Non psammomatous melanocytic schwannoma presenting as a subcutaneous nodule: A rare presentation of a rare lesion.

Melanocytic schwannoma (MS) is an extremely rare soft tissue tumor accounting for less than 1% of all primitive nerve sheath tumors, with a predilection for spinal nerve involvement. To date, only 20 cases of cutaneous/subcutaneous MS have been described in literature. Here, we describe a case of MS presenting as a subcutaneous nodule in a 22-year-old male in right thigh. On examination, the nodule measured 2.5 × 2.0 × 1.5 cm with overlying skin showing a bluish hue and an ulcer. With a preoperative diagnosis of hemangioma, the patient was taken up for wide local excision and was diagnosed as a case of non psammomatous melanocytic schwannoma based on clinical, histological, and immunohistochemical studies. Immunohistochemistry revealed positivity with S-100, HMB-45, and Melan A with pericellular Laminin positivity. Carney's syndrome was ruled out. MS needs to be differentiated from other pigmented lesions like pigmented neurofibroma, Bednar tumor, cellular blue neavus, and especially malignant melanoma, which has an obvious ominous prognosis. Since MS can show unpredictable behavior especially in absence of overt malignant features, a long term follow up with or without radiotherapy is recommended.

Papillary squamotransitional cell carcinoma of the uterine cervix: A histomorphological and immunohistochemical study of nine cases.

BACKGROUND: Papillary squamotransitional cell carcinoma (PSCC) is a distinctive subcategory of squamous cell carcinoma of the uterine cervix. It has a propensity for local recurrence and late metastasis. Histologically, it can be misinterpreted as transitional cell carcinoma, or other papillary lesions of the cervix including squamous papilloma, verrucous carcinoma or cervical intraepithelial neoplasia grade 3 with papillary configuration. MATERIALS AND METHODS: Nine cases of PSCC of the uterine cervix were diagnosed on a cervical biopsy specimen on routine hematoxylin and eosin (H and E) stained sections. Their clinic-morphological features were analyzed. The cases were further evaluated immunohistochemically by cytokeratin 7 (CK7), cytokeratin 20 (CK20), p53 and Ki-67. RESULTS: The patients ranged in age from 35 years to 75 years; with abnormal uterine bleeding being the most common clinical presentation. All the cases showed papillary architecture with fibrovascular cores lined by multilayered atypical epithelium. Three cell types were observed: Clear, intermediate and basaloid. Stromal invasion was seen in five cases, whereas in the remaining four cases, the biopsy specimen was too superficial to definitely assess invasion. Immunohistochemically, eight cases were CK7(+)/CK20(-) and one case was CK7(-)/CK20(-). All nine cases showed nuclear accumulation of mutant p53. Moderate and high proliferative activity was observed in two and seven cases, respectively. Five of patients for whom follow-up information was available underwent radical hysterectomy and two of them were disease free 18 months following treatment. CONCLUSION: PSCC of the uterine cervix are a clinicomorphologically distinct group of cervical lesions that display a morphologic spectrum. They are potentially aggressive malignant tumors that should be distinguished from transitional cell carcinoma and other papillary lesions of the uterine cervix.

Angiomatous leiomyoma of the urachus: A rare entity masquerading as extraluminal gastrointestinal stromal tumor.

The urachus is a vestigial structure located between the dome of the bladder and the umbilicus, which results from the involution of the allantoic duct and the cloaca. Persistence of an embryonic urachal remnant can cause various problems during childhood and young adulthood. Urachal leiomyoma is a rare entity with very few cases being reported in literature. It can be misdiagnosed and confused with a wide spectrum of intra-abdominal or pelvic disorders. We hereby report a case of angiomatous leiomyoma originating from the urachal remnant in a 45-year-old lady, masquerading as extraluminal gastrointestinal stromal tumor. Understanding the embryological basis of these urachal disorders and their imaging features coupled with histopathological examination is crucial for the correct diagnosis and management. Pathological diagnosis is required to optimize the surgical approach and preclude unnecessary radical surgery.

Malignant peripheral nerve sheath tumor of facial nerve: Presenting as parotid mass.

Malignant peripheral nerve sheath tumor (MPNST) is very uncommon tumor of parotid gland and it is an uncommon spindle cell sarcoma accounting for approximately 5% of all soft-tissue sarcoma. There is strong association between MPNSTs and neurofibromatosis (NF-1) and previous irradiation. Structural abnormality of chromosome 17 is associated with NF-1 and so MPNST. We present a case of a 78-year-old male presenting with slowly growing parotid mass who underwent tumor resection.

Primary adrenal leiomyosarcoma: a case report with immunohistochemical study and review of literature.

Primary adrenal mesenchymal tumors are exceptionally rare. Diagnosis is based entirely on histological and immunohistochemical evaluation which is indispensable not only for determining tumor type but also for predicting biological behavior. We report a rare case of primary leiomyosarcoma of the left adrenal gland, in a 60 year old woman who presented with flank pain. Computed tomography revealed a well defined left adrenal tumor which was surgically resected. Histological examination of the tumor showed malignant spindle cells in interlacing fascicles and whorls. Nuclear pleomorphism, tumor giant cells and abnormal mitotic figures were seen. On immunohistochemistry, the tumor cells showed reactivity for smooth muscle actin, vimentin and desmin; and were negative for cytokeratin, S100 protein, CD117 and HMB-45. A diagnosis of primary adrenal leiomyosarcoma was offered. Postoperative recovery of the patient was uneventful and the patient was symptom free with no evidence of tumor metastasis or recurrence 21 months after surgery.

Extra-osseous tenosynovial chondromatosis of the middle finger: a case report.

Extra-osseous tenosynovial chondromatosis is rare and has a high rate of local recurrence. We report a 23-year-old man who presented with a 6-month history of pain and swelling of the right middle finger and painful limitation of the ring finger flexion secondary to this condition. Surgical exploration revealed multiple loose bodies of varying size arising from the flexor tendon sheath. Histopathological examination revealed mature chondroid tissue and focal calcification. After 2 years of follow-up, the patient had achieved an excellent functional recovery and showed no evidence of recurrence.

Incidental cystic endocrine tumor of the pancreas: a case report with immunohistochemical study.

A large cystic lesion in the pancreatic tail was found incidentally in a 20-year-old female during laparoscopic cholecystectomy. Pre-operative work up had revealed calculi in gall bladder and in addition, a cystic lesion in pancreas suggesting the possibility of a pseudocyst. A laparoscopic enucleation of the cyst was performed along with the removal of gallbladder. Microscopic examination of the resected specimen revealed a pancreatic cystic endocrine tumor; however, this tumor had produced no symptoms. Immunohistochemical studies of the tumor cells showed positivity for neuron-specific enolase, chromogranin A, and synaptophysin indicating their neuroendocrine nature. Prognostic markers (CK19, CD10 and Ki67) indicated good prognosis. Although endocrine tumors of the pancreas are usually solid, cystic change occurs only rarely and such tumors should be considered in the differential diagnosis of patients who have a cystic lesion in the pancreas in view of their rare transformation into a malignant tumor.

Massive abdominal wall endometriosis masquerading as desmoid tumour.

Endometriosis is a common gynaecological condition that usually presents as an abdominal lump. It can be a diagnostic dilemma and should be considered as a differential diagnosis for lumps in the abdomen in females. We discuss a case of abdominal wall endometriosis following caesarean section, which was misdiagnosed as a desmoid tumour.

Congenital cystic adenomatoid malformation in an adolescent: an unusual presentation with pleural effusion and pneumatocele.

Congenital cystic adenomatoid malformation (CCAM) encompasses a continuum of hamartomatous cystic lung lesions characterised by the presence of abnormal bronchiolar structures of varying sizes or distribution. The CCAM is a disorder of infancy with majority of the cases being diagnosed within the first two years of life. We describe CCAM in a 13-year-old girl complaining of recurrent lower respiratory tract infections since infancy who presented with post-infectious pneumatocele with loculated pleural effusion, and suspected abscess formation and had undergone resection.

Low-grade malignant proliferating pilar tumor simulating a squamous-cell carcinoma in an elderly female: a case report and immunohistochemical study.

A 65-year-old lady presented with an ulcerated lesion over the occipital region of nine-year duration, an incisional biopsy of which was reported as squamous-cell carcinoma. A wide local excision was performed and the tissue was sent for histopathological examination which revealed a low-grade malignant pilar tumor. Focal invasion and atypia were noted. Immunohistochemical (IHC) analysis revealed positivity for CD34 and calretinin immunomarkers favoring outer root sheath origin. Ki67 immunostains revealed a relatively low immunoreactivity indicating the low-grade nature of the tumor; however, p53 immunostain showed strong diffuse nuclear staining confirming the malignant nature of the tumor. Proliferating pilartumors (PPT) are rare tumors and less than 100 well-documented cases of malignant PPT have been reported so far in the literature. These tumors have been recently classified into benign, low- and high-grade malignant tumors and statistically significant difference was found in their biological behavior. However, we propose that IHC can be of immense value in assisting the subtyping of the tumor, so that the behavior and role of adjuvant therapy can be validated in future studies.

Subcutaneous Zygomycosis Due to Basidiobolus ranarum: A Case Report from Maharastra, India.

Entomophthoromycosis is a rare entity. We hereby report a case of entomophthoromycosis in a three-year-old Asian child who presented with a painless, nontender, rapidly increasing large swelling on the thigh of six months duration, which was initially misdiagnosed as a soft tissue tumor and resected. The cause of misleading diagnosis was rapid growth of the lesion in a short duration of time, indicating the possibility of a tumor. Histopathological examination revealed an inflammatory lesion with aseptate fungal hyphae and the characteristic Splendore-Hoeppli phenomenon. Microbiological examination identified the fungus as Basidiobolus ranarum. Complete excision of the lesion followed by antifungal therapy was associated with complete recovery. Entomophthoromycosis should be considered early when children from endemic areas present with unusual, rapid-growing lesions of the subcutaneous region. In order to emphasize tumor-like presentation of zygomycosis, we are presenting this case.