Primary extranodal histiocytic sarcoma of lumbar spine.

A 17-year-old male patient presented with lower back pain and weakness of lower limbs. On radiological investigation, a destructive bony lesion involving the third lumbar vertebra was seen associated with soft tissue extension and an extradural component. The lesion was surgically excised in view of the rapidly progressing symptoms. The histologic diagnosis was histiocytic sarcoma. Further investigations did not reveal any other lesion elsewhere. The case is being presented in view of the uncommon occurrence of a primary extranodal histiocytic sarcoma of the lumbar spine, which simulated a primary bone tumor.

Osteosarcoma of the femur mimicking Ewing sarcoma/primitive neuroectodermal tumour on biopsy and metastatic carcinoma on resection.

Osteosarcoma (OS) is known to have several morphological appearances, small cell osteosarcoma and epithelioid osteosarcoma being two well recognized patterns. The former can be mistaken for a Ewing sarcoma/primitive neuroectodermal tumour (ES/PNET), whereas the latter mimics metastatic carcinoma. Herein we present an osteosarcoma in a 17-year-old girl that was diagnosed as an ES/PNET on biopsy; however, the resected specimen revealed a very unusual morphology mimicking a metastatic carcinoma with a sex cord stromal tumour-like pattern.

Rhinosporidiosis isolated to the distal clavicle: a rare presentation clinicoradiologically mimicking a bone tumor.

Rhinosporidiosis is a chronic granulomatous disease caused by Rhinosporidium seeberi, which commonly affects young men and predominantly involves the mucous membranes of the nose, nasopharynx and eyes. Involvement of extranasal sites including bone has been reported, but rarely. We present a case of a 32-year-old farmer, who presented with a non-tender, fixed swelling over his right shoulder. Radiography and CT imaging showed an expansile, lytic, destructive lesion involving the lateral end of the right clavicle with soft tissue extension. The clinicoradiological impression was that of a primary bone tumor. Biopsy and wide excision of the lesion revealed features of rhinosporidiosis. There were no mucocutaneous lesions. Involvement of bone without associated mucocutaneous lesions is exceedingly rare in rhinosporidiosis. Involvement of the clavicle, as seen in the present case, has not been reported in the English language-peer reviewed literature, to the best of our knowledge.

Phosphaturic mesenchymal tumor with chondromyxoid fibroma-like feature: an unusual morphological appearance.

Phosphaturic mesenchymal tumor (PMT) is a rare and distinctive tumor almost always associated with oncogenic osteomalacia. This tumor is often misdiagnosed due to its widely varied histomorphological spectrum. More recently the term PMT or its variants has been used whatever the histomorphological features. Herein, we present a case of a 32-year-old woman who presented with a 2-year history of oncogenic osteomalacia. The clinical examination failed to detect any tumor. The F-18 FDG PET scan and subsequent MRI revealed a tumor in the soft tissues of the right popliteal fossa. The histological features resembled a chondromyxoid fibroma (CMF), a feature documented only in two cases so far.

Paraganglioma of the urinary bladder: a clinicopathologic spectrum of a series of 14 cases emphasizing diagnostic dilemmas.

BACKGROUND: Paraganglioma (PG) of the urinary bladder is a rare neuroendocrine neoplasm, accounting for < 0.1% of all bladder tumours. Distinction from urothelial carcinoma is imperative as management and prognosis vary markedly. In this report, we describe our experience with the histopathology of paragangliomas of the urinary bladder with emphasis on the histologic features that have led to their being misdiagnosed as conventional urothelial cancer and, most importantly, those that will help pathologists recognize this rare tumor of the bladder. MATERIALS AND METHODS: All cases of PG of urinary bladder diagnosed at our institute from 2002-2012 were retrieved and diagnosis confirmed in accordance with WHO classification. Clinical and treatment details were obtained from hospital medical records. RESULTS: Fourteen cases of PG of urinary bladder including 5 consult cases were analysed. These included 11 transurethral resections ± partial cystectomies, 2 partial cystectomies and 1 radical cystectomy. Two out of the 5 consult cases had been submitted with a diagnosis of urothelial carcinoma and 1 with that of a rhabdomyosarcoma. Age ranged from 15-84 years (median, 43 years) with a male to female ratio of 1:2.5. Presenting symptoms were haematuria, dysuria and flank pain; only 1 case had antecedent hypertension. Histologically, typical 'zellballen' (72%), diffuse (21%) and ribbon-like (7%) growth patterns amidst a richly vascularised stroma were seen. Muscularis propria invasion and necrosis was present in 72% and 21%, respectively. Substantial cautery artifacts led to misdiagnosis in the 3 erroneous cases. Tumour cells were positive for chromogranin, synaptophysin; sustentacular cells were S-100 positive. Follow up was available in 6 patients; median follow-up was 29 months (8-120 months). One patient developed distant metastasis in cervical lymph node 10 years after diagnosis; remaining were alive without evidence of disease. CONCLUSIONS: Paraganglioma of the urinary bladder is a rare tumor and may be misdiagnosed as urothelial cancer especially on TURBT, but a high index of suspicion, careful search for the characteristic histological features and supportive immunohistochemical studies should lead to a correct diagnosis.

Extranodal natural killer/T cell lymphomas with extranasal disease in non-endemic regions are disseminated or have nasal primary: a study of 84 cases from India.

Abstract We report a study of 84 extranodal natural killer/T cell lymphomas (ENKTCLs) from India to understand the disease pattern. Sixty-one patients had nasal disease and three had Waldeyer's ring tumors, while 20 had extranasal sites of presentation, namely: cervix (n = 1), oral cavity (n = 3), orbit (n = 3), liver (n = 1), ileum (n = 1), and soft tissue and lymph nodes (n = 9). Staging of patients with extranasal disease revealed that either they had disseminated disease or the nasal mass was missed during the initial staging. Extranasal presentation, performance status (PS), international prognostic index (IPI), Korean prognostic index, marrow involvement, radiotherapy and type of chemotherapy affected overall survival, while lymphopenia, performance status, radiotherapy and type of chemotherapy impacted disease-free survival. In the multivariate analysis, IPI and response to chemotherapy emerged as significant prognostic factors. Thus most patients with extranasal ENKTCL have a nasal lesion or disseminated disease and pure extranasal disease is uncommon in non-endemic regions.

Immature teratoma of the ovary: a clinicopathological study of 28 cases.

AIM: Immature teratoma (IT) of the ovary represents 1% of all ovarian cancers and 20% of malignant ovarian germ cell tumors. This retrospective study of 28 such cases aims to look at its morphological spectrum and to study the correlation of the grade and stage of the tumor with prognosis. MATERIALS AND METHODS: A retrospective study of 28 cases of IT of the ovary was done. Neuroepithelium was graded as grade I, II and III according to the standard criteria. The presence of immature mesenchyme was also looked for and similarly graded. RESULTS: The median age for the cases was 19 years and abdominal pain was the commonest symptom. Neuroepithelium was seen in 26 cases (6 were grade I, 13 were grade II, and 7 were grade III); and two showed immature mesenchymal tissue (IM) only. IM was seen in all 28 cases, but no correlation with the grade of the IT of the ovary is found. The follow up is available in 23 cases ranging from 6 months to 78 months (median 33 months). Of these, 13 were stage I, 3 were stage II and 7 were stage III ITs. Out of 23 patients, 17 patients were alive without evidence of disease recurrence during the last follow up. Adverse events in the form of death and local recurrence occurred in 6 patients. One patient died of the disease at 7 months duration from the disease onset (stage III, grade II IT). CONCLUSION: Morphological spectrum of IT of ovary is varied. Immature mesenchyme was seen in all the cases of IT of ovary and its presence should prompt a careful search for immature neuroepithelium. Stage I IT of ovary has better prognosis. Combination of surgery and chemotherapy can give longer survival even in recurrent disease.

Large cell neuroendocrine carcinoma of the endometrium: an extremely uncommon diagnosis, but worth the efforts.

Neuroendocrine carcinomas (NEC) of the female genital tract are aggressive and uncommon tumors. They usually involve the cervix and ovary, and are seen very rarely in the endometrium. The overwhelming majority of endometrial NECs are of conventional small cell type (up to 60 cases). Only seven cases of large cell type NEC of the endometrium have been reported. We report a case of large-cell neuroendocrine carcinoma (LCNEC) of the endometrium in a 70-year-old female. The case is described for its rarity and shows that a high index of suspicion can help the pathologist to use immunohistochemistry and in turn help in selection of appropriate chemotherapy.

A study of pathologic risk factors in postchemoreduced, enucleated specimens of advanced retinoblastomas in a developing country.

CONTEXT: Advanced cases of retinoblastoma are treated with chemoreduction followed by enucleation. Further adjuvant therapy is recommended in patients with known pathologic risk factors (PRFs). OBJECTIVES: To determine the PRFs in enucleated specimens after chemoreduction and their association for adverse events of recurrence, metastasis, or death. DESIGN: This was a retrospective study of 77 enucleation specimens from patients treated between January 2000 and September 2008 with prior chemoreduction that were accessioned in the pathology department of a tertiary referral cancer center with an average follow-up of 24 months. Various PRFs were noted and their association with the development of an adverse event was recorded. RESULTS: Of 77 patients, (male to female ratio, 51∶26), the incidence of overall PRF was 51.9%, and retrolaminar optic nerve invasion (32.5%), optic nerve cut margin (12.9%), massive choroidal invasion (26%), scleral invasion (23.4%), vitreous seedings (44.2%), and anterior segment invasion (20.8%). Undifferentiated tumor (>60%) was seen in 60.3% of cases (41 of 68 patients with differentiation available). Adverse event occurred in 18 of 72 patients with available follow-up (25%). Retrolaminar optic nerve invasion, optic nerve cut margin involvement, and scleral invasion were independent prognostic factors predicting the occurrence of an adverse event. Undifferentiated tumor (>60%) was a significant risk factor in univariate analysis, which is the unique feature in this study. CONCLUSIONS: Classic PRF with the addition of a predominant presence from the undifferentiated component were associated with adverse outcomes in retinoblastoma treated with anterior chemotherapy. The latter may represent chemoresistant clones and more intensive adjuvant chemotherapy may be warranted in these patients.

Multiple FDG-avid sclerosing hemangiomas mimicking pulmonary metastases in a case of soft tissue sarcoma.

Non-neoplastic lesions have been known to mimic malignancies and metastases on positron emission tomography/computed tomography. We report the rare occurrence of multiple fluorodeoxyglucose-concentrating sclerosing hemangiomas in a patient with soft tissue sarcoma mimicking lung metastases.