Prospective Consensus Reporting by Gynecologic Pathology and Dermatopathology Improves Diagnosis of Vulvar Biopsies.

CONTEXT.­: Vulvar biopsy interpretation and reporting, particularly of vulvar dermatoses, can be challenging in daily practice for both surgical pathologists (SPs) and dermatopathologists (DPs). OBJECTIVE.­: To investigate whether prospective consensus reporting of vulvar biopsies by SPs and DPs would provide value and improve overall diagnostic concordance. DESIGN.­: Consecutive vulvar biopsies during a 6-month period were reviewed prospectively by both gynecologic SPs and DPs. Preliminary, independently generated diagnoses were recorded and then shared in consensus review (SPs+DPs). A third pathologist adjudicated cases without consensus. Multiple data elements were collected for each case: division (SP/DP), age, site, clinical history, diagnostic category, preliminary and final (consensus) diagnosis, need for adjudication, ancillary tests, and diagnostic discrepancy. RESULTS.­: Eighty-four biopsies (48 SP, 36 DP) from 70 patients were reviewed. Forty-two of 84 cases (50%) were neoplastic, 38 of 84 (45%) were reactive/inflammatory, with the remaining (5%) showing both or other features. Independent diagnoses were discrepant in 22 of 84 cases (26%), but consensus review resulted in an agreed-upon diagnosis in all cases, with adjudication required in 6 cases. Independent diagnostic agreement increased over time with a reduction in major and minor discrepancies between the first and second half of the study period. CONCLUSIONS.­: Prospective review of vulvar biopsies by both SPs and DPs can improve overall reporting. Consensus review allows pathologists to gain diagnostic confidence in interpretation of inflammatory (for SPs) and neoplastic (for DPs) vulvar biopsies; therefore, intradepartmental consultation is of value, particularly in select cases.

Hansen Disease (Leprosy) and Armadillo Exposure in Arkansas: A Case Series.

BACKGROUND: Although most cases of Hansen disease (HD) in the United States are imported from endemic areas, a subset of cases are relate to exposure to nine-banded armadillos. Several recent cases of HD in Arkansas occurred in patients who had not traveled to endemic areas and who reported variable degrees of armadillo exposure. OBJECTIVE: The purpose of this study was to report 6 cases of HD diagnosed in Arkansas between 2004 and 2016. The secondary purpose was to explore the correlation between exposure to the nine-banded armadillo as it pertains to transmission of the disease. METHODS: The referring clinician of each patient was contacted to gather information regarding the patient's clinical presentation, armadillo exposure, and travel history. In addition, the Arkansas Department of Health was consulted to review the demographics of individuals diagnosed with HD in the past 15 years and to review the distribution of HD throughout the state of Arkansas. RESULTS: Six domestic cases of HD were associated with both direct and indirect exposure to armadillos. LIMITATIONS: Armadillo exposure may be underreported in patients with HD because of fear of stigmatization and/or lack of access to care. CONCLUSIONS: Direct exposure to armadillos does not appear to be required for transmission of HD making a soil-mediated mechanism of indirect exposure plausible.

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.

ALK Rearrangements Are Infrequent in Cellular Blue Nevus and Deep Penetrating Nevus.

Recent studies have identified kinase fusions in Spitzoid melanocytic neoplasms, and approximately 10% of Spitzoid neoplasms harbor anaplastic lymphoma kinase (ALK) rearrangements and corresponding ALK immunoreactivity. Deep penetrating nevi (DPN), a subset of melanocytic neoplasms, have histologic and immunohistochemical overlap that have historically supported classification of DPN with blue/cellular blue nevi (CBN). However, HRAS mutations have rarely been detected in DPN, thereby also linking them to Spitz nevi. The purpose of this study was to see if DPN or CBN possess ALK rearrangements, thereby providing more evidence that these melanocytic lesions may be pathogenetically related to Spitzoid neoplasms. Using ALK immunohistochemistry as a surrogate for ALK rearrangement, the authors examined 26 DPN, 30 CBN, and 4 conventional blue nevi. ALK immunoreactive cases underwent fluorescent in situ hybridization to investigate for the presence of ALK gene rearrangement. Patchy and focal ALK immunostaining was found in only 1 case of DPN (1/26, 3.8%). Seven cases of CBN (7/30; 23%) showed ALK immunostaining (6 focal/patchy, 1 strong and diffuse). Fluorescent in situ hybridization using ALK break-apart probes showed various degrees of gain of 2p23 and rare ALK break-apart signals. Four CBN showed ALK rearrangement in 2%-4% of cells. Two cases of CBN showed gain of 2p23 in 10%-20% of cells. In our study, ALK rearrangements are uncommon in both CBN and DPN, making ALK an unlikely driver in tumorigenesis and classification of these melanocytic variants. However, our study did identify ALK molecular changes and immunohistochemical staining patterns that have not been previously described in CBN or DPN.

Colliding, colonizing or combining? Four cases illustrating the unique challenges presented by melanoma arising in conjunction with basal cell carcinoma.

Biphasic lesions comprised of melanocytic and epithelial components are rare entities believed to arise either as a collision of 2 histologically distinct lesions in the same anatomic location or as a singular progenitor tumor differentiating along 2 differing lineages. Regardless of mechanism of origin, these tumors present unique challenges in pathologic interpretation and in determining appropriate measurements, which assigns subsequent prognosis to the patient. We present 4 tumors of melanoma co-existing with basal cell carcinoma (BCC) and discuss relevant literature regarding these biphasic entities. Patients consisted of 3 males and 1 female, ranging in age from 62 to 93, with lesions located on the shoulder, frontal scalp, forearm and nose. Three of 4 lesions showed melanoma cells limited to BCC tumor lobules, without evidence of direct dermal invasion by melanoma cells, raising the question of whether or not these tumors should be classified as in situ or invasive melanoma. These cases highlight the complexity that such lesions pose to dermatopathologists, in terms of their uncertain origin and variable microscopic appearance. In the absence of data regarding outcomes for these tumors (given their rarity), it is important to utilize a case-by-case approach, with careful clinical correlation and appropriate use of ancillary techniques.

Metastatic laryngeal large cell neuroendocrine carcinoma: A rare case of presentation and extreme tumor burden.

Large cell neuroendocrine carcinoma (LCNEC) of the larynx is an aggressive form of neuroendocrine carcinoma that affects smokers at an average age of 60 years. LCNEC is characterized by large cells with round to ovoid nuclei distributed in a trabecular or nested growth pattern. Previously, laryngeal LCNEC and atypical carcinoid tumors were considered identical; however, laryngeal LCNEC has been shown to have higher mitotic rates and worse prognosis, which has led to laryngeal LCNEC's being separated from atypical carcinoid and classified as a poorly differentiated neuroendocrine carcinoma in the most recent World Health Organization classification. We present a case of a 56-year-old female who presented with painful subcutaneous skin lesions that were diagnosed as metastatic carcinoma at an outside facility. Subsequent workup revealed a primary epiglottic lesion. Over the next 4 years, she continued to develop over 100 similar subcutaneous nodules. Additional workup confirmed neuroendocrine differentiation, thus clarifying the diagnosis of metastatic LCNEC. Review of literature has revealed only 1 reported case of LCNEC with skin metastasis. This is the first reported case in which skin metastasis was the initial presenting symptom; moreover, our case is unique with regard to the heavy metastatic burden to the skin.

A diagnostically challenging case of CD8+ primary cutaneous gamma/delta T-cell lymphoma.

Primary cutaneous gamma/delta T-cell lymphoma (PCγδTCL) is a rare form of cutaneous lymphoma characterized by abnormal clonal proliferation of mature, activated gamma-delta T cells expressing the γδ heterodimer of the T-cell receptor (TCR). As an entity, PCγδTCL has recently undergone diagnostic revision since its introduction in the 2008 WHO classification of cutaneous lymphomas and confirmedin 2016. Nonetheless, diagnosis remains difficult both clinically and histologically, given its broad range of clinical manifestations and immunohistochemical phenotypes. Herein, we present a rare case of CD8+ PCγδTCL with a discussion highlighting theheterogeneity within this entity.

Cutaneous scalp metastases from retroperitoneal leiomyosarcoma: a case report.

A 71-year-old woman presented with five scalp nodules that were clinically suspicious for pilar cysts. Histopathologic examination showed a proliferation of mitotically active pleomorphic spindle cells arranged into intersecting fascicles in the dermis and subcutis. Tumor cells displayed deeply eosinophilic cytoplasm and expressed desmin but were negative for S100 protein by immunohistochemistry. Before 10 years, the patient was diagnosed with high-grade retroperitoneal leiomyosarcoma and underwent resection with intraoperative radiation. Metastatic disease involving the lungs, liver and soft tissue developed, requiring treatment with resections, radiation and chemotherapy. Owing to the presentation of multiple scalp nodules with microscopic features of leiomyosarcoma in conjunction with the clinical history of retroperitoneal leiomyosarcoma, a diagnosis of metastatic leiomyosarcoma was made. Scalp metastasis from retroperitoneal leiomyosarcoma is extremely rare and portends a poor prognosis. To our knowledge, only two other cases have been reported in the English literature, and a further search discovered only nine additional cases of scalp metastasis from soft tissue leiomyosarcoma of any non-gynecologic anatomic site. This case highlights the striking microscopic similarity between primary cutaneous and metastatic leiomyosarcoma and illustrates the necessity of adequate clinical information and an appropriate index of suspicion in excluding the possibility of cutaneous metastases of leiomyosarcoma from somatic soft tissue.