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.

Mohs micrographic surgery for the treatment of primary cutaneous mucinous carcinoma.

Primary cutaneous mucinous carcinoma (PCMC) is a rare adnexal tumour of the skin. Clinically, it appears as a benign cyst, but it has characteristic histopathology. It is a slow-growing tumour that rarely metastasizes but is associated with significant morbidity due to its high recurrence rate. Standard practice has been to surgically remove it with a wide local excision of 1-2-cm margin. In the last decade, increasing reports of Mohs micrographic surgery (MMS) for the treatment of PCMC have been described. MMS appears to reduce recurrence rates while allowing for more conservative margins. Given the rarity of PCMC, there are no prospective randomized control trials on treatment. This is the largest case series of PCMC treated by MMS to date.

Improved Margin Control of Microcystic Adnexal Carcinoma After Mohs Micrographic Surgery Compared With Wide Local Excision.

BACKGROUND: Microcystic adnexal carcinoma (MAC) is a locally aggressive and deeply infiltrative cutaneous tumor primarily treated with excision; however, there are limited data comparing outcomes by surgical approach. OBJECTIVE: To compare surgical outcomes of MAC treated with Mohs micrographic surgery (MMS) and wide local excision (WLE). METHODS: A 27-year retrospective cohort study of primary MAC was performed. Surgical (i.e. margin status after resection) and recurrence outcomes (including local recurrence [LR], nodal metastases [NM], and distance metastases [DM]) were analyzed by type of surgical approach (MMS and WLE). RESULTS: Sixty-nine MACs were included, of which 34 (49.3%) were treated with MMS and 35 (50.7%) with WLE. All MMS-treated tumors had negative margins after the first surgery attempt. Twenty-one (60.0%) tumors treated with WLE had positive margins after the first surgical attempt and required additional procedures. More tumors treated with WLE developed LR, NM, or DM, although this did not meet statistical significance. LIMITATIONS: Retrospective single institution study. CONCLUSION: Greater than half of MAC tumors treated with WLE had positive margins after the initial surgery and required multiple procedures for complete removal. Real-time complete margin assessment is important for this locally aggressive and infiltrative tumor.

A diagnostic challenge in an atypical variant of microcystic adnexal carcinoma mimicking ulcerative basal cell carcinoma: a case report and brief literature review.

Microcystic adnexal carcinoma (MAC) is a rare adnexal tumor with eccrine and pillar differentiations with a localized and aggressive nature, often misdiagnosed as other dermatoses. The most common clinical manifestations of MAC are yellowish or skin-colored papules, nodules, and plaques. However, in some rare cases an atypical manifestation such as ulceration that resembles malignancies such as basal cell carcinoma (BCC) can also occur. Diagnosis of MAC mainly relies on the aid of histopathology. Due to potential infiltration to other structures such as in perineural invasion, wide surgical excision or Mohs micrographic surgery is the preferred surgical option. We report the case of a 75-year-old male patient with ulcerative lesion on the forehead that clinically resembled BCC in addition to typical dermoscopic findings of BCC. However, histopathology confirmed a diagnosis of MAC, prompting physicians to be more aware of this condition when encountering chronic ulcerative lesions. After wide excision and a 1-year follow-up, the patient exhibited no signs of recurrences and will continue long-term follow-up.

Malignant Cutaneous Adnexal Tumors and Role of SLNB.

BACKGROUND: Malignant cutaneous adnexal tumors (MCATs) are rare and their natural history is poorly understood. Available literature indicates aggressive behavior with a significant risk of metastasis. STUDY DESIGN: Retrospective review of our institutional surgical oncology databases was performed for patients diagnosed with MCATs (2001-2020). We hypothesized that most patients have a low risk of lymph node involvement, recurrence, and death. Kaplan-Meier statistical analysis was used to assess risk of recurrence and 5-year survival. RESULTS: We identified 41 patients diagnosed with MCATs (median age 59 years, 68% were men). Most patients had long-standing cutaneous lesions (median 24 months) and no palpable adenopathy. Most patients had stage I or II disease (98%). Primary tumors were treated with wide local excision (n = 28 [68%]), Mohs surgery (n = 5 [12%]), or amputation (n = 8 [19%]). Of 25 patients who underwent SLNB (61%), 1 had lymphatic metastasis. These include apocrine carcinoma (1 of 3), digital papillary adenocarcinoma (0 of 8), porocarcinoma (0 of 4), and additional MCAT sub-types (0 of 10). Three patients (7%) had disease recurrence at a median interval of 3.6 years (interquartile range 1.5 to 4.4 years). Five patients (12%) died at a median interval of 7 years (interquartile range 6.7 to 9.2 years), but only 1 patient was known to have succumbed to MCAT. Overall 5-year survival rate was 96% (95% CI, 75% to 99%). CONCLUSIONS: Despite the historical impression that MCATs have a high metastatic potential, most patients have low recurrence rates and excellent 5-year survival rates. Lymphatic disease identified after SLNB in early-stage tumors is rare and the value of this staging procedure in MCAT remains unclear.

Proliferating trichilemmal tumour of the eyelid in a 7-year-old girl.

Proliferating trichilemmal tumours (PTTs) are rare cutaneous adnexal tumours derived from the hair shaft outer root sheath. We are reporting the first case of PTT in a young child. In this case, a 7-year-old girl presented with trichilemmal keratinisation consistent with PTT. The patient was monitored with no signs of recurrence. PTT is a rare tumour occurring primarily in adults and we present this case so that young patients with PTT can be diagnosed and treated appropriately with a painless, mobile, rapidly growing mass on the right upper eyelid. CT imaging showed well-circumscribed, heterogenous mass measuring 1.6 cm with fluid-filled appearance and no tissue invasion. Surgical excision was performed and pathology revealed an unencapsulated, well-demarcated tumour.

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.

[Eccrine carcinoma: a diagnostic pitfall]. / Het eccrien carcinoom, een diagnostische valkuil.

BACKGROUND: The eccrine carcinoma is a rare form of skin adnexal malignancy, usually presenting as a locally invasive, solitary lesion in the head and neck region. Histopathologically and immunohistochemically, eccrine carcinomas are difficult to differentiate from cutaneous metastases of breast carcinomas. Unlike treatment of cutaneous metastasis, treatment of a solitary eccrine carcinoma entails excision, generally without systematic therapy. CASE DESCRIPTION: A seventy-year-old woman previously treated definitively for (in situ) breast cancer, undergoes excision of a nodule on the scalp. The histopathology report indicates a lesion typical for cutaneous metastasis of breast carcinoma. However, diagnostic imaging excludes recurrent breast cancer or metastatic spread. When subsequent clonality testing with archived breast cancer tissue from the earlier episode does not show a relation, the pathologist defines the lesion as an eccrine carcinoma. A re-excision is conducted, which does not show any residual tumorous tissue, and at follow-up there are no signs of recurrence or metastases. CONCLUSION: As a relatively rare and unknown malignancy, with strong histopathological resemblance to cutaneous metastasis of breast carcinoma, eccrine carcinoma poses a diagnostic challenge to both clinicians and pathologists.

Solid Microcystic Adnexal Carcinoma on the Thigh: An Unusual Location.

Solid carcinoma, probably the solid variant of microcystic adnexal carcinoma, is an apocrine adnexal tumor first described in 1998. The authors report an additional new case of the tumor at an unusual localization. A 78-year-old man presented with an asymptomatic firm plaque on his right thigh that had been present for 15 years. A biopsy was taken, and then, the lesion was removed. A pathological study showed a huge number of islands made up of aggregations of neoplastic epithelial cells. The epithelial islands showed variable sizes and shapes at scanning magnification, arranged columns, cords, and strands at the basis of the tumor. The neoplastic cells were embedded within a fibrotic stroma. Ductal differentiation, cystic structures, and neurotropism were also observed. Immunohistochemically, the neoplastic cells expressed high-molecular-weight keratin (cytokeratin 5/6), broad-spectrum keratin (AE1/AE3), p40, and p63. No immunoreactivity was found for BerEP4, cytokeratin 7, cytokeratin 19, cytokeratin 20, chromogranin A, carcinoembryonic antigen, and S-100. The lesion was completely removed with slow-Mohs micrographic surgery. Two stages and previous debulking were necessary to obtain free margins. The second stage included the muscular fascia. The patient remains free of tumor after a year of follow-up. Solid microcystic adnexal carcinoma is a rare skin tumor that seems to occur more frequently in the scalp than in the face, but no area of the body can be excluded, as reported in our case. Differential diagnosis should include sclerosing and clear-cell basal cell carcinoma, clear-cell dermal duct tumor, or desmoplastic trichoepithelioma. Mohs micrographic surgery is the treatment of choice.

Approaches to Perineural, Lymphovascular, and Single-Cell Disease.

BACKGROUND: Mohs micrographic surgeons should be adept in identifying and managing perineural invasion (PNI), lymphovascular invasion (LVI), and single-cell spread (SCS), features denoting high-risk behavior of basal cell carcinoma (BCC), cutaneous squamous cell carcinoma (cSCC) and microcystic adnexal carcinoma (MAC). OBJECTIVE: The purpose of this article is to review the literature and guidelines regarding the diagnosis of PNI, LVI, and SCS in BCC, cSCC, and MAC and examine the role of advanced diagnostic studies, adjuvant therapy, and reconstructive techniques of these high-risk tumors. MATERIALS AND METHODS: We performed a literature search including the following terms: PNI, LVI, SCS, BCC, cSCC, keratinocyte carcinoma, MAC, sentinel lymph node biopsy, radiation, chemotherapy, and staging. Relevant studies, case reports, and review articles were included, as well as National Comprehensive Cancer Network guidelines. RESULTS: Pancytokeratin immunohistochemistry may aid in the diagnosis of high-risk features of BCC and cSCC. Reconstruction of the Mohs defect should be carefully considered to allow for thorough inspection. Radiation therapy should be considered as an adjuvant treatment option for high-risk cSCC and BCC. Close surveillance for recurrence is warranted. CONCLUSION: The Mohs surgeon should be competent in identification of high-risk tumors and to understand how best to manage, further treat, and follow these tumors.

Microcystic Adnexal Carcinoma: A Rare, Commonly Misdiagnosed Malignancy.

Microcystic adnexal carcinoma (MAC) is a rare, malignant cutaneous neoplasm that often presents as an inconspicuous, benign appearing lesion. Patients most commonly are asymptomatic and present for improved cosmesis, however perineural invasion may result in local numbness, paresthesia or pruritus. Although distant metastasis is rare, MAC has an increased propensity for local invasion, often resulting in significant morbidity as late presentation and misdiagnosis are common. A high index of suspicion is imperative, and deep tissue biopsy with defining histologic characteristics is required for diagnosis. Mohs micrographic surgery is currently the standard of care, providing the highest possibility for long-term cure. We present a case report of a 43-year-old male Air Force U-2 pilot with a benign presentation and initial clinical misdiagnoses of MAC, who underwent Mohs micrographic surgery followed by cervicofacial flap reconstruction of a 5.5 × 3.5 cm defect. We also identify increased radiation exposure of U-2 pilots as a potential risk factor for the early development of MAC, emphasizing the importance of exploring patient risk factors while having a high index of suspicion to aid in early diagnosis.

Tratamiento de las neoplasias anexiales cutáneas malignas / Treatment of Malignant Cutaneous Adnexal Neoplasms

Las neoplasias anexiales cutáneas malignas constituyen un grupo de carcinomas poco frecuentes, habitualmente de bajo grado de malignidad, que muestran diferenciación folicular, sebácea, apocrina o ecrina o una combinación de las 3 primeras. Clínicamente suelen ser neoplasias con características poco distintivas, siendo necesaria una biopsia que permitirá establecer el tipo de diferenciación y el diagnóstico definitivo. Al tratarse de una enfermedad poco frecuente, no existe un claro consenso sobre el tratamiento más eficaz. En la mayoría de casos se considera la microcirugía de Mohs como la opción más efectiva para prevenir recidivas. La radioterapia y quimioterapia han sido escasamente estudiadas y solo se han mostrado eficaces en escasas ocasiones

Malignant cutaneous adnexal neoplasms form a group of rare, typically low-grade-malignancy carcinomas with follicular, sebaceous, apocrine, or eccrine differentiation or a combination of the first 3 subtypes. Their clinical presentation is usually unremarkable, and biopsy is required to establish the differentiation subtype and the definitive diagnosis. Due to their rarity, no clear consensus has been reached on which treatment is most effective. Mohs micrographic surgery is considered to be the best option to prevent recurrence in the majority of patients. Radiotherapy and chemotherapy have been studied in very few cases and have rarely been shown to be effective

Surgery and Adjuvant Radiation for High-risk Skin Adnexal Carcinoma of the Head and Neck.

OBJECTIVES: Skin adnexal carcinoma (SAC) is a rare cutaneous malignancy that arises from sebaceous and sweat glands. These carcinomas are believed to behave more aggressively than cutaneous squamous cell carcinomas (SCC) with a propensity for local recurrence. The role of adjuvant radiotherapy in SAC is undefined. METHODS: We retrospectively reviewed all cases of head and neck SAC treated with surgery and adjuvant radiation from 2000 to 2012 at a single institution. RESULTS: Nine cases were identified. Median age was 67 (range, 52 to 88) years. The histologies were: adnexal carcinoma (n=1), adnexal carcinoma with sebaceous differentiation (n=1), adnexal carcinoma with squamous differentiation (n=1), skin appendage carcinoma (n=1), sclerosing sweat duct carcinoma (n=1), mucinous carcinoma (n=1), ductal eccrine adenocarcinoma (n=1), porocarcinoma (n=1), and trichilemmal carcinoma (n=1). All tumors were reviewed by a dermatopathologist to confirm the SAC diagnosis.All patients had undergone surgery. Indications for adjuvant radiation included involved lymph nodes (n=4), perineural invasion (n=2), nodal extracapsular extension (n=2), positive margin (n=1), high-grade histology (n=6), multifocal disease (n=2), and/or recurrent disease (n=5). Radiation was delivered to the primary site alone (n=3), to the draining lymphatics alone (n=2), or to both (n=4). One patient received concurrent cisplatin. Median dose to the primary site was 60 Gy and to the neck was 50 Gy.Median follow-up was 4.0 years (range, 0.6 to 11.4 y). Locoregional control was 100%. Five-year progression-free survival was 89%. There was 1 acute grade 3 toxicity and no greater than or equal to grade 2 late toxicities were recorded. CONCLUSIONS: Surgery and adjuvant radiation for high-risk SAC offers excellent locoregional control with acceptable toxicity.

A Case of Trichogerminoma With Pilomatrical Differentiation and a Unique Immunohistochemical Profile.

Trichogerminomas are rare adnexal neoplasms first described by Sau et al in 1992. Including the initial report, 20 cases have been reported, all with similar histological features, namely tumor nodules composed of basaloid cells that form densely packed, round nests or "cell balls" and which demonstrate variable degrees of pilosebaceous differentiation. In this study, the authors report a case of a trichogerminoma with pilomatrical differentiation and a unique immunohistochemical profile. The patient is a 71-year-old man with a well-delineated nodule on the top of the scalp. Histologically, the lesion measured 16 mm in greatest dimension and was composed of nodules of basaloid cells with central, compact, slightly eosinophilic cells nests. Immunohistochemically, the tumor nodules diffusely expressed cytokeratins 34ßE12, AE1/3, and CK5/6. Diffuse expression of ß-catenin and nuclear expression of p63 were also evident. The peripheral basaloid cells, but not the cell balls, expressed CD10, Ber-EP4, BCL-2, and CK7, the latter a previously unreported finding. The histological findings and immunohistochemical profile are compatible with a diagnosis of a trichogerminoma.