Microcystic Adnexal Carcinoma: Report of Seven Cases Including One with Lung Metastasis

Distant Metastatic Microcystic Adnexal Carcinoma

Microcystic adnexal carcinoma (MAC) is a rare malignant neoplasm of ductal origin. MAC is a clinically aggressive, locally destructive tumor with a high rate of recurrence, but distant metastasis is rare. A 55-year-old male who had been taking immunosuppressants for 2 years after a liver transplantation due to hepatocellular carcinoma presented with a dermal nodule on the sole. He visited the clinic because the nodule, discovered 3 months ago, continued to increase in size. The histopathologic findings from the lesion were consistent with MAC. The patient underwent wide local excision and confirmed a histologically negative margin. After 11 months, the patient revisited with multiple skin nodules on the buttock, back, and right forearm that were distant from the primary tumor site. The lesions were histologically confirmed as MAC. We report a rare case of MAC with distant metastasis.

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.

Metastatic Basal Cell Carcinoma of the Skin: A Comprehensive Literature Review, Including Advances in Molecular Therapeutics

Basal cell carcinoma (BCC) of the skin is the most common type of malignant human tumor. In Europe, the incidence of BCC ranges from 44.6 to 128 cases per 100,000 inhabitants annually, whereas in the United States, the yearly incidence rate ranges between 500 and 1500. The global incidence has been calculated to be as high as 10 million cases of BCC per year. There are 2 main clinical patterns of BCC-the familial BCC in basal cell nevus syndrome and sporadic BCC. The etiology of cutaneous BCC is usually the result of the interaction between solar ultraviolet radiation and genetic factors. Somatic or germline mutations in the effector components of the hedgehog signaling pathway (ie, PTCH1, PTCH2, SMO or SUFU genes) are responsible for ∼90% of the cases of both sporadic and familial BCC, all causing a constitutive activation of the hedgehog pathway. Cutaneous BCC very rarely metastasizes, and diagnosis in metastatic sites can be very difficult. Metastatic BCC has weakly effective therapeutic options with a poor prognosis until few years ago. In 2012, small-molecule therapies, involving inactivation of the hedgehog signaling pathway, and capable of reducing tumor growth and progression have been introduced into clinical practice for advanced (locally advanced or metastatic) BCC. We performed a comprehensive literature review on metastatic BCC and found at least 915 cases reported to date. In addition, we extensively discussed the differential diagnosis of metastatic BCC, and outlined the advances in clinical therapeutics involving these small molecules.

Metastatic Cutaneous Basal Cell Carcinoma: Report of 2 Cases Preceding the Hedgehog Pathway Antagonists Era

Basal cell carcinoma (BCC) of the skin is the most common type of malignant human tumor. However, metastatic BCC is a very rare event with weakly effective therapeutic options and a poor prognosis, until a few years ago. In 2012, small-molecule therapies, capable of inactivating the hedgehog signaling pathway and thus reducing tumor growth and progression, were introduced into clinical practice for the treatment of patients with advanced BCC. We present retrospectively 2 personal cases of metastatic BCC of the skin, from the premolecular therapy era, from primary tumors that arose years before in the head and neck area. The former case occurred in a 45-year-old woman with a history of recurrent BCC of the retroauricular skin who eventually died due to diffuse metastatic spread. The latter case concerned a 70-year-old man also with a history of recurrent BCC of the nasal-perinasal skin who developed multiple subcutaneous and lymph node metastases in the neck. In both cases, the diagnoses were based on biopsies of the metastatic sites. The first patient died 5 months after the diagnosis of metastatic disease, while the second was alive and disease-free 2 years after neck lymph node dissection and external radiation therapy, and then lost to follow-up. We extensively discuss several tumor entities with basal or basaloid features that may enter the differential diagnosis with BCC in metastatic sites. In addition, we briefly summarize the advances in clinical therapeutics using small molecules, which are now an integral part of the treatment of such advanced BCC cases.

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.

Skin Adnexal Tumors in Plain Language: A Practical Approach for the General Surgical Pathologist

CONTEXT.—

Skin adnexal tumors, those neoplasms deriving from hair follicles and sweat glands, are often a source of confusion amongst even experienced pathologists. Many well-described entities have overlapping features, tumors are often only partially sampled, and many cases do not fit neatly into well-established classification schemes.

OBJECTIVES.—

To simplify categorization of adnexal tumors for the general surgical pathologist and to shed light on many of the diagnostic dilemmas commonly encountered in daily practice. The following review breaks adnexal neoplasms into 3 groups: sebaceous, sweat gland-derived, and follicular.

DATA SOURCES.—

Pathology reference texts and primary literature regarding adnexal tumors.

CONCLUSIONS.—

Review of the clinical and histopathologic features of primary cutaneous adnexal tumors, and the diagnostic dilemmas they create, will assist the general surgical pathologist in diagnosing these often challenging lesions.

Malignant adnexal tumors of the skin: a single institution experience

BACKGROUND

Malignant adnexal tumors of the skin (MATS) are rare. We aimed to measure the survival of patients with MATS and identify predictors of improved survival.

METHODS

A retrospective review of MATS treated at our institution from 1990 to 2012.

RESULTS

There were 50 patients within the time period. Median age was 59.5 years (range 22-95); primary site was the head and neck (52%); most common histologic subtypes were skin appendage carcinoma (20%) and eccrine adenocarcinoma (20%); and the vast majority were T1 (44%). Most patients (98%) underwent surgical treatment. Chemotherapy and radiation were administered to 8 and 14% of patients, respectively. Recurrence rate was 12%. Median OS was 158 months (95% CI, 52-255). OS and recurrence-free survival at 5 years were 62.4 and 47.4% and at 10 years 56.7 and 41.5%, respectively. Five-year and 10-year disease-specific survival (DSS) was 62.9%. Age > 60 years was an unfavorable predictor of OS (HR 12.9, P < .0008) and recurrence-free survival (RFS) (HR 12.53, P < .0003). Nodal metastasis was a negative predictor of RFS (HR 2.37, P < 0.04) and DSS (HR 7.2, P < 0.03) while treatment with chemotherapy was predictive of poor DSS (HR 14.21, P < 0.03).

CONCLUSIONS

Younger patients had better OS and RFS. Absence of nodal metastasis translated to better RFS and DSS. Lymph node basin staging is worth considering in the workup and treatment.

Histological Features and Treatment Approach of Trichoblastic Carcinomas: From a Case Report to a Review of the Literature

Background

Trichoblastic carcinoma (or malignant trichoblastoma) is a rare malignant cancer of adnexal structures with morphological features that in some cases are reminiscent of a trichoblastoma. Trichoblastic carcinoma is underdiagnosed as it is a rather recent entity which is still not recognized as such by all pathologists. The differential diagnosis with basal cell carcinoma is often difficult to make and the optimal treatment has not yet been established.

Case report

We report the case of a 43-year-old patient who underwent surgical excision and adjuvant radiotherapy for a growing mass of 40 × 48 mm located in the lumbar right paraspinal skin. The pathological findings demonstrated a trichoblastic carcinoma. The clinicopathological profile, the histogenesis, and the difficulties related to the histopathological diagnosis and treatment of this rare entity are discussed in this article.

Conclusion

Although the published reports on this disease are few, surgery should be considered the standard therapeutic approach for trichoblastic carcinomas. Selected cases presenting clinical features of local aggressiveness can safely be treated with adjuvant irradiation to improve local control. However, acute and particularly late toxicities need to be taken into account in the decision.

Adnexal Carcinomas Treated With Mohs Micrographic Surgery: A Comprehensive Review

BACKGROUND

Adnexal carcinomas (ACs) are rare cutaneous malignancies of sweat gland or pilosebaceous origin. Optimal treatment and metastatic potential of AC are poorly defined. Mohs micrographic surgery (MMS) has been increasingly used to treat AC.

OBJECTIVE

To review selected primary cutaneous AC and their treatment outcomes with MMS.

MATERIALS AND METHODS

Literature review using PubMed search for articles related to primary cutaneous ACs.

RESULTS

Sebaceous carcinoma treated with MMS recurred and metastasized in 6.4% and 3.7%, respectively. Primary cutaneous mucinous carcinoma treated with MMS recurred and metastasized in 9.6% and 6.4%, respectively. After MMS, 4.7% of microcystic AC recurred with no reported metastases. After MMS, recurrences and metastases of trichilemmal carcinoma or hidradenocarcinoma have not been reported. Two (4.2%) regional lymph node metastases but no distant metastases or local recurrences have been reported in eccrine porocarcinoma. Squamoid eccrine duct tumor, pilomatrix carcinoma, and spiradenocarcinoma treated with MMS are also reviewed.

CONCLUSION

The rarity of ACs and the lack of comparative data on treatment makes conclusive recommendations on treatment difficult. Recent large case series and reviews suggest MMS is a useful and possibly superior treatment for AC and should be considered if primary cutaneous disease is suspected.

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.

Update on Malignant Sweat Gland Tumors

Malignant sweat gland tumors are rare cutaneous neoplasms, traditionally separated according to their behavior into low- and high-grade malignant. There is significant morphologic overlap, and outright malignant tumors may show relatively bland histologic features. They may, therefore, be mistaken easily for benign neoplasms. Recognition of these tumors and accurate diagnosis is important for early treatment to prevent aggressive behavior and adverse outcome. This article provides an overview of 4 important entities with emphasis on diagnostic pitfalls, differential diagnosis and recent developments. Microcystic adnexal carcinoma, squamoid eccrine ductal carcinoma, aggressive digital papillary adenocarcinoma, and spiradenocarcinoma are discussed in detail.

Microcystic adnexal carcinoma in a non-Caucasian patient: A case report and review of the literature

Microcystic adnexal carcinoma (MAC) is extremely rare among Asians, with the majority of cases presenting in Caucasian individuals. The current study describes the case of a 38-year-old Chinese woman who presented with a 10 year history of a mass in the upper lip. A biopsy resulted in a diagnosis of MAC. The patient underwent complete surgical resection and the tumor was successfully excised. During 6 months of follow-up, there was no evidence of recurrence. To the best of our knowledge, the present case is the first Chinese case to be reported in the English literature, and is presented with the aim of increasing the awareness and aiding in the management of MAC in non-Caucasian populations.

Microcystic adnexal carcinoma: successful management of a large scalp lesion

Microcystic adnexal carcinoma (MAC) is a rare, malignant cutaneous neoplasm. It is important for us to become more aware of it, as it is often misdiagnosed, either clinically or histopathologically. We report a case of an extensive scalp lesion that was successfully treated using a combination of resection and adjuvant radiotherapy.

Unusual presentation of primary orbital microcystic adnexal carcinoma

Microcystic adnexal carcinoma (MAC) is a rare and locally aggressive malignancy that occurs on the face, can invade deep tissue, and can rarely invade the orbit via perineural spread. It has been reported most often in the form of a cutaneous lesion. Although there have been 3 prior case reports of an orbital presentation of MAC, all have been from undiagnosed cutaneous or subcutaneous lesions. We report a rare case of a primary orbital MAC in a 39-year-old healthy woman who presented with progressive diplopia and enophthalmos without evidence of any cutaneous or subcutaneous lesions.

Microcystic squamous cell carcinoma of the lung: a clinicopathologic study of three cases

Three cases of pulmonary squamous cell carcinoma (SCC) are described displaying a prominent microcystic pattern closely resembling microcystic adnexal carcinoma of the skin (MAC). The patients were 2 women and 1 man aged 72 to 83 years. Histologically, in addition to conventional SCC, all tumors showed striking microcystic changes characterized by nests and strands of basaloid squamous cells with central cystic spaces, peripheral palisading, and cytoplasmic clearing of the central tumor portions. Follow-up available for 2 patients revealed that 1 was alive at 76 months and 1 had died 38 months after diagnosis. Microcystic SCC is an unusual variant of SCC of the lung histologically mimicking tumors with glandular or adnexal differentiation and a particularly striking resemblance to MAC of the skin. The importance of the recognition of this growth pattern lies in the separation from other often less aggressive pulmonary neoplasms or metastatic disease from a cutaneous tumor.

Microcystic adnexal carcinoma: the first reported congenital case

Microcystic adenexal carcinoma is a rare, locally aggressive, malignant appendage tumor also known as sclerosing sweat duct carcinoma. Since widespread recognition of microcystic adenexal carcinoma as a distinct clinicopathologic entity, approximately 300 total cases have been reported in the literature, with only eight previous cases reported in children under the age of 18, with no reported cases in patients younger than 6 years old. Our patient is unique in that the lesion was present at birth, making this the youngest case of microcystic adenexal carcinoma reported.

Malignant skin neoplasms

Skin cancers may be derived from any part of the skin, and the classification of all variants is extensive. Overall they are the most common cancers of the body, and include those that are highly mortal and those that are associated with an increased morbidity. In this review the most common skin cancers confronted by the clinician and their management are discussed. New associations are highlighted, as well as new information that can help the clinician to better understand the pathogenesis of many of these entities.

Sclerosing sweat duct carcinoma in a 6-year-old African American child

Sclerosing sweat duct carcinoma is a rare, locally aggressive adnexal tumor that frequently occurs on the face of middle-aged adults, invades deeply, and has a propensity to recur. We report a rare instance of sclerosing sweat duct carcinoma occurring in a 6-year-old African American child and review the literature of this infrequently observed neoplasm.

Low-dose X-ray depilatory treatment induces trichoblastic tumors of the scalp

BACKGROUND

Depilatory radiotherapy for ringworm was largely used before antifungals were available. Patients who underwent this treatment are at high risk of developing scalp tumors or other cancers. The aim of this study was to characterize scalp tumors occurring after X-ray therapy for ringworm.

METHODS

We included cases of postradiotherapy scalp tumors recorded at the Dermatology Department of the Charles Nicolle Hospital, Tunis between 1988 and 2001. We recorded clinical descriptions and all cases were resubmitted to microscopic analysis.

RESULTS

Sixty-one tumors occurred in 33 men and 12 women with a mean age of 49.8 years. Radiodermatitis was present in 21% of patients. Tumors were basal cell carcinomas in 47 cases, trichoblastomas in 10 cases and trichoblastic carcinomas in 4 cases. Twelve patients had 2-5 tumors, with combinations of tumor types in 3 of them. Mean delay of onset of tumors after radiotherapy was 39.4 years in basal cell carcinoma cases, 38.3 years in trichoblastoma cases and 35.6 years in trichoblastic carcinoma cases.

CONCLUSIONS

This series shows that although basal cell carcinoma is the most frequent tumor in this situation, trichoblastomas are common. We describe, for the first time, radio-induced trichoblastic carcinomas. Trichoblastic tumors have not yet been described in this context because this concept is relatively recent.

Dermoscopic and Reflectance Confocal Microscope Findings of Trichoepithelioma

BACKGROUND

Trichoepitheliomas (TE) are benign neoplasms of follicular differentiation. Solitary lesions are often confused with basal cell carcinoma (BCC). Reflectance confocal microscopy (RCM) and dermoscopy are imaging tools for in vivo, noninvasive evaluation of skin lesions. To date, there has been no description of their findings in the evaluation of TE.

OBJECTIVE

Our aim is to describe the dermoscopic and RCM findings of histopathologically confirmed TE.

METHODS

Four TE were evaluated, 2 each of the desmoplastic and nondesmoplastic variants. RCM was performed on 1 of the desmoplastic and both of the nondesmoplastic lesions.

RESULTS

Dermoscopically, all of the lesions showed arborizing telangiectasias. The desmoplastic lesions also had an ivory-white background throughout. RCM showed oval, darker-appearing tumor islands that contained brightly refractile material, consistent with keratin horn cysts at the center, as well as parallel bundles of highly refractile dermal collagen surrounding the tumor islands.

CONCLUSION

The ivory-white background throughout the lesion seen on dermoscopy may be helpful in distinguishing desmoplastic TE from BCC. The RCM findings in TE of keratin-filled cysts in tumor islands and attachment of the tumor to follicular structures have not been previously observed in BCC, and thus may also be diagnostically helpful. Further study is necessary for validation of these findings.