Sebaceous Carcinoma in Situ Masquerading Clinically and Histologically as Paget Disease of the Breast.

Sebaceous carcinoma in situ is a poorly understood and ill-defined entity. In situ sebaceous carcinoma exhibits a similar location pattern to its invasive counterpart in that most commonly has a periorbital distribution. Review of the literature found only seven cases of extraocular sebaceous carcinoma in situ. We present a unique and challenging case of sebaceous carcinoma in situ masquerading both clinically and histologically as Paget's disease of the breast. A 61-year-old female presented to her dermatologist complaining of a 6 mm erythematous waxy papule on her medial right breast. The patient's past medical history was significant for Muir-Torre syndrome. Clinically, the differential diagnosis included Paget disease of the breast, squamous cell carcinoma, and sebaceous carcinoma. A shave biopsy revealed an atypical proliferation of large single cells limited to the epidermis infiltrating in a pagetoid pattern, as well as cohesive nests of round neoplastic cells with mild nuclear atypia, prominent nucleoli, and vacuolated cytoplasm. Histologically, the differential diagnosis included Paget's disease of the breast, squamous cell carcinoma in situ, melanoma in situ, and sebaceous carcinoma in situ. A battery of immunohistochemical stains was performed including CK7, EMA, CAM5.2, CK20, and MART-1. The lesional cells were positive for adipophilin, factor XIIIa, CK7, and EMA and were negative for CAM5.2, CK20, and MART-1 supporting a diagnosis of sebaceous carcinoma in situ. Multiple deeper sections were examined and invasion beyond the epidermis was not identified. This case adds to the paucity of information available regarding extraocular sebaceous carcinoma in situ and warns clinicians of this potential diagnostic pitfall especially in patients with Muir-Torre syndrome.

Primary Cutaneous Osteosarcoma.

Primary cutaneous osteosarcoma is an exceedingly rare malignant mesenchymal neoplasm of the skin which produces bone, osteoid, or chondroid material and does not involve the underlying bone. The most common site for extraskeletal osteosarcoma is in the deep soft tissues of the thigh, upper extremities, and retroperitoneum; however, it may occur anywhere in the body. Involvement of the skin is rare and when it does occur it is more commonly due to metastatic disease rather than a primary malignancy. Only 16 cases of primary cutaneous osteosarcoma have been described in the literature. We report an uncommon case of primary cutaneous osteosarcoma. Our patient is an 84-year-old male with an unremarkable medical history who presented to the dermatology clinic complaining of a 0.5 x 0.4 cm pink flesh to translucent-appearing, shiny, papule on the right superior jawline which was not connected to the underlying bone. Clinically the differential diagnosis included basal cell carcinoma, trichoepithelioma, and other cutaneous adnexal tumors. An excisional biopsy was performed which demonstrated an unremarkable epidermis with a hypercellular reticular dermis with occasional large spindled cells with amphophilic cytoplasm. The deep dermis was involved by mature osteoid formation and infiltration of highly mitotically active, atypical epithelioid and spindled cells with abundant nuclear pleomorphism, amphophilic cytoplasm, and poorly defined cell borders. Occasional multinucleate forms were seen. Immunohistochemistry was performed which showed strong positive staining with vimentin. Without connection to the underlying bone, osteosarcoma of periosteal, parosteal, or osseous origin was excluded. Based on these histomorphologic findings, a diagnosis of primary cutaneous osteosarcoma was made. Our case adds to the dearth of literature regarding primary cutaneous osteosarcoma and provides primary care physicians, dermatologists, and pathologists much needed insight into this rare condition.

Scleroderma-like skin changes induced by checkpoint inhibitor therapy.

Checkpoint inhibitors have emerged as beneficial therapies in many different types of malignancy. The most common toxicities of checkpoint inhibitors are immune-related adverse events (irAEs). As clinical experience with these agents increases, more irAEs have been described. We report a case of scleroderma-like skin changes induced by checkpoint inhibitor therapy. A 61-year-old man was treated with nivolumab for oligometastatic renal cell carcinoma. He initially tolerated the therapy well, but after 16 treatments he began experiencing skin thickening and edema of the abdominal wall, which progressed down the trunk and legs. A punch biopsy revealed epidermal attenuation overlying thickened dermal collagen with entrapment and displacement of the eccrine coils and loss of periadnexal adipose tissue. Focally increased plasma cells were present near the junction of the dermis and subcutaneous adipose tissue. Loss of CD34 staining was seen throughout the dermis. These findings were consistent with a diagnosis of scleroderma. After discontinuation of nivolumab and initiation of steroid therapy, the patient's symptoms significantly improved. This case is among the first reports of scleroderma-like changes induced by a checkpoint inhibitor.

A Case of Small Cell Lung Carcinoma in a 15-Year-Old Boy and Literature Review.

Small cell lung carcinoma (SCLC), also known as high-grade neuroendocrine tumor of the lung, is exceedingly rare in the pediatric population. SCLC is usually fast growing and often has metastasized at diagnosis. It frequently responds well to therapy initially, however, has a high relapse and mortality rate. There are limited published data on SCLC in children and no existing pediatric treatment protocols. In this report, we present a case of extensive stage SCLC in a 15-year-old boy who responded to single-agent gemcitabine therapy and review similar cases reported in the medical literature.

Evaluation and comparison of staining patterns of factor XIIIa (AC-1A1), adipophilin and GATA3 in sebaceous neoplasia.

BACKGROUND: Reliable nuclear immunohistochemical stains for sebaceous neoplasms have not been readily available. Positive nuclear staining has been reported for GATA3 and factor XIIIa (AC-1A1). We sought to determine the diagnostic utility of these nuclear stains by comparing their staining pattern to adipophilin, a consistently positive cytoplasmic stain. METHODS: Cases with the diagnosis of sebaceous hyperplasia, sebaceous adenoma, sebaceous epithelioma/sebaceoma, sebaceous carcinoma, and nonsebaceous neoplasms (basal cell carcinoma and squamous cell carcinoma) were examined. Intensity and extent of staining of the basal cells and mature sebocytes were evaluated for each stain. RESULTS: Factor XIIIa (AC-1A1) was 87.3% sensitive and 95.1% specific for all sebaceous neoplasms sand showed high inter-observer reliability. Adipophilin was 83.2% sensitive and 87.8% specific. GATA3 was the least sensitive (80.9%) and specific (75.6%) marker. When factor XIIIa was compared against composite staining of all three markers its staining was still uniquely significant (P = .0210). CONCLUSION: Factor XIIIa (AC-1A1) is a sensitive and specific nuclear marker for sebaceous differentiation. Its diagnostic utility exceeds that of adipophilin. Factor XIIIa should be included in the expanding group of immunohistochemical and special stains which can be utilized to aid in the diagnosis of sebaceous neoplasms.

Combined Melanocytic Nevus, Superficial Congenital and Deep Penetrating Types with Fibroepithelioma of Pinkus, Collision Tumor - A Case Report.

We present a case of collision tumor composed of a combined melanocytic nevus with superficial congenital and deep penetrating components and a fibroepithelioma of Pinkus on the left lumbar back of a 21-year-old male. He presented to the dermatologist for evaluation of numerous moles, and the lesion in question was described as a brown variegated papule with slightly irregular shape and irregular borders. This case is being reported as it is very unusual to see a fibroepithelioma of Pinkus in conjunction with a melanocytic lesion.

Aggressive variant of a solid pseudopapillary neoplasm: a case report and literature review.

Solid pseudopapillary neoplasm, a lesion of uncertain cellular differentiation, is an unusual tumor of the pancreas with an indolent clinical course that typically arises in young females. We report a case of solid pseudopapillary neoplasm arising in a 17-year-old adolescent girl who presented with progressive abdominal pain. The patient underwent surgical resection of an 18 × 14 × 8-cm pancreatic mass that displayed the usual histologic features of a solid pseudopapillary neoplasm in addition to prominent nuclear atypia, increased proliferative index, and extensive necrosis. These unusual histologic findings are rare and are of particular interest owing to the dramatically decreased survival time displayed in this case. Although precise pathologic criteria suggesting a high risk for aggressive behavior of solid pseudopapillary neoplasms are uncertain, recognition of the unusual pathologic features displayed in this case may be useful in the prediction of potentially more aggressive neoplasms that portend a poorer prognosis.

Usual clinical presentation of bizarre parosteal osteochondromatous proliferation (BPOP) with unusual histology.

Bizarre parosteal osteochondromatous proliferation (BPOP) or Nora's lesion is a unique, bony lesion that most often arises in the small bones of the hands and feet. The lesion was first described by Nora et al. in 1983, and documented cases have now shown the lesion to arise in the long bones, skull, maxilla and mandible. Radiographically, the bony lesion typically lacks a connection with the adjacent medullary cavity which is commonly seen with osteochondroma, the main differential diagnosis for Nora's lesion. Reported is the case of a 35-year-old male who presented to the orthopedic clinic after a non-painful mass arising on the right index finger was identified on routine physical examination. The lesion was surgically removed and sent for pathologic evaluation. Microscopic examination of the lesion revealed a disordered spindle cell proliferation and trabecular bone with no cartilaginous cap. The findings were believed to represent an osteocartilaginous neoplasm with radiographs and magnetic resonance imaging (MRI) suggestive of Nora's lesion. Thus, it was felt that the lesion fell within the overall spectrum of BPOP. The lesion is a unique entity that requires a complete history and physical exam along with radiographic and histologic analysis for proper identification. The lesion is benign but may be locally aggressive. Complete excision is the treatment of choice, and recurrence is common.

Primary cutaneous mantle cell lymphoma with blastic features: report of a rare case with special reference to staging and effectiveness of chemotherapy.

We describe a case of blastic primary cutaneous mantle cell lymphoma (MCL) in an 83-year-old male with a complex medical history. The patient presented to his primary care physician with a nodular erythematous skin eruption on his thighs. Histopathologic examination showed a diffuse lymphoid infiltrate of intermediate to large cells that involved the dermis and subcutis but spared the epidermis. Immunohistochemical staining showed expression of CD20, CD5 and cyclin-D1. The lymphoma cells were negative for CD10 and CD23. Fluorescence in situ hybridization (FISH) analysis revealed a characteristic translocation [t(11;14)(q13;q32)], which is diagnostic of MCL. Cutaneous involvement by MCL is typically secondary because of widespread disease, and primary cutaneous MCL can only be diagnosed in the absence of extracutaneous involvement. Primary cutaneous MCL is extremely rare and requires proper clinical staging. In this case, clinical staging revealed no evidence of bone marrow or peripheral blood involvement, and positron emission tomography (PET) scan revealed weak, abnormal uptake only in a few cervical lymph nodes. Because of the lack of disseminated involvement, we favor the lesion to be a primary cutaneous MCL.

Opting for Christian Science vs. surgical removal: a case report of a giant basal cell carcinoma arising on the back of a 66-year-old man.

Basal cell carcinoma is the most common form of skin cancer, with giant basal cell carcinoma comprising only 0.5 percent of all basal cell carcinomas. When a basal cell carcinoma is larger than 5 cm, it is designated as a giant basal cell carcinoma. Neglect is often a contributing factor to these lesions, and local recurrence and metastasis is not uncommon. Presented is a case of a 66-year-old man who presented with a chief complaint of increasing shortness of breath and fatigue. The patient was found to have a large 15 cm x 12 cm pedunculated tumor on his back that had been present for 10 years. The patient had forgone medical attention until presenting with a symptomatic anemia due to his belief in Christian Science, which relies on prayer and divine healing for the treatment of illness. Christian Scientists are allowed to see physicians, but they may present with advanced symptoms or disease presentations due to their beliefs. Fortunately, a computed tomography (CT) scan revealed that the tumor was confined to the skin, and biopsy revealed a basal cell carcinoma. Thus, the patient was able to undergo a wide local excision and split thickness skin graft with clear surgical margins.

Anorectal melanoma in childhood and adolescence.

The mucosal surfaces represent the third most common site of origin for melanoma, after the skin and ocular uveal tract. However, anorectal mucosal melanoma is a rare neoplasm, usually occurring in the sixth and seventh decades of life. It may often be confused clinically with other pathologic entities, such as prolapsed rectal polyps and hemorrhoids. The prognosis of anorectal melanoma is poor; this is at least in part attributable to the relatively large size that such tumors have frequently achieved at presentation, as well as their rich vascular network. In particular, anorectal melanoma in children and adolescents is extraordinarily uncommon. The authors herein report 2 examples of that tumor in 11-year-old and 19-year-old patients; one was alive and tumor-free after 6 years, whereas the other died with osseous and hepatic metastasis at the same time point. The authors emphasize the need for differential diagnostic inclusion of melanocytic malignancies when considering anorectal masses in pediatric individuals. Systematic collation and evaluation of pediatric melanomas of the anus and rectum are needed, to better define the biologic attributes of those neoplasms.