Microcystic Adnexal Carcinoma

Review on the Role of Paraffin-embedded Margin-controlled Mohs Micrographic Surgery to Treat Skin Tumors

Paraffin-embedded margin-controlled Mohs micrographic surgery (PMMS) includes various procedures such as slow Mohs or deferred Mohs technique, the Muffin and Tübingen techniques, and staged margin excision, or the spaghetti technique. PMMS is a variation of conventional Mohs micrographic surgery (MMS) that allows histopathological examination with delayed margin control. PMMS requires minimum training and may be adopted by any hospital. The setback is that PMMS can require procedures across multiple days. PMMS lowers the rate of recurrence of basal cell carcinoma vs wide local excision in high-risk basal cell carcinoma, and improves the rates of recurrence and survival in lentigo maligna. PMMS can be very useful in high-risk squamous cell carcinoma treatment. Finally, it is a promising technique to treat infrequent skin neoplasms, such as dermatofibrosarcoma protuberans, or extramammary Paget's disease, among others. In this article, we present a literature narrative review on PMMS, describing techniques and indications, and highlighting long-term outcomes.

Review on the Role of Paraffin-embedded Margin-controlled Mohs Micrographic Surgery to Treat Skin Tumors

Paraffin-embedded margin-controlled Mohs micrographic surgery (PMMS) includes various procedures such as slow Mohs or deferred Mohs technique, the Muffin and Tübingen techniques, and staged margin excision, or the spaghetti technique. PMMS is a variation of conventional Mohs micrographic surgery (MMS) that allows histopathological examination with delayed margin control. PMMS requires minimum training and may be adopted by any hospital. The setback is that PMMS can require procedures across multiple days. PMMS lowers the rate of recurrence of basal cell carcinoma vs wide local excision in high-risk basal cell carcinoma, and improves the rates of recurrence and survival in lentigo maligna. PMMS can be very useful in high-risk squamous cell carcinoma treatment. Finally, it is a promising technique to treat infrequent skin neoplasms, such as dermatofibrosarcoma protuberans, or extramammary Paget's disease, among others. In this article, we present a literature narrative review on PMMS, describing techniques and indications, and highlighting long-term outcomes.

Periocular Microcystic Adnexal Carcinoma: A Case Report and a Major Review

PURPOSE

To describe a patient with periocular microcystic adnexal carcinoma (MAC) and to review the clinical presentation, systemic work-up, histopathologic features, and outcome of all previously reported periocular MAC.

METHODS

A major literature review. PubMed/MEDLINE and Google Scholar databases were searched for all well-documented cases of periocular MAC.

RESULTS

The final analysis yielded 93 patients with MAC, 48 (52%) females, 39 (42%) males, and 6 with sex not specified (6%) with an average age of 56 years (range 3 days-95 years). Most tumors were localized to the eyebrow (26/93, 28%) and lower eyelid (20/93, 22%). Of patients with known information, MAC most commonly presented as a nodule (37/68, 54%) or plaque (20/68, 29%) with poorly-defined margins (20/51, 39%) and distortion of eyelid margin (13/51, 25%). Orbital involvement at any point of the disease course was seen in 20 of 93 (22%) patients. An accurate histopathologic diagnosis on initial biopsy was made in 25 of 70 (36%) cases. Initial management included surgical excision (47/93, 51%), Mohs micrographic surgery (17/93, 18%), and excision with frozen section control of margins (8/93, 9%). Aggressive or recurrent MAC was managed with multimodal therapies, including adjuvant radiation (10/34, 29%). The average follow-up after the last treatment was 3 years (median 2, range 0.2-20 years). In total, 33 of 86 (38%) tumors recurred, and 6 of 87 (7%) metastasized. Disease-related mortality occurred in 3 of 79 (4%) of patients.

CONCLUSIONS

Periocular MAC is frequently misdiagnosed on initial biopsy and has a tendency for recurrence and locally aggressive behavior, highlighting the importance of accurate timely diagnosis, and appropriate management.

Microcystic adnexal carcinoma of the eyelid and orbit: A case report and review of literature

Microcystic adnexal carcinoma (MAC), a rare and low-grade malignant skin tumor, is characterized by a high rate of misdiagnosis and a preponderance for local recurrence, but seldom seen nodal or distant metastasis. Although MAC typically occurs almost in the head and neck region, primary eyelid or orbital MAC is very rare. To explore the unique characteristics of the eyelid and orbital MAC, we reviewed the relevant literature. Based on its distinctive anatomical location and the aggressive behavior, eyelid or orbital MAC not only exhibit a high rate of misdiagnosis and local recurrence, but also lead to serious complications such as disfigurement after orbital exenteration, paranasal sinuses or intracranial invasion, even death. Misdiagnosis of MAC commonly result from its rarity and nonspecific clinical and histopathological presentation. To reduce or avoid misdiagnosis, it is important to increase awareness for MAC and obtain a full-thickness biopsy specimen in histopathological analysis. Due to its extensive invasive growth pattern, MAC has a high rate of local recurrence, so complete excision with clear margins and long-term follow-up of patients with MAC are necessary. About those serious complications of the eyelid and orbital MAC, early and accurate diagnosis, complete excision is very important. Moreover, an interprofessional team consisting of ophthalmologist, otolaryngologist, neurologist, dermatologist, pathologist, radiologist is needed to evaluate and treat this disease. In summary, increasing awareness, early and accurate diagnosis, complete excision, long-term follow-up, and a multidisciplinary team is crucial for management of the eyelid and orbital MAC.

Multifocal Recurrent Microcystic Adnexal Carcinoma

Microcystic adnexal carcinoma (MAC) is a rare and locally aggressive neoplasm with preponderance for local recurrence but rarely nodal or distant metastasis. A 38-year-old male was referred to our clinic for definitive treatment of known recurrent and concern for multifocal MAC from previous biopsy. The patient was treated with modified Mohs and reconstruction with an anterolateral thigh (ALT) free flap for tissue coverage. This case highlights the rare nature of multifocal MAC, treatment challenges of Mohs clearance versus wide local excision, and reconstructive challenge associated with large post treatment defects.

Desmoplastic Trichoepithelioma: Histopathologic and Immunohistochemical Criteria for Differentiation of a Rare Benign Hair Follicle Tumor From Other Cutaneous Adnexal Tumors

Desmoplastic trichoepitheliomas (DTEs) are benign cutaneous neoplasms that originate from the hair follicle and exhibit a preference for the facial region. This type of neoplasm is characterized by accelerated growth, with vigorous histologic and immunohistochemical features that may be confused with other skin cancers. Thus, the objective of this study is to establish a definitive diagnosis that can be widely used. This review was systematically carried out and includes case series and studies to establish valuable data that can be used for research. The articles were sought in PubMed, MEDLINE, and Google Scholar using the keywords "desmoplastic trichoepithelioma," "morphea basal cell carcinoma," "microcystic adnexal carcinoma," "syringoma," and "cutaneous breast carcinoma." From a total of 65 journal articles, we chose 42 studies describing the clinical features, etiology, histopathology, and immunohistochemical characteristics of tumors. After quality assessment, 10 studies were selected, representing the differentiating features among the four mentioned cutaneous tumors. The differential diagnosis of DTE also includes other cutaneous and follicular tumors. At present, there is no standardized grading system for trichogenic tumors, although several symptomatic terms have been offered. More recently, immunohistochemistry and histopathological studies support the differentiation between the above-mentioned cutaneous tumors. However, additional research needs to be conducted to obtain complete information regarding the specific distinct traits of the indicated cutaneous tumors.

State of the art of Mohs surgery for rare cutaneous tumors in the Spanish Registry of Mohs Surgery (REGESMOHS)

BACKGROUND

The use of Mohs micrographic surgery (MMS) for rare cutaneous tumors is poorly defined. We aim to describe the demographics, tumor presentation and topography, surgery characteristics and complications of MMS for rare cutaneous tumors in a national registry.

METHODS

Prospective cohort study of patients treated with MMS in Spain between July 2013 and June 2018. The inclusion criteria were patients with cutaneous tumors with final diagnosis different from basal cell carcinoma, squamous cell carcinoma, dermatofibrosarcoma protuberans, or any kind of melanoma.

RESULTS

Five thousand and ninety patients were recorded in the registry, from which only 73 tumors (1.4%) fulfilled the inclusion criteria: atypical fibroxanthoma (18), microcystic adnexal carcinoma (10), extramammary Paget's disease (7), Merkel cell carcinoma (5), dermatofibroma (4), trichilemmal carcinoma (4), desmoplastic trichoepithelioma (4), sebaceous carcinoma (3), leiomyosarcoma (2), porocarcinoma (2), angiosarcoma (2), trichoblastoma (1), superficial acral fibromyxoma (1), and others (10). No intra-surgery morbidity was registered. Postsurgery complications appeared in six patients (9%) and were considered mild. Median follow-up time was 0.9 years during which three Merkel cell carcinomas, one angiosarcoma, one microcystic adnexal carcinoma, and four others recurred (12.3%).

CONCLUSION

This national registry shows that rare cutaneous tumors represent a negligible part of the total MMS performed in our country with a low complication rate.

Evidence-Based Clinical Practice Guidelines for Microcystic Adnexal Carcinoma: Informed by a Systematic Review

IMPORTANCE

Microcystic adnexal carcinoma (MAC) occurs primarily in older adults of white race/ethnicity on sun-exposed skin of the head and neck. There are no formal guiding principles based on expert review of the evidence to assist clinicians in providing the highest-quality care for patients.

OBJECTIVE

To develop recommendations for the care of adults with MAC.

EVIDENCE REVIEW

A systematic review of the literature (1990 to June 2018) was performed using MEDLINE, Embase, Web of Science, and the Cochrane Library. The keywords searched were microcystic adnexal carcinoma, sclerosing sweat gland carcinoma, sclerosing sweat duct carcinoma, syringomatous carcinoma, malignant syringoma, sweat gland carcinoma with syringomatous features, locally aggressive adnexal carcinoma, and combined adnexal tumor. A multidisciplinary expert committee critically evaluated the literature to create recommendations for clinical practice. Statistical analysis was used to estimate optimal surgical margins.

FINDINGS

In total, 55 studies met our inclusion criteria. The mean age of 1968 patients across the studies was 61.8 years; 54.1% were women. Recommendations were generated for diagnosis, treatment, and follow-up of MAC. There are 5 key findings of the expert committee based on the available evidence: (1) A suspect skin lesion requires a deep biopsy that includes subcutis. (2) MAC confined to the skin is best treated by surgery that examines the surrounding and deep edges of the tissue removed (Mohs micrographic surgery or complete circumferential peripheral and deep margin assessment). (3) Radiotherapy can be considered as an adjuvant for MAC at high risk for recurrence, surgically unresectable tumors, or patients who cannot have surgery for medical reasons. (4) Patients should be seen by a physician familiar with MAC every 6 to 12 months for the first 5 years after treatment. Patient education on photoprotection, periodic skin self-examination, postoperative healing, and the possible normal changes in local sensation (eg, initial hyperalgesia) should be considered. (5) There is limited evidence to guide the treatment of metastasis in MAC due to its rarity. Limitations of our findings are that the medical literature on MAC comprises only retrospective reviews and descriptions of individual patients and there are no controlled studies to guide management.

CONCLUSIONS AND RELEVANCE

The presented clinical practice guidelines provide an outline for the diagnosis and management of MAC. Future efforts using multi-institutional registries may improve our understanding of the natural history of the disease in patients with lymph node or nerve involvement, the role of radiotherapy, and the treatment of metastatic MAC with drug therapy.

Microcystic Adnexal Carcinoma: A Review of the Literature

BACKGROUND

Microcystic adnexal carcinoma (MAC) is a rare, locally aggressive cutaneous neoplasm that commonly occurs on the face.

OBJECTIVE

The purpose of this article is to comprehensively review the current literature on MAC pertaining to epidemiology, pathogenesis, clinical presentation, histology, immunohistochemistry, prognosis, follow-up, and treatment.

MATERIALS AND METHODS

An extensive literature review was conducted using OVID MEDLINE and PubMed to identify articles relating to MAC.

RESULTS

Microcystic adnexal carcinoma typically presents as a skin-colored nodule on the face. The pathogenesis is mostly related to pilar and eccrine differentiation. Histologically, MAC can mimic syringoma, desmoplastic trichoepithelioma, and infiltrative basal cell carcinoma. Diagnosis is challenging because superficial shave biopsies may reveal only benign findings that do not warrant further management. A deep biopsy is mandatory for the correct diagnosis, and Mohs micrographic surgery provides the highest cure rate.

CONCLUSION

Microcystic adnexal carcinoma is a locally aggressive disease with histological margins that often far surpass what is clinically suspected. Mohs micrographic surgery is the standard of care for removal of these lesions. Patients with a history of MAC should be examined at least every 6 months for recurrence, metastasis, and development of additional skin cancers.

Treatments for microcystic adnexal carcinoma--A review

INTRODUCTION

Microcystic adnexal carcinoma (MAC) is a rare malignant cutaneous neoplasm presenting as a slow-growing, indurated nodule, papule or plaque. Clinically, the lesion can blend into the surrounding skin, obscuring borders and consequently delaying diagnosis histologically. Surgical and histologic techniques that emphasize examination of all margins may optimize management through early diagnosis and prevention of recurrences.

OBJECTIVE

This review aims to assess the current surgical and histology techniques that result in lower rates of tumor recurrence and, consequently, better clinical outcomes.

METHODS

A literature search of the PubMed database was conducted to identify studies examining wide local excision (WLE), Mohs micrographic surgery (MMS), radiotherapy (RT) and chemotherapy in the treatment of MAC.

RESULTS

WLE had a high likelihood of positive margins and local recurrence. MMS was found to have the lowest recurrence rates. Definitive RT could be considered for elderly patients or those who are poor surgical candidates, as large surgical defects may be required to obtain free margins with either WLE or MMS. Chemotherapy was found to be ineffective.

CONCLUSION

Complete margin evaluation with MMS permits complete tumor removal with subsequently low recurrence rate.

Mohs micrographic surgery of the eyelid: an overview of anatomy, pathophysiology, and reconstruction options

BACKGROUND

Mohs micrographic surgery (MMS) is the ideal treatment for skin cancer removal. The advantages of MMS in the eyelid area include its high cure rate, tissue-sparing effects, and overall cost effectiveness.

OBJECTIVE

To review eyelid anatomy, detail ocular tumors that are amenable to MMS, and examine the surgical repair options commonly used in this area.

MATERIALS AND METHODS

A review of the literature on MMS of the eyelid was performed with specific reference to ocular anatomy, eyelid malignancy types, and surgical reconstruction.

CONCLUSION

Eyelid function is critical for the maintenance of ocular health and vision. MMS is an ideal skin cancer treatment for the delicate structure of the eyelid, where maximal tissue preservation is critical. There are a plethora of reconstruction options to consider after MMS has been performed in this area. The choice of repair and surgical outcome depend, in part, on the surgeon's knowledge of eyelid anatomy and his or her ability to assess the repair requirements of the post-MMS defect. Dermatologic surgeons can effectively work with other specialists to help ensure that their patients receive a cure with restored ocular function and optimal cosmesis.

Periocular cutaneous malignancies: a review of the literature

BACKGROUND

The periocular skin is susceptible to numerous benign and malignant neoplasms. Periocular malignancies may present differently, behave more aggressively, and pose greater challenges for treatment and repair than malignancies at other cutaneous sites. Between 5% and 10% of cutaneous malignancies occur periorbitally, with basal cell carcinoma reported as the most common malignant periocular tumor, followed by squamous cell carcinoma, sebaceous gland carcinoma, cutaneous melanoma, Merkel cell carcinoma, and other rare tumors.

OBJECTIVE

To review the current literature on cutaneous malignancies of the periocular region pertaining to etiology, incidence, clinical presentation, differential diagnosis, complications, and treatment options.

MATERIALS AND METHODS

An extensive literature review was conducted using PubMed, searching for articles on periocular and periorbital cutaneous malignancies.

CONCLUSIONS

Timely diagnosis and management of periocular malignancies is essential because of their proximity to and potential to invade vital structures such as the orbit, sinuses, and brain. Surgical excision remains the standard of care for the majority of periorbital malignancies, but given the sensitive anatomic location, tissue-sparing techniques with margin control such as Mohs micrographic surgery are the preferred method for most nonmelanoma skin cancers. Depending on tumor type, other treatment modalities may include radiation, chemotherapy, cryosurgery, topical medications, and photodynamic therapy.

Mohs micrographic surgery in the treatment of microcystic adnexal carcinoma

Microcystic adnexal carcinoma is a rare neoplasm with a propensity for slow growth and extensive local invasion. Pathology is characterized by multiple islands of basaloid epithelial cells, ductal structures, and keratinizing cysts, located intradermally but often extending deep as thin strands of tumor cells intercalating between collagen bundles. Perineural and intramuscular invasion are common. Treatment with Mohs surgery allows for fewer procedures with increased likelihood of long-term cure and tissue conservation.