Mohs surgery in the management of cutaneous malignancies

Anatomic Location Influences Duration of Local Lidocaine Anesthesia in Dermatologic Surgery

BACKGROUND

Although the onset and duration of local anesthetics are well-defined, how the anatomic site influences the duration of local anesthetics has not been well characterized in dermatology.

OBJECTIVE

To define the duration of local anesthesia by anatomic site.

MATERIALS AND METHODS

This was a prospective study. Adult healthy volunteers and patients undergoing Mohs micrographic surgery were invited to participate. The nose and the shin were chosen to represent highly and poorly vascularized anatomic sites, respectively. A total of 0.5 mL of buffered 1% lidocaine hydrochloride with 1:100,000 epinephrine was injected subcutaneously into each anatomic site of each participant. A pinprick test was used to assess adequate anesthesia until return of baseline sensation or visit completion.

RESULTS

This study enrolled 25 participants. Time to return of sensation was significantly shorter on the nose compared with the shin ( p < .0001). On the nose, there was an association between male sex and shorter time to return of sensation.

CONCLUSION

Time to return of sensation is significantly shorter on the nasal ala compared with the shin, suggesting that patients may regain sensation sooner on highly vascularized sites. Defining the duration of local anesthetics based on anatomic regions is important for treatment planning in dermatologic procedures.

Recurrence rate of basal cell carcinoma in patients submitted to skin flaps or grafts

BACKGROUND

Basal cell carcinoma is the most common type of skin cancer. Although the literature provides a great deal of information on the recurrences of basal cell carcinoma, studies about these indices addressing only the cases in which flaps and/or grafts have been performed for surgical reconstruction of the excision of this tumor are still lacking.

OBJECTIVES

To evaluate rates of recurrence of basal cell carcinoma submitted to conventional surgery with pre-established margins and reconstruction by flaps or grafts.

METHODS

A retrospective and observational study was performed through the analysis of 109 patients, who met inclusion criteria with 116 basal cell carcinomas submitted to conventional surgery and pre-established safety margins, requiring reconstruction through a graft or cutaneous flap. This work was performed the small surgeries sector of Dermatology of the Specialty Outpatient Clinic of the University Hospital of the State University of Londrina, between January 1, 2011 and December 31, 2015. The following data were collected and inserted in an Excel worksheet: name, registration number of the hospital patient, sex, age, tumor location, histopathological type of BCC, procedure performed (type of flap and/or graft), follow-up time, recurrence.

RESULTS

Of the 116 procedures, there were recurrences in 3 cases (2.6%) that were located in the nasal region and related to sclerodermiform or micronodular histological types.

STUDY LIMITATIONS

Retrospective nature of the study.

CONCLUSION

The present study of the dermatology department of this university hospital showed a low rate of recurrence of basal cell carcinoma in cases where flaps and/or grafts were used in the surgical reconstruction.

Appropriate use criteria for basal cell carcinoma Mohs surgery at a single center in the face of high-burden skin cancer: a retrospective cohort study

BACKGROUND

Mohs micrographic surgery (MMS) promotes high cure rates, but accessibility to MMS is limited in distinctive realities and countries.

OBJECTIVE

We sought to verify applicable criteria for MMS indication and prioritization regarding basal cell carcinoma (BCC) in the face of various limitations.

METHODS

We analyzed MMS-excised BBC, without patient exclusion, through a retrospective cohort study at a single university center.

RESULTS

Mohs micrographic surgery was performed in 101 BCCs, average size = 5.44 ± 11.91 cm², 56.44% ≥ 20 mm. Most BCCs were in the H-zone (87.13%) and on the nose (52.47%). Histology showed high-risk pattern in most of tumors (69.31%), primary (64.71%), and recurrent (74.0%) BCC. Nasal (p = .01) and recurrent BCC (p = .03) had increased risk for two or more MMS stages. Appropriate use criteria were considered for all cases of BCC removed by a single stage (60.40%), two or more stages (39.60%), and three or more MMS stages (10.89%). The latter two conditions were associated with a higher number of MMS criteria (p = .02; p = .03, respectively).

CONCLUSIONS

All excised BCCs fulfilled criteria for MMS indication, among them recurrent and nasal BCCs stood out. The greater number of criteria may be a predictive factor for subclinical extension and can help prioritize indications for MMS.

Mohs versus surgical excision in nonmelanoma skin cancers: does location matter?

INTRODUCTION

Every year, nearly 1.2 million people are affected by nonmelanoma skin cancers (NMSCs) in the United States. Most published data focus on comparing the efficacy of Mohs micrographic surgery (MMS) versus traditional surgical excision (TSE) for NMSCs in H-zone lesions of the face. There is paucity of data regarding the 2 treatments in other areas such as the non-H-zone areas of the face, the trunk, and extremities. Our study focused on the efficacy of the 2 treatments in areas of the body where the skin was not of premium.

METHOD

A retrospective chart review was performed of patients with NMSCs treated with TSE at the West Los Angeles Veterans Affairs Hospital between 2000 and 2008. Patients with at least a 3-year follow-up were selected for the study. Institutional review board approval was obtained before commencement of the study. Age, sex, and race-matched patients were selected in the MMS group. Data collected included demographic data, tumor characteristics, surgical treatment, reconstructions, recurrence rates, complications, and follow-up course. Data were analyzed using SigmaStat 3.5.

RESULTS

A total of 588 patients were treated for NMSCs at our institute between 2000 and 2008, of which 289 patients had non-H-zone, extremity, and trunk lesions. The follow-up period for these patients was at least 3 years. Average age of this group was 67.1 (11.4) with 89.9% being males. Age, sex, and race-matched group of 200 patients treated with MMS for NMSCs were randomly chosen from the same time range. Average size of lesions was 17.4 (16.9) mm in the TSE group and 1.1 (0.4) mm in the MMS group (P < 0.05). Primary reconstruction was performed in non-premium areas (ie, non-H-zone areas of the face, the trunk, and extremities) in 98.7% patients in the TSE group and 61.5% patients in the MMS group (P < 0.05). Secondary reconstructive rate was 1.3% in TSE compared to 37.5% in MMS. Overall recurrence rate was 4.8% (compared to 3% with MMS). Of the 29 patients who had recurrences within the TSE group, 27 were H-zone lesions and 2 were non-H-zone lesions.

DISCUSSION

One of the primary goals of NMSC management is to treat the lesion with adequate oncologic margins, while preserving maximal function and cosmesis. Our data look at the non-premium areas to quantify the clinical efficacy of TSE versus MMS. The size of lesions treated by TSE was significantly larger than those treated by MMS in all areas of the body. The primary closure rates were significantly higher and secondary procedure rates significantly lower in the TSE group compared to the MMS group, in non-premium areas. Our data suggest that patients with NMSCs may be more effectively treated with TSE than MMS in non-premium areas of the body. Additional studies are ongoing, including economic modeling and cost analysis.

Diagnosis and management of lentigo maligna: a review

Lentigo maligna is a melanocytic neoplasm occurring on sun-exposed skin, usually on the head and neck, of middle-aged and elderly patients. It is thought to represent the in situ phase of lentigo maligna melanoma. The ill-defined nature and potentially large size of lesions can pose significant diagnostic and treatment challenges. The goal of therapy is to cure the lesions in order to prevent development of invasive disease, and surgical excision is the treatment of choice to achieve clear histological margins. Nonsurgical treatment modalities have been reported; however, evidence is lacking to support their use. Age, general health, and comorbidities need to be taken into account when deciding the right treatment modality for each individual patient.

Obtaining high cure rates for challenging facial malignancies: A new method for producing rapid, accurate, high-quality frozen sections

PURPOSE

The authors developed a new system to provide rapid, accurate, full-face frozen sections.

OBJECTIVE

To evaluate the efficacy of the system when applied to the treatment of nonmelanoma cutaneous malignancies using Mohs micrographic surgery (MMS).

METHODS

Patients undergoing MMS procedures between 2003 and 2007 for nonmelanoma head and neck cutaneous malignancies were prospectively collected. Specimens were prepared either in a traditional cryostat-based manner or using the new system.

RESULTS

A total of 196 patients with 234 head and neck nonmelanoma cutaneous malignancies were included. The majority of tumours were basal cell carcinomas (89.5%). Of these, 38% demonstrated aggressive histologies (sclerosing or micronodular), and 30% were recurrent. On average, two levels (range one to six) and four blocks (range two to 23) were required to obtain clear margins. The mean defect size was 3.68 cm(2) (range 0.13 cm(2) to 37.68 cm(2)). Over the five-year study period, there were two recurrences in 234 cases (less than 1%), which compares favourably with other MMS series. The new system was associated with a shorter operative time than traditional specimen preparation (102 min versus 131 min; P=0.004). The new and traditional specimen preparation groups were similar in terms of the number of previous recurrences (29% versus 30%; P=1.00), defect size (3.7 cm(2) versus 4.0 cm(2); P=0.81) and the number of levels required (1.9 versus 1.5; P=0.05).

CONCLUSIONS

The new system enables fast, accurate, full-face frozen section specimens that are ideal for MMS. The speed of specimen preparation is demonstrated by faster operative times, and a low recurrence rate attests the accuracy and quality of the sections.

Mohs micrographic surgery for the management of nonmelanoma skin cancers

Many treatment modalities have been described to address the growing epidemic of nonmelanoma skin cancer (NMSC). Mohs micrographic surgery (MMS) is a surgical technique that allows complete and precise microscopic margin analysis by using horizontal frozen sections. The purpose of MMS is twofold: to ensure definitive excision and to minimize loss of normal surrounding tissue. MMS offers the advantages of superior cure rates and, because tissue removal is minimized, excellent cosmetic outcomes. Therefore, MMS has become the treatment of choice for many high-risk tumors. Because this technique is labor intensive, MMS is not indicated in certain situations. Understanding the indications, advantages, and disadvantages of MMS remains paramount for facial plastic surgeons managing NMSC.

Contemporary Mohs surgery applications

PURPOSE OF REVIEW

The incidence of cutaneous malignancies continues to rise and it is likely that the majority of skin cancers referred to otolaryngologists will have characteristics that necessitate a more complex and aggressive approach. Mohs micrographic surgery is a tissue-sparing technique that allows for excision of cancers under complete microscopic control and thus boasts high cure rates. This paper reviews the Mohs technique and discusses the current indications for Mohs surgery in the head and neck.

RECENT FINDINGS

For high-risk basal cell and squamous cell carcinomas, studies continue to report superior cure rates with Mohs surgery compared with non-Mohs modalities such as standard surgical excision. Despite several supporting studies, Mohs surgery for melanoma continues to be controversial in the literature, as histological identification of melanoma with frozen sections remains challenging despite advances. Other means of margin control remain popular among non-Mohs surgeons, including frozen section analysis and, more recently, photodynamic delineation.

SUMMARY

For cutaneous malignancies of the head and neck, Mohs surgery offers the distinct advantages of complete microscopic margin control coupled with tissue conservation and thus boasts of high cure rates. It is important for otolaryngologists to understand the technique and current indications for Mohs surgery.

La chirurgie micrographique de Mohs dans la prise en charge des carcinomes basocellulaires

AIMS

The goal of this work was to assess the validity of Mohs Micrographic Surgery (MMS) for basal cell carcinoma (BCC) in a routine clinical setting.

MATERIAL AND METHODS

Our adaptation of the technique described by Mohs and coll allows intraoperative histological examination of all surgical edges of the resection. Sixteen men and 4 women were selected.

RESULTS

Average operative time was 2 hours 30 minutes. No false results were noted. The cosmetetic and functional outcomes were good.

CONCLUSION

MMS is a safe and reproducible surgical technique made possible by solid team work. It is adapted for the treatment of BCC with a high risk of recurrence. The cosmetetic and functional results are quite satisfactory. The recurrence rate at 5 years is 10 times less than with other methods of treatment. The additional time required for this surgery be put in balance with the number of tumors for which a second intervention would have been necessary if conventional surgery had been used. All procedures were performed under local anesthesia, and none or the patients required a second intervention.

Mohs micrographic surgery in the treatment of lentigo maligna and melanoma

BACKGROUND AND OBJECTIVES

The treatment of lentigo maligna (LM) and lentigo maligna melanoma (LMM) is challenging due to lesion location, size, patient age, and potential for recurrence and spread. The largest studies to date confirm that for melanocytic tumours, MMS provides high local control rates while minimizing tissue loss. Herein we report our local control rate for melanoma treated by MMS over a decade.

METHODS

Charts were reviewed on all patients with melanocytic tumors treated by a single physician (JPA) using MMS over the time period of 1993-2002. Demographic, surgical and pathological details were recorded. Patients were followed for local, regional and distant recurrences.

RESULTS

The patient population was comprised of 199 patients with 202 melanomas. There were 69 invasive lesions, with a mean Breslow depth of 0.92 mm (0.2-3.6 mm). The mean number of levels required to clear the lesions was 2.7 (1-7), resulting in a mean defect size of 11.8 cm2 (0.9-70.7 cm2). Patients with LMM were significantly older (73.2 vs. 66.5 yrs, p = 0.012) and had larger defects after MMS (16.74 cm2 vs. 10.27 cm2) than patients with LM. At a mean follow-up of 29.8 months, there were no local recurrences, four regional recurrences, and two distant recurrences.

CONCLUSION

MMS is an effective modality for the clearance of melanocytic tumors.