Multiple Subclinical Syringomatous Proliferations Encountered during Mohs Surgery for Basal Cell Carcinoma

BACKGROUND: Examination of Mohs surgery frozen sections may lead to discovery of incidental benign neoplasms such as syringomas. OBJECTIVE: An unusual occurrence of numerous subclinical syringomatous proliferations discovered during Mohs surgery for a basal cell carcinoma that posed a diagnostic and management dilemma is reported. METHODS: Clinical records and histologic sections are examined. RESULT: Multiple syringomatous proliferations were noted around a basal cell carcinoma during Mohs surgery. A few foci were atypical appearing and focally extending into the deep dermis causing a diagnostic dilemma. All atypical syringomatous proliferations were excised. Evaluation of final Mohs margins by permanent sections and biopsies of normal-appearing facial skin showed multiple benign syringomas. CONCLUSION: Although solitary subclinical syringomas have been described in association with basal cell carcinomas, the occurrence of multiple syringomas and syringomatous proliferations has not been previously reported. Dermatologists should be aware of the existence of this phenomenon and consider permanent section evaluation to better determine nature of unusual incidental tumors identified in frozen sections during Mohs surgery.     

Peritumoral Fibrosis in Basal Cell and Squamous Cell Carcinoma Mimicking Perineural Invasion: Potential Pitfall in Mohs Micrographic Surgery

Background. Perineural invasion (PI) in cutaneous basal cell carcinoma (BCC) and squamous cell carcinoma (SCC) is linked to an aggressive course. We describe a histologic mimic for PI that we termed peritumoral fibrosis (PF).
Objective. To describe the morphologic changes associated with PF and to determine the incidence of PF and PI in Mohs frozen sections of BCC and SCC.
Material and Methods. All cases of BCC and SCC that were treated by Mohs micrographic surgery (MMS) at the Skin and Cancer Center, University of Florida College of Medicine, Gainesville, Florida, and the Center for Dermatology and Skin Surgery, Tampa, Florida, during the period from January 1, 2003, to August 1, 2004, were reviewed for the presence of PI and PF. The latter was defined as the presence of concentric layers of fibrous tissue that either surround and/or were surrounded by tumor formations mimicking perineural or intraneural invasion. Seven hundred six cases of BCC and 264 cases of SCC were surveyed. Eleven cases (10 BCC and 1 SCC) with equivocal areas were destained, and immunohistochemical staining with S-100 protein was performed, proving actual PI in all of these cases. Available original hematoxylin-eosin biopsy slides were correlated with the MMS frozen sections.
Results. PF was noticed in 4.5% of SCCs and 5.8% of BCCs. The incidence of unequivocal PI was noted to be 2.6% in SCC and 2.1% in BCC.
Conclusion. We describe a specific pattern of fibrosis noted in BCC and SCC that we called PF. It shows concentric layers of fibrous tissue surrounding and/or surrounded by tumor formations and resembles carcinomatous perineural and/or intraneural invasion. Moreover, PF was found to be a sensitive marker for PI. Mohs micrographic surgeons should be aware of this phenomenon to avoid triggering unnecessary steps in managing these cases, such as irradiation.     

Squamous Cell Carcinoma of the Auricle and Mohs Micrographic Surgery

Background. Squamous cell carcinoma (SCC) of the ear compared with SCC occurring at other skin sites has an increased incidence of recurrence following treatment.
Objective. To determine the following variables: patient age and gender, life status, tumor location, and recurrence rate following Mohs micrographic surgery (MMS).
Methods. The charts of 117 patients with 144 invasive SCCs of the auricle were reviewed. The patients were contacted by telephone to confirm tumor recurrence and patients' life status. The range of follow-up was 7 to 67 months (average 34.6 months) after MMS.
Results. The patients' ages ranged from 34 to 90 years (mean age 71 years). The male to female ratio was 22:1. The helix was the most common site of occurrence (50.7%). Local recurrence after MMS was found in four patients (five tumors). MMS was performed on these five recurrent tumors, with no further recurrences. Telephone confirmation was obtained on 91 patients (26 patients could not be contacted) with 122 tumors, which included the 4 patients with 5 recurrent tumors. There were no additional recurrences. Of these 122 tumors, 35 were followed for less than 2 years (average 16.6 months), and 87 were followed for 2 years or more (average 41.8 months). From the chart review and telephone contact, the 2-year local recurrence rate was 5.7% (5 of 87 tumors) after MMS. The average size of these 87 tumors was 3.5 cm2. Twelve of 91 patients had died with evidence of active disease from causes unrelated to SCC.
Conclusion. Invasive SCC of the ear was once a formidable disease with a severe prognosis. The course of this disease has been appreciably improved by early diagnosis and treatment with MMS.
SIRUNYA SILAPUNT, MD, S. RAY PETERSON, MD, AND LEONARD H. GOLDBERG, MD, FRCP, HAVE INDICATED NO SIGNIFICANT INTEREST WITH COMMERCIAL SUPPORTERS.     

Mohs Micrographic Surgery for Melanoma: A Case Series, a Comparative Study of Immunostains, an Informative Case Report, and a Unique Mapping Technique

BACKGROUND: Mohs micrographic surgery (MMS) has been established as an alternative to standard surgical excision for local cutaneous malignant melanoma (MM) and melanoma in situ (MIS). The use of melanocyte-specific immunohistochemical stains may improve the diagnostic accuracy of MMS frozen sections. OBJECTIVE: We used MMS with immunostains to determine the maximum and minimum margins required to clear 52 melanomas, mostly MIS of the head and neck. We sought to identify the most sensitive melanocyte immunostain for use in MMS frozen sections and to improve the clinicopathologic correlation of perilesional pigmented lesions. METHODS: We studied 52 consecutive cases of invasive melanoma (n = 10) and MIS (n = 42), tabulating the maximum and minimum margins required for complete tumor resection in any one direction during MMS. In 10 of these cases we studied the relative sensitivity of the immunostains MART-1, S-100, and HMB-45 in Mohs frozen sections. We describe a case highlighting the importance of the increased sensitivity of MART-1. In 12 patients we used a unique mapping technique to help determine the clinical relevance of a total of 35 perilesional pigmented foci. RESULTS: The maximum margin averaged 10.1 mm (range 3-26 mm) for MM and 9.4 mm (range 3-18 mm) for MIS. The minimum margin averaged 7.0 mm (range 3-13 mm) for MM and 5.5 mm (range 3-11 mm) for MIS. For individual tumors, the difference between the minimum and maximum margin averaged 3.7 mm (range 0-13 mm). This difference was >or=5 mm in 38% (20/52) and >or=10 mm in 10% (5/52), highlighting that subclinical tumor extension is often broad and asymmetric. While five of six MM less than 1.0 mm in depth would have been cleared with a routine 1 cm excision, a standard 5 mm margin would have cleared less than one-quarter of the cases of MIS (10/42). In Mohs frozen sections, MART-1 proved superior in sensitivity to both HMB-45 and S-100. Our mapping technique provided clinically relevant histologic correlation for perilesional pigmented lesions, improving the Mohs surgeon's ability to evaluate equivocal foci in frozen sections. CONCLUSION: MM, especially MIS on the head and neck, often exhibits an asymmetric growth pattern, making it quite suitable for treatment with MMS. The use of MART-1 immunostain may improve the diagnostic accuracy of Mohs surgeons. We believe that HMB-45 should not be used to rule out the diagnosis of MIS in equivocal sections because of its inferior sensitivity. We introduce a new mapping technique as an adjunctive measure to aid in the clinicopathologic evaluation of perilesional skin.     

Mohs Micrographic Surgery is Accurate 95.1% of the Time for Melanoma In Situ: A Prospective Study of 167 Cases

BACKGROUND Mohs micrographic surgery (MMS) represents a promising option for treatment of melanoma in situ (MIS). However, interpretation of melanocytic lesions by fresh frozen sections may be difficult.
OBJECTIVE The objective of this study was to determine if margins called clear by MMS were clear by subsequent paraffin-embedded sections and to compare cure rate with available data for MMS and standard excision.
MATERIALS AND METHODS A total of 167 patients with MIS, including 116 patients with MIS in sun-exposed skin of lentigo maligna (LM) type, were treated by MMS with subsequent evaluation of the final margin with paraffin-embedded sections that were cut en face, over a period of 12 years. A total of 143 patients were available for follow-up from 6 months to 12 years (mean, 50 months; median 48 months; 594.5 patient-years), and 109 patients were available for follow-up from 2 to 12 years (mean, 63 months; median, 60 months; 569 patient-years).
RESULTS The clearance rate by MMS technique using frozen sections was 94.1% for MIS non-LM type, 95.7% for MIS LM type, and 95.1% for both. The cure rate was 97.8% for MIS non-LM type, 99.0% for MIS LM type, and 98.6% for both for mean follow-up of 50 months and 97.4% for MIS non-LM type, 98.6% for MIS LM type, and 98.2% for both for mean follow-up of 63 months.
CONCLUSION MMS is a viable option for treatment of MIS that may increase cure rate and reduce the size of the defect especially in cosmetically and functionally sensitive areas.     

Outcomes of mohs microgrpahic resection for cutaneous malignancy involving the scrotum

IntroductionSquamous cell carcinoma (SCC) and extramammary Paget's Disease (EMPD) of the scrotum are exceedingly rare. Given their propensity for local invasion and treatment with wide local excision, they can be highly morbid conditions. Outcomes of Mohs Micrographic Surgery (MMS) for scrotal cutaneous malignancy is not well described in current literature. We hypothesized that MMS for scrotal cutaneous malignancy would provide equivalent or improved oncologic outcomes while limiting the morbidity associated with wide excision.Materials/MethodsThis is a retrospective review and analysis of a prospectively maintained database spanning entries from 2005 to 2019. Collected data included general patient characteristics and surgical characteristics reported on a per lesion basis. MMS was performed by our institution's department of dermatology using their standard technique.ResultsOverall, a total of 26 consecutive patients with 28 lesions (SCC or EMPD) were analyzed. Out of our cohort of 15 patients with 16 scrotal SCC lesions, 10 (66%) patients were current or former smokers, 4 (26%) were immunosuppressed, and 2 (13%) had HPV infections. The median preoperative and postoperative size of SCC lesions were 5.7cm [2] and 20.2cm [2] respectively. There was one (6%) oncologic recurrence of SCC of the scrotum and one (6%) local wound complication. Our cohort also included 11 patients with 12 scrotal EMPD lesions. One patient (9%) had an underlying associated malignancy (prostate cancer). The preoperative and postoperative area of lesions were 50.6cm [2] and 96.4cm [2] respectively. One (9%) EMPD lesion had a positive final margin at resection requiring reoperation. After achieving negative surgical margins, no patients in this cohort had an oncologic recurrence. 3 (26%) scrotal EMPD cases had local wound postoperative complications, only one required reoperation.ConclusionTo our knowledge, this is the first case series focused on MMS for both SCC and EMPD with scrotal involvement. Our data suggests that MMS for scrotal cutaneous malignancy may improve oncologic outcomes and may decreases local post-operative reconstructive issues when compared to reported outcomes of treatment with wide local excision. When able, scrotal cutaneous malignancy patients should be referred to urologists at centers with MMS capabilities as it likely will improve their outcomes. The urologist should maintain active involvement with these patients to coordinate this complex and advanced pattern of care.     

Mohs Micrographic Surgery in the Treatment of Rare Aggressive Cutaneous Tumors: The Geisinger Experience

BACKGROUND: Mohs micrographic surgery (MMS) offers high cure rates and maximum tissue preservation in the treatment of more common cutaneous malignancies, but its effectiveness in rare aggressive tumors is poorly defined. OBJECTIVE: Evaluate the effectiveness of MMS in the treatment of six rare aggressive cutaneous malignancies as seen by Mohs surgeons working at a referral center. METHODS: Retrospective chart review of 26,000 cases treated with MMS at the Geisinger Medical Center Department of Dermatology during a 16-year period with the following diagnoses: poorly differentiated squamous cell carcinoma (PDSCC), dermatofibrosarcoma protuberans (DFSP), microcystic adnexal carcinoma (MAC), extramammary Paget's disease (EMPD), Merkel cell carcinoma (MCC), and sebaceous carcinoma (SEB CA). Patient demographic data, tumor measurements, treatment characteristics, and marginal recurrence rates were compiled and evaluated. RESULTS: The mean numbers of cases identified per year for each tumor type were as follows: PDSCC, 6.19; DFSP, 2.44; MAC, 1.63; and EMPD, 0.63. For PDSCC, 85 cases were available for follow-up with a local recurrence rate of 6% at a mean follow-up time of 45 months. For DFSP, there were 35 cases with no local recurrence at a mean follow-up of 39 months. For MAC, there were 25 cases with a local recurrence rate of 12% at a mean follow-up of 39 months. For EMPD, there were 10 cases with no local recurrences at a mean follow-up of 34 months. CONCLUSIONS: Collectively, our data on PDSCC, DFSP, MAC, and EMPD, combined with other studies in the literature, show that MMS is the most effective therapy for these rare aggressive cutaneous malignancies.     

Post–Mohs Micrographic Surgical Margin Tissue Evaluation with Permanent Histopathologic Sections

Background. Incomplete resection of nonmelanoma skin cancer is associated with a relatively high rate of recurrent tumors. Mohs micrographic surgery provides microscopic evaluation of tumor margins to ensure complete excision of nonmelanoma skin cancers at high risk of recurrence.
Objective. This purpose of this study is to confirm the histologic accuracy of Mohs excision of facial skin cancers by evaluating an additional layer of tissue with permanent histopathologic sections after Mohs excision.
Methods. Two hundred ninety-six Mohs cases were identified, which, after excision, were sent to a single plastic surgeon for reconstruction. This plastic surgeon routinely takes an additional layer and sends for permanent histopathologic evaluation at the time of reconstruction. A review of the pathology reports and tissue specimens on these patients provides valuable data on tumor margins and the effectiveness of the Mohs technique for tumor excision.
Results. Two excisions of nodular basal cell cancer were determined by the pathologist to have positive tumor involvement on post-Mohs permanent tissue. On additional review, one specimen was interpreted to be more consistent with follicular epithelium, and the second was verified as a focus of nodular basal cell cancer.
Conclusion. These data support the high reliability of Mohs surgery for margin control.     

A Risk Scale for Predicting Extensive Subclinical Spread of Nonmelanoma Skin Cancer

BACKGROUND: The clinical appearance of nonmelanoma skin cancer may represent only a portion of microscopic tumor invasion. OBJECTIVE: To develop a scale based on high-risk characteristics for predicting the probability of extensive subclinical spread of nonmelanoma skin cancer. METHODS: Retrospective analysis of 1095 Mohs micrographic surgical cases (MMS) yielded high-risk factors for extensive tumor spread, defined as requirement of greater-than-or-equal3 MMS layers. Predictive characteristics included: any BCC on the nose, morpheaform BCC on the cheek, neck tumors and recurrent BCC in men, location on the eyelid, temple, or ear helix, and size>10 mm. Multivariate logistic regression was applied to develop a risk index. RESULTS: Tumor characteristics were assigned point values calculated from the respective odds of extension and categorized into six risk classes with probabilities of extensive subclinical spread ranging from 10% to 56%. CONCLUSION: A risk scale simplifies and enhances prediction of extensive tumors. The associated probabilities can help to guide patient preparation and appropriate therapy.     

Mohs Micrographic Surgery for Granular Cell Tumor Using S-100 Immunostain

BACKGROUND: Granular cell tumor (GCT) is an uncommon tumor of neural origin. Most commonly it is found in the head and neck region and rarely on the foot. The pathologic diagnosis is often confirmed by immunohistochemical staining for S-100 protein. The standard treatment is complete excision. Two previous cases of GCTs treated by Mohs micrographic surgery (MMS) have been reported in the English literature. The immunohistochemical stain S-100 was not used in these cases. OBJECTIVE: Describe the use of S-100 immunohistochemical stain on MMS frozen sections in clearing a GCT of the foot with extension along nerves without involvement of perineurium. METHODS: Tissue was embedded and cut using standard Mohs surgical methodology. Frozen sections were stained with hematoxylin and eosin and with an immunoperoxidase method for S-100 protein using a Ventana automated stainer. RESULTS: MMS in combination with S-100 was successfully performed on a GCT on the plantar surface of our patient's foot. The S-100 immunohistochemical stain was helpful in tracking the extension along nerves of the GCT which was not evident with hematoxylin and eosin alone. CONCLUSION: Using S-100 immunohistochemical stain on the MMS frozen sections can increase the diagnostic accuracy for complete removal of GCT.     

Immunostaining Melanoma Frozen Sections: The 1-Hour Protocol

BACKGROUND: There is significant debate over the use of frozen section processing in Mohs micrographic surgery (MMS) for melanoma. Opponents argue that individual melanocytes are too subtle to view consistently on frozen sections. On the other hand, proponents state that (1) melanocytes are visible on well-prepared frozen sections and (2) MMS using frozen sections for evaluation of melanoma surgical margins achieves comparable recurrence rates when compared with MMS using paraffin-embedded, permanent sections. OBJECTIVE: To introduce a new immunohistochemical (IHC) staining protocol that consistently produces melanoma frozen section slides in 1 hour that are easily evaluated during MMS. METHODS: We adapted a polymer-based IHC staining protocol to use with MMS frozen sections for the evaluation of melanoma surgical margins. RESULTS: When used with antibody directed against MART-1 for frozen section evaluation of melanoma, the section staining is reproducible and specific for melanocytes. CONCLUSIONS: In contrast to current IHC protocols that are time consuming (2 to 2.5 hours), we present a new frozen section protocol that takes approximately 1 hour to perform. This technique benefits patients, histotechnicians, and surgeons.     

Lymphocytic Infiltrates and Subclinical Epithelial Tumor Extension in Patients With Chronic Leukemia and Solid-Organ Transplantation

BACKGROUND: Dense infiltrates in association with squamous cell carcinoma (SCC) or basal cell carcinoma (BCC) in patients with underlying chronic lymphocytic leukemia (CLL) may complicate pathologic interpretation of histologic margins. OBJECTIVE: The study was conducted to determine the frequency of identifying dense inflammatory infiltrates in frozen histologic sections during Mohs operation for BCC or SCC in patients with CLL and organ-transplant recipients, to characterize the infiltrate (reactive versus leukemic) in CLL, and to estimate the subclinical tumor extension in patients with CLL, transplant recipients, and control subjects undergoing Mohs procedure. METHODS: Frozen sections of head and neck BCC and SCC obtained during Mohs procedures in patients with CLL, organ transplant recipients, and a control group were reviewed retrospectively. Biopsy specimens of CLL with dense infiltrates were assessed with immunohistochemical stains. Subclinical tumor extension (postoperative defect size minus preoperative tumor size) was evaluated in each group. RESULTS: Dense infiltrates were found in tumors of 20 of 55 patients with CLL (36%), 1 of 8 transplant recipients (13%), and 1 of 105 controls (1%). In patients with CLL, 75% of the dense infiltrates were B-cell leukemic. Compared with controls, the mean subclinical tumor extension was larger in patients with CLL (P=0.029) and in transplant recipients (P=0.55). CONCLUSION: Dense leukemic infiltrates associated with BCC or SCC in CLL may complicate pathologic interpretation of Mohs surgical histologic margins and may be associated with larger postoperative defects relative to preoperative clinical tumor appearance. In patients with CLL, as in transplant recipients, SCC seems more likely to develop than BCC.     

Treatment of Dermatofibroma Sarcoma Protuberans Using Modified Mohs Micrographic Surgery: No Recurrences and Smaller Defects

OBJECTIVES The purpose of this study was to evaluate the use of modified Mohs micrographic surgery (MMS) for dermatofibromasarcoma protuberans (DFSP) in a single institution by a single surgeon.
METHODS The authors conducted a retrospective analysis of 25 patients with DFSP who were treated with modified MMS over the past 19 years at Scripps Clinic.
RESULTS Of the 25 patients treated with modified MMS for DFSP, there were no identifiable recurrences. The mean follow-up time was 101 months. The defect sizes of DFSP lesions treated by modified MMS are smaller than if the lesions had been treated with the standard wide local excision (WLE) margins of 3 cm.
LIMITATIONS This is a retrospective analysis using the data of one surgeon. Five of the 25 patients were not examined in our office. Not all patients had 5-year follow-up. There were no cases of the fibrosarcomatous variant.
CONCLUSION Our data support the growing literature that modified MMS achieves excellent local control for DFSP with a possible benefit of smaller defects when compared with treatment with WLE.     

Presurgical Curettage Appropriately Reduces the Number of Mohs Stages by Better Delineating the Subclinical Extensions of Tumor Margins

Background. Whether presurgical curettage (PC), light curettage performed before Mohs surgery to delineate tumor margin, is appropriate or causes unnecessary removal of normal tissue has not been well established.
Objective. We aim to determine histologically whether PC appropriately increases the size of the stage I specimen or causes unnecessary removal of healthy tissue.
Methods. Before a surgical margin guided by PC was taken, a hypothetical margin determined by visual and tactile assessment alone (no curettage [NC]) was marked outside the clinically defined tumor. Histologic analysis at the NC and the PC margins revealed whether the increase in the stage I specimen as a result of PC was appropriate.
Results. PC appropriately increased the stage I specimen in 21 cases and unnecessarily removed normal tissue in only 1 case. The estimation of tumor margins with PC was 15 times more accurate than with NC (p value = .0012).
Conclusion. For basal cell and squamous cell carcinomas at least 4 mm in diameter, light curettage performed prior to Mohs surgery could better delineate subclinical extensions of the tumor margin and appropriately increase the size of the stage I specimen.     

Mohs Micrographic Surgery Referral Patterns: The University of Missouri Experience

Background. Mohs micrographic surgery (MMS) provides a higher cure rate for nonmelanoma skin cancer (NMSC) than other forms of therapy. The American Academy of Dermatology has published recommended guidelines for MMS referral. However, factors other than the location, size, and type of NMSC may often affect the referral process.
Objective. To tabulate and analyze the rates of referral of NMSC for MMS by the dermatology clinics within the University of Missouri system. Data obtained for every biopsy-proven basal cell carcinoma (BCC) and squamous cell carcinoma (SCC) diagnosed at each of our four dermatology clinics during the 3-year period of October 1993–September 1996 were cross-referenced with our Mohs surgery clinic logbook to identify which patients had been referred for MMS.
Results. During the study period, 19.2% of NMSC patients diagnosed were referred for MMS. However, there was significant disparity in referral rates among our four clinics. When the skewed data from our Veterans Administration Hospital clinic were discounted, the overall referral rate from the other clinics was found to be 30.8%.
Conclusion. Our finding of a 30.8% referral rate of NMSC for MMS (27.4% for SCC and 32.9% for BCC) within our university dermatology system is similar to the rates found in previous studies by the Mayo Clinic and Brooke Army Medical Center. MMS referral patterns are affected by many factors besides whether the NMSC meets MMS criteria, including the preference of each individual referring physician, patient, and involved insurance carrier.     

Merkel Cell Carcinoma: Spontaneous Resolution and Management of Metastatic Disease

Background. Merkel cell carcinoma (MCC) is a rare, aggressive, cutaneous neoplasm. The primary form of initial treatment is wide surgical excision. The use of Mohs micrographic surgery as the primary form of treatment in MCC has been controversial. The course of MCC is often aggressive, with early metastasis, widespread disease, and death. Despite the poor prognosis, spontaneous regression has occasionally been reported.
Objective. We describe the clinical course of two patients with Merkel cell carcinoma who underwent treatment with Mohs micrographic surgery for the primary MCC. Metastases were excised in the first case and spontaneously regressed in the second. Both patients are without clinical disease at the time of this report.
Methods. Histopathology, clinical records, and the current literature are reviewed.
Results. One patients was without recurrence of MCC for 13 years of follow-up. The other patient experienced clinical spontaneous remission after nodal spread of the disease, with no recurrence for 18 months after clinical remission and 24 months after surgery.
Conclusion. The treatment of Merkel cell carcinoma with Mohs micrographic surgery (MMS) has been successful for the control of primary skin disease, and is at least comparable to wide excision. Spontaneous regression may occur in the course of this usually relentless and aggressive disease. The explanation for spontaneous regression of MCC is unknown.     

Microcystic Adnexal Carcinoma (MAC) of the Scalp with Extensive Pilar Differentiation

BACKGROUND: Microcystic adnexal carcinoma (MAC), or sclerosing sweat duct tumor, is an uncommon, locally aggressive tumor. It typically involves the upper lip or face of middle-aged adults and rarely involves the scalp. It is characterized histologically by both pilar and eccrine differentiation and is associated with frequent perineural invasion. MAC is frequently misdiagnosed because of its bland and asymptomatic clinical presentation. In addition, its defining histologic features may be missed with a superficial biopsy. OBJECTIVE: To describe a case of MAC in the scalp treated with Mohs surgery. We describe a case with extensive pilar differentiation and clear cell changes. In addition, the clinical and histologic characteristics of this rare neoplasm are reviewed. METHODS: Mohs micrographic surgery (MMS) was performed on this neoplasm. RESULTS: The tumor was successfully excised in one surgery (five stages) and is without evidence of recurrence at 18 months. CONCLUSION: We present a case of MAC of the scalp in a 64-year-old white man treated successfully with MMS.     

Innovative Laboratory Techniques to Facilitate Processing of Large Mohs Cases

Background Processing multiple tissue sections in large Mohs cases is time consuming and labor intensive.
Objective To present innovative laboratory techniques to facilitate processing of large Mohs cases.
Methods A method for processing a large dermatofibrosarcoma protuberans Mohs case is outlined.
Results Modifications in tissue processing and equipment employed in a large Mohs case are presented.
Conclusion Innovative modifications to the standard Mohs laboratory technique can facilitate processing of large Mohs cases, resulting in high-quality, rapid frozen sections while optimizing efficiency.     

Sebaceous Carcinoma of the Eyelids Treated by Mohs Micrographic Surgery: Report of Nine Cases with Review of the Literature

BACKGROUND: Ocular sebaceous carcinoma (SC) is a rare tumor of the eyelids. Clinically it frequently involves the upper lid in older women. Microscopically it tends to extend far beyond its assessed clinical margins. SC is characterized by a variety of tissue invasion mechanisms. It may spread by direct extension, be multifocal in advanced cases, and develop "skip areas" after trauma. Despite its ability to develop discontinuity, over the past two decades there have been several favorable case reports of SC treated by Mohs micrographic surgery (MMS). OBJECTIVE: To illustrate by case report the clinical presentation and management of patients with SC and to document our series of SC patients treated by MMS over the last 14 years. METHODS: A retrospective study was conducted of all cases of sebaceous carcinoma involving the ocular adnexa treated at the University of Wisconsin Mohs Surgery Clinic from 1987 to 2001. We also reviewed the accumulated medical literature of SC treated by MMS. RESULTS: In our series, there were nine cases of periocular SC. Five cases originated on the upper lid and four on the lower lid. Five of nine patients (55%) showed epithelial invasion. One patient developed a local recurrence 1.5 years later and was treated by orbital exenteration. This patient has had no evidence of disease for 5 years. Eight of nine patients (88%) had no evidence of local recurrence with a follow-up of 1-14 years. In our literature review we found 40 additional cases of orbital SC treated by MMS. Intraepithelial spread of SC was found in 50% of patients (24 of 48). Six patients developed local recurrence. The overall local cure rate following MMS is 87.8% (43 of 49), with a mean follow-up of 3.1 years. The regional metastatic rate was 8% (4 of 49). There were no deaths reported. CONCLUSION: We present nine new cases of SC. The age, sex, and site distribution are compatible with other SC cases reported in the literature. We reviewed the medical literature and compiled 49 cases of SC treated by Mohs surgery. Intraepithelial spread was discovered in 50% of the cases. Multifocal disease or discontinuity was present in 6% (3 of 49). Mohs surgery appears to be an effective method for excising the microscopic ramifications of primary SC. When feasible, we recommend in SC cases where intraepithelial pagetoid spread has been observed, that removal of another Mohs layer should be considered in order to provide an additional assurance layer against local tumor recurrence.     

In Vivo Real-Time Confocal Reflectance Microscopy: A Noninvasive Guide for Mohs Micrographic Surgery Facilitated by Aluminum Chloride, an Excellent Contrast Enhancer

BACKGROUND: Mohs micrographic surgery (MMS) is based on microscopically controlled excision of cutaneous neoplasms and offers the highest cure rates with maximum tissue preservation. In vivo confocal microscopy (CM) allows noninvasive optical imaging of thin sections of living skin, in its native state, in real time, with high resolution and contrast. OBJECTIVE: To evaluate the feasibility of the use of in vivo CM as a surgical guide in MMS. METHODS: Five patients with a biopsy-proven basal cell carcinoma (BCC) were imaged by in vivo CM on one or two sites from the clinically visible skin cancer. The first Mohs layer was then excised, and the fresh-frozen sections were correlated with the CM findings. Aluminum chloride (AlCl) 20% was applied on the Mohs defect followed by in vivo CM on one site from each lesion. A second Mohs layer was subsequently excised, and fresh-frozen sections were correlated with CM findings. RESULTS: The findings of in vivo CM were confirmed by hematoxylin and eosin-stained frozen sections after excisions of the first and second Mohs layers. AlCl was found to provide an excellent contrast between BCC cells and the surrounding tissue, detected readily with both in vivo and ex vivo CM. The tumor cells with AlCl exhibited intensely bright nuclei with an excellent contrast as compared with the low-contrast dark nuclei without AlCl application. CONCLUSION: In vivo CM is a potential surgical guide for MMS, and AlCl provides an excellent exogenous agent to enhance tumor contrast for CM.