, epiligrin, cadherins, and integrin subunits. RESULTS We observed: 1) an increase in collagen bundle density and size with a tendency toward unidirectional orientation of fibers parallel to the epidermal surface, 2) an upregulation of tenascin expression throughout the papillary dermis, and 3) expression of &agr;‐6/&bgr;‐4 integrin subunit on the keratinocytes throughout the stratum spinosum. CONCLUSIONS The mechanisms by which dermabrasive scar revision alters the events of primary cicatrix formation include modification of extracellular ligand expression, thereby influencing epithelial cell‐cell interaction, and reorganization of connective tissue.

Giant basal cell carcinoma (T3): Who is at risk?

Background. Giant basal cell carcinomas can cause extensive local invasion and disfigurement. This study determines in whom giant basal cell carcinomas develop.