Mucinous eccrine carcinoma of the vulva with neuroendocrine differentiation

Primary Mucinous Carcinoma of Skin: A Rare Cutaneous Neoplasm. Clinicopathologic Features, Differential Diagnoses, and Review of Literature

ABSTRACT

Primary mucinous carcinoma of the skin (PMCS) is a rare malignant neoplasm of sweat gland origin, with an incidence of 0.07 per million. Histologically, it may be difficult to differentiate it from metastatic mucinous carcinomas of the skin. A case of PMCS is reported here in a 59-year-old woman who presented with a lesion on the right lower eyelid. Histological examination revealed features of mucinous adenocarcinoma. The main differential diagnosis was metastatic mucinous adenocarcinoma; however, the lack of colorectal and lung markers and the presence of focal in situ components were consistent with the diagnosis of PMCS. PMCS and breast mucinous carcinoma share immunohistochemical markers, such as GCDFP-15 and mammaglobin; however, focal in situ component with the presence of myoepithelial cells in the tumor ruled out metastatic mucinous carcinoma of breast origin. The subsequent mammograms did not reveal any breast lesions. Colonoscopy did not show any evidence of colonic malignancy, and imaging studies (CT scan) did not show any evidence of neoplasm in the body. These findings were in keeping with a diagnosis of PMCS. The present case emphasizes the importance of clinicopathological correlation, histopathology, and immunohistochemistry in the accurate diagnosis of PMCS and summarizes the literature on these rare cutaneous neoplasms.

Primary Cutaneous Mucinous Carcinoma: A Review of the Literature

BACKGROUND

Primary cutaneous mucinous carcinoma (PCMC) is an exceedingly rare, low-grade tumor that histologically resembles mucinous carcinoma from other primary sites, such as the breast, gastrointestinal tract, and lungs.

OBJECTIVE

The purpose of this article was to review the current literature on PCMC as it relates to epidemiology, clinical presentation, histopathology, immunohistochemistry, treatment, and prognosis.

MATERIALS AND METHODS

An extensive literature review was conducted using PubMed and Ovid MEDLINE to identify articles related to PCMC.

RESULTS

Several hundred cases have been reported in the medical literature, and surgical resection, whenever feasible, is the standard of care.

CONCLUSION

The diagnosis of primary cutaneous mucinous carcinoma is one of exclusion, requiring a metastatic work-up to rule out distant primary. Mohs micrographic surgery is a tissue sparing technique that allows complete margin control of these rare neoplasia.

Cutaneous Neuroendocrine Mucinous Carcinomas Are Low-grade But May Be Associated With Other Cancers

Primary cutaneous mucinous sweat gland carcinoma is said to be prognostically stratifiable by neuroendocrine differentiation, however, this assertion is based on historical data and older staining techniques. We aimed to evaluate the percentage of mucinous and nonmucinous adnexal tumors expressing the newer, more sensitive neuroendocrine marker insulinoma-associated protein 1 (INSM1), and to assess clinicopathologic features in patients cohorted by this phenotype. Of 12 available adnexal/cutaneous adenocarcinomas, 9 were mucinous, 3/9 of which were INSM1-negative, and 2/3 with nodal metastases. Of 3 nonmucinous cases, all were INSM1-negative, 1/3 with nodal metastasis, and 2/3 with lymphovascular invasion. In contrast, of 6 mucinous INSM1-positive cases, no cases had LVI or metastasis, however, 3 patients died during follow-up, 2 from breast or urothelial cancer. A fourth patient developed breast carcinoma. INSM1-positive tumors, from cheek (3), scalp (2), and chin (1) were estrogen receptor and progesterone receptor positive. No cases of apocrine adenoma or hidrocystoma, basal cell, or sebaceous carcinoma labeled with INSM1. While most primary cutaneous mucinous carcinomas are of the neuroendocrine type, our study confirms the presence of occasional non-neuroendocrine mucinous carcinomas. We validate the association of such tumors and nonmucinous non-neuroendocrine adnexal carcinoma with intermediate-grade behavior, including lymph node metastases, but not death. Conversely, neuroendocrine expressing primary cutaneous mucinous carcinoma may represent the well-differentiated neuroendocrine neoplasm/neuroendocrine tumor primary to skin, with low-grade behavior, but attendant risk of germline susceptibility to other aggressive extracutaneous tumors. Routine assessment of cutaneous adnexal carcinoma with INSM1 and longer term follow-up and cancer screening of patients with positive staining is recommended.

Recurrent Neuroendocrine Primary Cutaneous Mucinous Carcinoma of the Scalp After Complete Excision

ABSTRACT

Primary cutaneous mucinous carcinoma is a rare, indolent malignancy with a debated history regarding cell of origin. Recurrence is rare but has been documented in up to a third of cases. Recent literature reviews have recognized 2 possible subtypes-neuroendocrine and nonneuroendocrine- with different possible prognostic implications for patients. We describe a case of recurrent primary cutaneous mucinous carcinoma in a 50-year-old man with subtle neuroendocrine features not initially recognized on routine H&E staining but highlighted by immunohistochemical studies. We underscore the importance of immunohistochemical use in these rare cases and emphasize that awareness of these neuroendocrine and nonneuroendocrine subtypes is essential for a complete diagnosis.

Endocrine mucin-producing sweat gland carcinoma and associated primary cutaneous mucinous carcinoma: Review of the literature

BACKGROUND

Endocrine mucin-producing sweat gland carcinoma (EMPSGC) is a rare, low-grade, cutaneous adnexal carcinoma with neuroendocrine differentiation. It is considered to be a precursor of invasive neuroendocrine type primary cutaneous mucinous carcinoma (PCMC).

OBJECTIVE

To review clinicopathological literature summary of EMPSGC and associated neuroendocrine PCMC from all reported cases and compare its behavior vs non-neuroendocrine PCMC data reported in the literature.

METHODS

A review of English literature of all EMPSGC cases with and without associated PCMC was carried out.

RESULTS

EMPSGC was associated with invasive neuroendocrine type PCMC in 35.7% of cases. We found the recurrence rate of PCMC associated with EMPSGC of about 12.3%, which is much less than the 30% recurrence rate reported for the non-neuroendocrine subtype of PCMC. The non-neuroendocrine subtype of PCMC shows a 4% and 11% rate of distant and lymph node metastasis, respectively, vs EMPSGC-associated neuroendocrine type of PCMC, which is very indolent and only one recent case of locoregional metastasis out of 190 EMPSGC cases has been reported so far.

LIMITATION

Limitation of our study includes data derivation from case reports and case series in the literature.

CONCLUSION

The prognostic benefits for this cohort of patients may be considered in their overall management.

Neuroendocrine Differentiation of Skin Tumors: A Comprehensive Review

Neuroendocrine differentiation is characterized by endocrine and neuronal features with prominent dense secretory granules and neuropeptides. Neuroendocrine differentiation of skin tumors is of unknown clinical significance. Nonetheless, the acknowledgment of this line of differentiation is important to prevent diagnostic pitfalls and subsequent inappropriate management. This review aims at summarizing the skin neoplasms that can express neuroendocrine markers.

An Update on Endocrine Mucin-producing Sweat Gland Carcinoma: Clinicopathologic Study of 63 Cases and Comparative Analysis

Endocrine mucin-producing sweat gland carcinoma (EMPSGC) is a rare, low-grade adnexal neoplasm with predilection for the periorbital skin of older women. Histologically and immunophenotypically, EMPSGC is analogous to another neoplasm with neuroendocrine differentiation, solid papillary carcinoma of the breast. Both lesions are spatially associated with neuroendocrine mucinous adenocarcinomas of the skin and breast, respectively. EMPSGC is ostensibly a precursor of neuroendocrine-type mucinous sweat gland adenocarcinoma (MSC), a lesion of uncertain prognosis. Non-neuroendocrine MSC has been deemed locally aggressive with metastatic potential, and previous works speculated that EMPSGC-associated (neuroendocrine-type) MSC had similar recurrence and metastatic potential with implications for patient follow-up. Only 96 cases of EMPSGC have been reported (12 cases in the largest case series). Herein, we present 63 cases diagnosed as "EMPSGC" in comparison with aggregated results from known published EMPSGC cases. We aim to clarify the clinicopathologic features and prognostic significance of the neuroendocrine differentiation of EMPSGC and its associated adenocarcinoma and to determine the nosological relevance of EMPSGC association in the spectrum of MSC histopathogenesis. Results established an overall female predominance (66.7%) and average presenting age of 64 years. EMPSGC lesions were associated with adjacent MSC in 33.3% of cases. The recurrence rate for neuroendocrine-type MSC was ~21%, less than the reported 30% for non-neuroendocrine MSC. There were no cases of metastasis. EMPSGC and neuroendocrine-type MSC are distinct entities with more indolent behavior than previously reported, supporting a favorable prognosis for patients.

Endocrine Mucin-Producing Sweat Gland Carcinoma: Two New Eyelid Cases and Review of the Literature

Endocrine mucin-producing sweat gland carcinoma (EMPSGC) is a rare low-grade sweat gland carcinoma. It is clinically often mistaken for basal cell carcinoma and presents a low rate of local recurrence. In this article, we present 2 new cases of EMPSGC arising in a similar location (left lower eyelid) and review the literature on this topic. One patient is a 72-year-old male with complete excision and no evidence of recurrence after 17 months of surveillance. The second patient is a 77-year-old female with incomplete initial excision and local recurrence after 38 months. p63 immunostain was negative in both cases. EMPSGC should be suspected in elderly patients with lesions of eyelids. Histologically, it should be considered and worked up if the lesion is separated from the overlying epidermis and presents a mucinous component. Complete excision is advised to avoid local recurrences.

Vulvar mucinous adenocarcinoma with neuroendocrine differentiation: A case report and review of the literature

BACKGROUND

There are limited cases in literature of patients with mucinous adenocarcinoma of the vulva with neuroendocrine differentiation have. With this new case, we aim to provide an overview of the existing literature and present a tool with relevant markers for the pathologist in the differential diagnosis.

CASE DESCRIPTION

A 92-year-old multiparous, Caucasian woman presented with a 8 cm spherical tumor of the left major labium. Since the initial punch biopsy was not conclusive, a local resection was performed. Histopathological examination showed mucus production, large pools of mucin with trabeculae and cribriform glandular structures with strongly atypical columnar epithelium. Additional immunohistochemical analysis demonstrated expression of: CEA, CK7, EMA, and the neuroendocrine markers synaptophysin and chromogranin supporting the diagnosis.

CONCLUSION

In this report, we present a new case of a mucinous adenocarcinoma of the vulva with neuroendocrine differentiation based immunohistochemical analysis. Due to the indolent tumor behavior, partial vulvectomy is the therapy of choice.

Primary mucinous adenocarcinoma of the vulva: A case report and review of the literature

Primary vulvar cancer is a rare disease with an incidence of 2-3 per 100,000 women. The vast majority of vulvar carcinomas are of the squamous cell type (90%). Primary vulvar adenocarcinomas rank among the rare gynecological malignancies. We herein present a case of a vulvar mass near the vaginal orifice, the biopsy of which revealed a mucinous adenocarcinoma. Local excision was performed, followed by postoperative chemotherapy. The patient was asymptomatic and developed no recurrence during the 2 years of follow-up after surgery and chemotherapy. We consider local excision, with or without chemotherapy, to be an effective therapeutic approach to this type of tumor. However, further studies are required to support our conclusions for early-stage vulvar mucinous adenocarcinoma.

WT1 expression in endocrine mucin-producing sweat gland carcinoma: a study of 13 cases

BACKGROUND

Endocrine mucin-producing sweat gland carcinoma (EMPSGC), a low-grade sweat gland carcinoma with a predilection for the eyelids, often shows areas of benign eccrine cysts, atypical intracystic proliferation and associated mucinous carcinoma, suggesting tumor progression. Wilms tumor 1 (WT1) protein, a transcription factor, is overexpressed in many tumors and plays a role in oncogenesis.

METHODS

A computer-based search for tumors diagnosed between 1989 and 2009 was conducted. Clinical data were obtained from pathology reports and patient records. Biopsies were reviewed for histologic features. Immunostaining was performed for WT1, chromogranin, synaptophysin, estrogen receptor (ER), epithelial membrane antigen (EMA), polyclonal carcinoembryonic antigen (P-CEA), cytokeratin 7 (CK7), cytokeratin 20 (CK20) and MIB-1.

RESULTS

Eight women and five men (mean age: 61.2 years; range: 40-77 years) presented with slow-growing eyelid nodules. Cases of EMPSGC were characterized by the presence of dermal nodules with various growth patterns. Adjacent eccrine cysts were present in five patients, atypical epithelial proliferation within the cyst wall in four patients, and an associated mucinous carcinoma in one patient. All tumors were positive for WT1, CK7, ER, P-CEA and EMA and negative for CK20. Tumors were positive for synaptophysin in 12 cases and chromogranin in nine cases. The MIB-1 proliferation index was low in most cases. No WT1 staining was observed in the overlying epidermis, adnexal structures or areas of benign eccrine cyst. WT1 expression was observed in areas of atypical epithelial proliferation, and the neoplastic cells.

CONCLUSIONS

The present study shows WT1 expression in the neoplastic epithelial cells of EMPSGC, areas of atypical intraductal proliferations, and mucinous carcinoma. The absence of WT1 expression in areas of benign eccrine cyst and cutaneous sweat glands suggests WT1 upregulation plays a role in tumor cell proliferation and progression of EMPSGC.

Neighboring look-a-likes: distinguishing between breast and dermatologic lesions

Due to the proximity of the skin, subcutis, and axilla to the breast, the possibility of a "breast mass" actually representing a dermatologic lesion should be considered, particularly if the proliferation does not look characteristically "mammary" in appearance. Even more underappreciated is the scenario of a dermatologic proliferation morphologically masquerading as a breast tumor. The pathologist can fall prey to this pitfall if he/she is led to believe that the location of the tumor is the breast proper. The aim of this review is to provide an overview of dermatologic mimickers of breast lesions and helpful ways to discern between them when possible.

Working formulation of neuroendocrine tumors of the skin and breast

In the skin and breast, endocrine tumors are composed of a heterogeneous mixture of endocrine and exocrine cells. The definition of "pure" endocrine carcinomas is a matter for debate, and as a consequence, there is lack of uniform diagnostic criteria. There are no significant clinical differences in either overall or disease-free survival between matched neoplasms with endocrine and without endocrine differentiation nor between the degree of endocrine differentiation and tumor size, stage, or prevalence of vascular invasion for both sites (skin and breast). Here, endocrine tumors of the skin and breast are grouped respectively into three categories that include most of the neuroendocrine tumors of the skin and breast as seen in routine practice. It was felt that the number of different types of neuroendocrine tumors is so conspicuous that it is impossible to organize them in an orderly classification. It has been proposed therefore, for practical diagnostic routine purposes, to arrange these neoplasms into a working formulation. The latter includes heterogeneous lesions respectively of the skin and breast within the same group that have clinical features in common.

Mucin-producing sweat gland carcinoma of the eyelid: diagnostic and prognostic considerations

PURPOSE

To describe the clinical and pathologic characteristics of mucin-producing sweat gland carcinoma of the eyelid and to determine whether neuroendocrine differentiation is of prognostic significance.

DESIGN

Retrospective interventional case series.

METHODS

Search of the New York Eye and Ear Infirmary pathology database between 1990 and 2011 identified 16 patients with mucin-producing sweat gland carcinoma. Clinical, histopathologic, and immunohistochemical analyses were performed on all identified cases.

RESULTS

The patients presented with vascularized, focally cystic, nonulcerated eyelid margin lesions. Histopathologic evaluation showed that 4 lesions (25%) had a cystic, papillary, and solid growth pattern with an in situ component, 7 (44%) were pure invasive mucinous carcinomas, and 5 (31%) demonstrated both growth patterns. Immunohistochemical analysis of 15 tumors showed that pure cystic/papillary lesions had a significantly greater percentage of synaptophysin-immunoreactive cells (P = .036). There was no significant difference in the number of neuroendocrine markers expressed or in the intensity of immunostaining among the 3 different growth patterns. Re-excision for margin clearance was performed in 8 of 13 cases (61.5%). Two of 13 lesions recurred (15%); 1 of these was an in situ tumor with cystic morphology and neuroendocrine differentiation and the other was pure invasive mucinous carcinoma. None of the lesions metastasized.

CONCLUSIONS

Mucin-producing sweat gland carcinoma pathologically represents a continuum, from an in situ lesion to a classic, invasive mucinous carcinoma. Immunohistochemical evidence of neuroendocrine differentiation can be observed in all lesions and does not appear to have a prognostic significance, arguing against the utility of immunohistochemical subtyping of mucinous sweat gland carcinomas.

Intracranial and spinal metastases from eccrine mucinous carcinoma: case report

BACKGROUND AND IMPORTANCE

Mucinous eccrine carcinoma (MEC) is a rare but distinct type of sweat gland tumor. MECs tend to recur locally, and their spread to distant organs is very uncommon. This article describes the first case of MEC metastasizing to the brain and the spine.

CLINICAL PRESENTATION

A 45-year-old female presented with a 2-year history of a scalp mass in the occipital area with lymph node spread. She underwent excision of the mass and neck lymph node dissection. Pathology confirmed the diagnosis of MEC. Postoperatively, she received radiation to the involved areas. Four years later the patient presented with left hemiparesis and underwent craniotomy for gross total resection of the metastasis. This recurred after 2.5 years and she underwent another craniotomy for gross total resection followed by whole brain radiation. In addition, the patient had metastases to T11 vertebral body and the left C6 to 7 neural foramen. Moreover, the patient developed leptomeningeal disease in the spine. The metastases to the spine were treated with radiation therapy. The patient died 1.5 years later.

CONCLUSION

Even though it is rare for MEC to spread to distant organs, physicians should be aware of the risk of metastatic invasion of the brain and spine and be vigilant about surveillance of these sites. MEC metastases to the brain should be treated aggressively with surgical resection followed by stereotactic radiosurgery to the tumor bed. Spine metastases should be treated with a combination of surgery and image-guided radiation therapy, depending on the degree of cord compression from epidural metastatic disease.

Mucinous sweat gland adenocarcinoma of the eyelid - current knowledge of a rare tumor

PURPOSE

To review the medical literature on mucinous sweat gland adenocarcinoma of the eyelid (MSA) and present two new cases.

METHODS

Details of published case reports and small series (between 1971-2010) were evaluated and summarized including two patients diagnosed and treated at our institution. Data regarding age, gender, ethnicity, precise location, clinical presentation, treatment and follow up of each patient were collected.

RESULTS

25 reports describing 55 patients were found in the medical literature. The mean age was 61.3 years (30-87), 22(59%) were male and 28(80%) were Caucasian. In 23(44.2%) patients the lesion was in the lower lid, in 20(38.5%) in the upper lid, in 3(5.7%) involving both lids and in 6(11.6%) in a canthus. In 12(21.8%) patients a lesion with a benign diagnosis was previously excised from the same location. In 2 of them histological re-examination resulted in a diagnosis of MSA. Intraorbital involvement was found in 2(3.6%) patients. Regional lymph node metastasis was found in 2(4.4%) patients. Surgical excision was the treatment of choice using Mohs' micrographic-controlled excision technique in recent years. Radiotherapy was applied to 2 patients with clinical resolution in 1. Recurrence of the tumor was reported in 14(30%) patients.

CONCLUSIONS

MSA is a rare tumor of the eyelid with no clinically distinguishing features. It should be suspected particularly with recurrent eyelid lesions and must be differentiated from metastatic disease. The tumor may extend into the orbit and metastasize regionally. Surgical removal with continued regular follow-up examination is the treatment of choice.

A case of primary cutaneous mucinous carcinoma with neuroendocrine differentiation

Primary cutaneous mucinous carcinoma is a rare malignant tumor that originates from the deepest portion of the eccrine sweat duct. Common sites of involvement are the face and scalp. Biopsy shows dermal epithelial cell islands embedded in mucin pools separated by fibrous septae. It is difficult to differentiate this tumor histologically from metastatic adenocarcinoma. Recurrence after excision is common but metastases are rare. We report a primary cutaneous mucinous carcinoma with neuroendocrine differentiation on the right cheek of a 63-year-old man.

"Pagetoid" eccrine carcinoma of the vulva: report of an unusual case with review of the literature

Sweat gland carcinoma of the vulva is rare and may be classified as being of eccrine, apocrine, or mixed origin. Most reported cases of vulvar sweat gland carcinomas associated with extramammary Paget disease describe a tumor of apocrine origin. We report a case of a vulvar sweat gland carcinoma of eccrine origin associated with Pagetoid extension. A review of the literature and the differential diagnosis are also presented. To our knowledge, this is the second case of vulvar sweat gland carcinoma of eccrine origin associated with extramammary Paget disease.

Primary cutaneous neuroendocrine cell carcinoma (Merkel cell carcinoma) with prominent microcystic features, mimicking eccrine carcinoma

Although primary cutaneous neuroendocrine cell carcinoma [Merkel cell carcinoma (MCC)] may show divergent features, including microcystic ('tubuloglandular'), squamous, eccrine and rhabdomyoblastic, a diffuse microcystic pattern is exceedingly rare. In this study, we present two cases of MCC with prominent microcystic features, which precluded a definitive diagnosis in the initial punch biopsy. Both patients were middle-aged men with a history of rapidly growing plaques of the back or posterior neck. Punch biopsies from both patients revealed an infiltrating neoplasm with prominent microcystic features that mimick tubuloglandular structures, lined by hyperchromatic basaloid cells, which were strongly positive for chromogranin and BerEP4, variably positive for CK7 and CK5/6 and negative for CK20, synaptophysin, S-100, epithelial membrane antigen (EMA), gross cystic disease fluid protein-15 (GCDFP-15), estrogen/progesterone receptors (ER/PR), thyroid transcription factor 1 (TTF1) and carcinoembryonic antigen (CEA). The re-excision specimens showed a multifocal intra-epidermal component in one case and typical finely stippled nuclear chromatin in both cases. Although the lack of CK20 staining is unusual, the histologic characteristics along with the remaining immunohistochemical studies favor the diagnosis of a primary cutaneous neuroendocrine cell carcinoma over the variants of eccrine carcinoma or basal cell carcinoma with neuroendocrine differentiation. Our cases illustrate that prominent microcystic features, mimicking glandular differentiation, may occur in MCC and pose a diagnostic challenge in small biopsy specimens.

Endocrine mucin-producing sweat gland carcinoma: report of a case and review of the literature

Mucinous carcinoma of skin (MCS) is an uncommon adnexal tumor of disputed differentiation. In 1995, Rahilly et al. reported a case of MCS with neuroendocrine differentiation (E-MCS). Since that report, seven additional cases have been published. Here, we report on a case of E-MCS and discuss the differential diagnoses.

Malignant adnexal neoplasms

Malignant cutaneous adnexal neoplasms are one of the most challenging areas of dermatopathology. Tumors of the pilosebaceous apparatus can occur as single-lineage neoplasms or may manifest as complex proliferations with multilineal differentiation patterns including not only the germinative component of the hair bulb, the inner or outer root sheath epithelium and the sebaceous gland and duct, but also the sweat duct components that relate to the apocrine secretory apparatus which empties into the follicle near the follicular bulge. Eccrine and apocrine neoplasms present a bewildering array of morphologies, which often defy precise classification. The purpose of this review is to discuss in detail the malignant neoplasms of the cutaneous adnexae and their benign and prognostically indeterminate mimics.

Mucinous Eccrine Adenocarcinoma of the Periocular Region

PURPOSE

To report 4 patients with mucinous eccrine adenocarcinoma of the periocular region.

METHODS

Interventional case series of 4 patients with mucinous eccrine adenocarcinoma of the periocular region treated at 2 centers.

RESULTS

Two patients with mucinous eccrine adenocarcinoma of the upper eyelid, 1 with mucinous eccrine adenocarcinoma of the lower eyelid, and 1 with mucinous eccrine adenocarcinoma of the eyebrow were included in this report. The lower eyelid lesion and the eyebrow lesion recurred after Mohs micrographic surgery. Both recurrent lesions were treated with Mohs micrographic surgery and postoperative adjuvant external-beam radiation therapy. The other 2 primary tumors were treated with wide local excision with frozen section control of margins and did not recur. The follow-up time after the most recent surgical procedure ranged from 8 to 17 months (median, 12 months).

CONCLUSIONS

Mucinous eccrine adenocarcinoma is a rare ocular adnexal neoplasm that can involve the eyelid and periocular skin, can be locally invasive, and has a high risk of local recurrence despite Mohs surgery.

Endocrine Mucin-Producing Sweat Gland Carcinoma

Endocrine mucin-producing sweat gland carcinoma (EMPSGC) is an underrecognized low-grade carcinoma with predilection to the eyelid. Only 4 cases of this entity have been described in the literature. Here, we describe 12 cases of EMPSGC. The lesions were twice as frequent in females than males with an average age of 70 years (range, 48-84 years). Clinically, they presented as a slowly growing cyst or swelling. The most common site of occurrence was the lower eyelid (8 cases). Two lesions occurred on the upper eyelid and 2 on the cheek. Histologically, they were well-circumscribed, typically multinodular tumors with solid or partially cystic nodules, frequently showing areas of papillary architecture. Focal cribriform arrangements were also present. The nodules were formed by uniform small- to medium-sized oval to polygonal epithelial cells with lightly eosinophilic to bluish cytoplasm. The nuclei were bland with diffusely stippled chromatin and inconspicuous nucleoli. Intracytoplasmic and extracellular mucin was usually present. Mitotic activity was present but never brisk. All tumors examined immunohistochemically expressed at least one neuroendocrine marker, synaptophysin or chromogranin. CD57 and neuron specific enolase, secondary markers of neuroendocrine differentiation, were expressed in most cases. All tumors tested expressed estrogen and progesterone receptors, cytokeratin 7, low molecular cytokeratin Cam5.2, and epithelial membrane antigen and were negative for cytokeratin 20 and S-100 protein. Calponin, smooth muscle actin, and p63 immunohistochemical stains did not disclose myoepithelial cells around larger tumor nests in most cases, supporting the notion that EMPSGC is an invasive carcinoma. In 10 cases, cystic areas lined by benign epithelium indistinguishable from eccrine ducts were present. In some foci, the benign ductal epithelium was undermined or replaced by carcinoma in situ with similar cytologic features to the solid or papillary areas of EMPSGC. Myoepithelial cells were preserved in the areas of in situ carcinoma. In 6 cases, EMPSGC was associated with invasive mucinous carcinoma. In situ carcinoma and mucinous carcinoma also expressed neuroendocrine markers. Clinical follow-up showed no recurrences or metastases, consistent with low-grade carcinoma. The series provides histologic evidence for a multistage progression of noninvasive sweat gland neuroendocrine carcinoma to EMPSGC and then to mucinous carcinoma of the eyelid. Although the data from this series support the notion that the prognosis of EMPSGC and mucinous carcinoma is good, longer follow-up is needed for better understanding of their pathogenesis and clinical behavior.

Mohs Micrographic Surgery of Primary Cutaneous Mucinous Carcinoma Using Immunohistochemistry for Margin Control

BACKGROUND

Primary cutaneous mucinous carcinoma is a rare adnexal malignancy with a high recurrence rate following conventional excision and the potential for aggressive local invasion.

OBJECTIVE

To enhance the microscopic detection of mucinous carcinoma in Mohs micrographic surgical sections by incorporating rapid immunohistochemical staining.

METHODS

Standard Mohs micrographic surgical technique was used in conjunction with frozen section immunohistochemistry using an antibody to low-molecular-weight cytokeratin.

RESULTS

Rapid immunoperoxidase staining using low-molecular-weight cytokeratin detected residual foci of mucinous carcinoma that were difficult to identify on routine frozen sections. Immunostaining was strongly positive in areas with clear evidence of tumor by routine histology, as well as in adjacent areas on a subsequent stage where frozen sections were equivocal or negative. Immunostaining was distinctly negative at the final surgical margin, which was shown by en face permanent sections to be free of tumor. The patient has been free of recurrence for 3 years.

CONCLUSION

Immunoperoxidase-guided Mohs micrographic surgery using low-molecular-weight cytokeratin enhances the sensitivity for detection of mucinous carcinoma, and may help contribute to complete tumor removal.

Invasive mucinous (colloid) adenocarcinoma of ectopic breast tissue in the vulva: a case report

We present the first case of primary vulvar mucinous adenocarcinoma of ectopic breast origin. The patient is an 84-year-old woman with a mass on the left side of her vulva. A left partial vulvectomy with bilateral inguinal lymph node dissections revealed a mucinous adenocarcinoma that involved the dermis and subcutaneous tissue. The tumor cells were positive for estrogen receptors (ERs), progesterone receptors (PRs), and BRST-1 markers. The clinical and pathologic features, differential diagnosis, and treatment are discussed.

Mucinous Adenocarcinoma of Ectopic Breast Tissue of the Vulva

Ectopic breast tissue has been described rarely in the vulva and is known to develop a variety of pathologic changes. Our review of the literature found a total of 11 reported cases of primary infiltrating ductal adenocarcinoma arising in ectopic breast tissue of the vulva. We report what we believe is the first case of primary mucinous adenocarcinoma arising in ectopic breast tissue of the vulva diagnosed by characteristic histopathologic features and immunohistochemical stain results. We discuss the criteria used in diagnosis of primary breast carcinoma of the vulva and review previously reported cases.

A case of primary mucinous carcinoma of the scalp treated with mohs surgery

BACKGROUND

Primary mucinous carcinoma of the skin is a rare sweat gland malignancy that is associated with locally aggressive behavior and a high rate of local recurrence following simple excision.

OBJECTIVE

A patient with primary mucinous carcinoma of the scalp, which was treated with Mohs micrographic surgery (MMS), is described.

METHODS

Case report and literature review.

RESULTS

The patient underwent MMS to remove the tumor. Thirty months after the procedure, the patient remains tumor free.

CONCLUSION

Simple excision of primary mucinous carcinoma of the skin is associated with a high recurrence rate. Given the low rate of metastasis and characteristic histologic tumor continuity associated with primary mucinous carcinoma of the skin, as well as the tendency for the tumor to involve cosmetically sensitive areas, such as the face and eyelids, MMS appears to represent a preferable treatment alternative for this particular sweat gland tumor. MMS appears to be associated with a very low risk of tumor recurrence.

Immunohistochemical analysis of cytokeratin and human milk fat globulin expression in mucinous carcinoma of the skin

BACKGROUND

Mucinous carcinoma of the skin (MCS) is a rare epithelial tumor which arises primarily in the skin. Metastatic MC from extracutaneous sites, especially breast or colon, mimics MCS and cannot be differentiated from MCS by routine histology alone.

METHODS

Nine cases of MCS were analyzed immunohistochemically using monoclonal antibodies against cytokeratins (CKs) and human milk fat globulin 1 (HMFG) in order to clarify their nature and compare the immunophenotypes with those of other MCs studied in the literature.

RESULTS

Expression of simple epithelial CKs in most of the tumor cells of all cases studied and co-expression of simple and stratified epithelial CKs in some tumor cells of two cases were recognized. CK 20 expression could not detected in any tumor cells. Focal HMFG expression in the luminal or outer surface of the nests was observed in three cases.

CONCLUSION

From CKs expression, MCS was speculated to differentiated mainly toward the secretory cells of the sweat glands, and some tumor cells toward the transient portion between the dermal duct and the secretory portion. Focal HMFG expression suggested either a consequence of malignant transformation or apocrine differentiation. No expression of CK 20 in MCS suggests that we may exclude the diagnosis of metastatic colorectal MC which expressed CK 20.

Villoglandular adenocarcinoma of the vulva

BACKGROUND

Only two previous cases of villoglandular adenocarcinoma of the vulva, an entity morphologically similar to tumors found in the uterine cervix and colorectum, have been reported. This paper communicates the first complete immunohistochemical study in villoglandular adenocarcinoma in order to determine its phenotype and histogenesis.

CASE

A 69-year-old woman had a 1.5-cm nodule in the right labium majus. Histologically, it corresponded to a minimally atypical, villoglandular adenocarcinoma with a small microinvasion. Immunohistochemically, it was positive to OC125, CEA, and OC19.9 and coexpressed cytokeratins 7 and 20. Chromogranin, nuclear estrogen, and progesterone receptors were negative.

CONCLUSION

Phenotypic expression was more consistent with a papillary mucinous ovarian or cervical neoplasm than of a colonic one. Its behavior was similar to that of its morphologic counterpart in the cervix, since the patient had no recurrence 3 years after a wide local excision.

Primary neuroendocrine (Merkel cell) carcinoma of the skin: morphologic diversity and implications thereof

A significant proportion of primary neuroendocrine cell carcinomas of the skin (Merkel cell carcinomas [MCCs]) have been reported to occur in intimate association with malignant epithelial neoplasms, mainly squamous cell carcinomas. In addition, divergent differentiation within these tumors, particularly of squamous and eccrine types, is not infrequent. This expanded morphologic spectrum of MCC calls for evaluation of potential biologic implications of the phenotypic diversity and begs reconsideration of the histogenesis of the lesion. The current retrospective review of 29 cases of primary cutaneous neuroendocrine cell carcinoma aims to address these issues by integrating new information with that which is extant. Eleven tumors were associated with evolving or established cutaneous carcinomas: 2 actinic keratoses, 5 Bowen's disease, 3 superficial squamous cell carcinomas, and 1 basal cell carcinoma. Two combined squamous-neuroendocrine tumors occurred in recipients of solid organ transplants, and another developed in a Marjolin's ulcer at the site of a previous burn. Squamous and/or adnexal differentiation within the dermal component of the tumor was observed in 4 instances and was significantly associated with MCCs in intimate association with another cutaneous carcinoma. The outcome of the group as a whole is similar to that recorded in previous series of MCC, with local recurrence in 32% of cases and death caused by the neoplasm in 28%. Only 52% of the patients were alive with no history of metastasis at follow-up. No significant difference in outcome was observed between the patients with pure MCCs and those with MCCs in combination with another cutaneous carcinoma.

Primary mucinous carcinoma of the skin

Primary mucinous carcinomas of the skin are very rare. To date, 120 cases have been described in the literature. This tumor is a histologic subtype of sweat gland carcinoma. Because of the histopathologic appearance, primary mucinous carcinoma of the skin can be mistaken for metastasis from extracutaneous sites. We report on the cases of two elderly women with mucinous carcinomas arising in the scalp. Immunohistochemical staining of both tumors was positive for low-molecular-weight cytokeratin and epithelial membrane antigen. Carcinoembryonic antigen was positive in Case 2. Neuroendocrine features represented by neuron-enolase-specific positivity were also observed in both cases, and Grimelius and chromogranin A positivity were observed in Case 2. In both cases, there was strong positivity for estrogen receptor and progesterone receptor. Image analysis cytometry showed a diploid DNA content with a low rate of proliferative cells and negativity for p53 and c-erbB-2 proteins in agreement with the low aggressiveness of these neoplasms.

Endocrine mucin-producing sweat gland carcinoma: a cutaneous neoplasm analogous to solid papillary carcinoma of breast

We describe two cases of a distinctive in situ and invasive cutaneous adnexal neoplasm occurring in the eyelid. Mucinous carcinoma represented the invasive portion of the tumor in one case, whereas the other infiltrated in small solid nests. The in situ component is identical to the recently described solid papillary carcinoma of the breast (endocrine ductal carcinoma in situ). Both tumors produced intra- and extracellular mucin, exhibited endocrine differentiation by immunohistochemistry and ultrastructural analysis, and were positive for estrogen and progesterone receptors.