Background: Epithelioid sarcoma is a rare malignancy that presents diagnostic difficulties.

Cases: We report three cases of epithelioid sarcoma with different presentations and clinical course. One patient had a classicaltype epithelioid sarcoma while rest two suffered from the rarer proximal-type. All three underwent surgical excision while two of them also had postoperative adjuvant therapy. The diagnostic challenges and the final outcome has been discussed in detail.

Conclusion: The diagnosis of epithelioid sarcoma needs a high index of clinical suspicion and immunohistochemistry is extremely valuable. Adequacy of index surgery affects the ultimate prognosis.

Omental extragastrointestinal stromal tumors are rare neoplasms. We present a case of an elderly woman who was found to have a large solid and cystic pelvic mass of presumed ovarian origin with associated omental neovascularity. Histopathologic examination showed a mixed spindled and epithelioid tumor which was essentially negative for c-KIT and positive for smooth muscle markers by immunohistochemistry. A next generation sequencing panel was performed, analyzing the patient’s tumor for actionable mutations in 50 genes commonly associated with human cancers. Identification of a point mutation in PDGFRA enabled accurate diagnosis and provided an option for targeted therapy for this rare tumor.

Warty carcinoma of the uterine cervix is a very rare and specific variant of invasive squamous cell carcinoma, usually described as a hybrid of the features of both condyloma acuminatum and invasive squamous cell carcinoma. The diagnostic pitfalls of this lesion are: 1) the bland appearance of cytomorphology, 2) distinct koilocytotic atypia, and 3) p16 negativity. A case of warty carcinoma with a fungating mass on the uterine cervix of a 75-year-old woman is presented. The original diagnosis by punch biopsy was atypical squamous cells, undetermined for malignancy, adjunct with p16 negativity. The subsequent radical hysterectomy showed a protruding mass (5.7 cm in horizontal dimension) of the uterine cervix. Light microscopy revealed a protruding mass composed of exophytic papillae and inverted nests along the endocervical glands. There were multiple micro-invasive foci (＜ 1 mm) of tongue like projections at the nest base and slight involvement of the upper vagina and endometrial surface. The p16 immunohistochemical staining yielded negative results. The results of the HPV DNA chip test from paraffin-embedded tissue were 6 (low risk, +++) and 42 (low risk, +). The Ki-67 proliferation index was approximately 20%. The invasive foci and patient’s age were the determining differential factors for malignancy rather than benign condylomatous lesion.

A solitary cystic lesion in the abdominal wall is generally benign, such as an omental cyst, mesenteric cyst, enteric duplication cyst, cystic mesothelioma, or skin appendage tumor. Furthermore, most malignancies in the urachal remnant are intraperitoneal lesions, and generally develop on the anterior aspect of the bladder dome. Moreover, most urachal glandular malignant neoplasms are the mucinous cystic type. We report a cystic urachal adenocarcinoma that presented as an abdominal wall cystic lesion. A 42-year-old woman was admitted to Kangwon National University Hospital for a 5-cm palpable abdominal wall mass. Conservative surgical excision was performed with subsequent histological and immunohistochemical evaluations, but only a few non-mucinous invasive glands and finger-like growths were noted. During a 2-year period, the tumor recurred several times along the urachal tract and metastasized to the regional lymph nodes. Despite receiving chemotherapy, the patient died 2 years after the first surgery.

Hemophagocytic lymphohistiocytosis (HLH) is a clinical syndrome that can be inherited or acquired. Herein, we report a case of HLH and pulmonary alveolar proteinosis (PAP) in the setting of lysinuric protein intolerance (LPI) in a male toddler who presented with prolonged fever, respiratory distress, and failure to thrive. On histologic examination, hemophagocytosis was observed in lymph node, bone marrow sections and aspirates. Lung wedge resection was consistent with PAP. LPI was confirmed with genetic sequencing which revealed compound heterozygous mutations in the SLC7A7 gene. LPI is a rare inborn error of metabolism and is not widely known beyond the pediatric group. Though the association of LPI with HLH has been previously described, we believe this is the first reported case of HLH and PAP associated LPI with histopathological correlation. Early recognition of HLH is critical to successful treatment and LPI should be considered in any young infant who presents with HLH- and PAP-related symptoms.

Digital Papillary Adenocarcinoma (DPA) is a very rare neoplasm of sweat glands, with approximately 100 cases in the literature. We present a rare case of DPA of the ankle in a 66-year-old African American man. DPA has a high potential for metastases to the lung and lymph nodes, and initial treatment often entails wide excision or complete digital amputation. DPA typically presents as a painless lesion or mass of the distal digits of the hands or feet. With the limited available literature regarding this malignancy, there is no standard approach to treatment. Wide excisional margins with sentinel lymph node mapping and biopsy are based on extrapolation for other tumors. In the following report, we discuss a representative case and the current literature on the presentation, treatment and pathology of this rare neoplasm.