Extraventricular neurocytoma in a child mimicking oligodendroglioma: a diagnostic pitfall.

Extraventricular neurocytomas are rare neuronal tumours that have been included in the 2007 WHO classification as a variant of central neurocytoma. They arise outside the ventricles, usually within the cerebral hemisphere,s but also in other regions throughout the neuraxis. The morphological overlap of these tumours with oligodendroglioma often poses diagnostic difficulty. Herein, a case of extraventricular neurocytoma in a 4-year-old girl is reported that mimicked histologically oligodendroglioma. The authors describe the clinicopathological features of this rare entity with special emphasis on differential diagnosis.

[Epidemiology of extrapulmonary hydatid cysts: 265 Tunisian cases]. / Epidémiologie des kystes hydatiques extrapulmonaires : 265 cas en Tunisie.

AIM OF STUDY: The authors wanted to analyze the epidemiological features of extrapulmonary hydatid cysts and compare their results with those reported in literature. METHODS: Two hundred and sixty-five cases of extrapulmonary hydatid cysts collected from 1990 to 2007 were retrospectively studied. RESULTS: One hundred and one male and 164 female patients (sex ratio M/F=0.61 mean age 38.7 years) were included. In our series, hydatid cysts involved mainly the kidney (24.1%), the central nervous system (22.6%), the liver (19.6%) and the spleen (11.3%). CONCLUSION: Contrary to published data, our results show that hydatid cysts of the kidney and of the central nervous system are more frequent than hepatic location which ranks 3rd. Such unusual results may be due to a selection bias.

Cutaneous gamma-delta T-cell lymphoma arising in the setting of Behcet's disease.

Cutaneous gamma-delta T-cell lymphoma (CGD-TCL) is an uncommon lymphoma composed of a clonal proliferation of mature activated gamma-delta T-cells expressing a cytotoxic phenotype. Malignant lymphoma is rarely associated with Behcet's disease, as only 12 cases have been reported in the literature, including a case of cutaneous T-cell lymphoma. In this report, the authors present a new case of CGD-TCL emerging in the course of Behcet's disease in a 40-year-old man. Diagnosis of CGD-TCL was established based on the combination of clinical, histological, immunophenotypical and molecular findings. Through a review of the current literature, the authors analyse the unique clinicopathological, molecular and immunohistochemical features of this rare cutaneous lymphoma.

Extragastrointestinal stromal tumor of the urinary wall bladder: case report and review of the literature.

Most mesenchymal tumours of the gastrointestinal tract are now referred to as gastrointestinal stromal tumours (GISTs). These tumours typically express c-kit (CD117) and CD34; 30-50% are (often focally) positive for alpha-smooth muscle actin, and all are negative for desmin and S100 protein. Recently, mutations in exon 11 of the c-kit gene have been identified as a molecular genetic marker for the subset of GISTs. In this report, we describe a mesenchymal tumour removed from the pelvic cavity of a 34-year-old man. The tumour was strongly attached to the external wall of the urinary bladder. The neoplasm grossly resembled a leiomyoma, and was histologically composed of sheets of spindle cells with a dense collagenous background. The mitotic activity was low (less then 1 per 50 high-power fields). Immunohistochemically, tumour cells were negative for alpha-smooth muscle actin and desmin and positive for CD117 and CD34. This case illustrates that tumours which are phenotypically and genotypically similar to GISTs may present in sites other than the tubular gastrointestinal tract.

Renal epithelioid angiomyolipoma: a case report and literature review.

BACKGROUND: Renal epithelioid angiomyolipoma is a recently recognized variant of angiomyolipoma, closely simulating renal cell carcinoma both clinically and histologically. Only a relatively small number of cases of epithelioid angiomyolipoma of the kidney have been reported. AIM: To highlight clinicopathological features of this rare tumour. OBSERVATION: We report herein a new case of renal epithelioid angiomyolipoma in a 38-year-old male with no stigmata of tuberous sclerosis. The tumour was composed of diffuse sheets of epithelioid cells, small numbers of adipocytes and occasional blood vessels. Immunohistochemically, neoplastic cells were immunoreactive for HMB-45, but negative for cytokeratin. The patient showed no evidence of recurrence or metastatic disease one year after radical nephrectomy. CONCLUSIONS: Epithelioid angiomyolipoma may be locally aggressive and can metastasise; therefore, long-term post-operative follow-up is mandatory.

Hemangiopericytoma in the central nervous system. A study of eight cases.

Most hemangiopericytomas (HPC) are located in the musculoskeletal system and the skin, while the location in the central nervous system (CNS) is rare. The latter represents 2 to 4% in large series of meningeal tumors, thus accounting for less than 1% of all CNS tumors. In the central nervous system, tumors with a hemangiopericytomatous histolopathological pattern can be either hemangiopericytomas or solitary fibrous tumors. CNS-HPCs have a relentless tendency for local recurrence and metastases outside the CNS. Metastasis can also appear many years after adequate treatment of the primary tumor. We present a pathological study of eight patients with CNS-HPC and compare our results with corresponding published data. The CNS-HPC group consisted of three males and five females with a mean age of 36.75 years. The tumors were supratentorial in four cases, infratentorial in two cases, tentorial in one case and located in the spinal cord in the last one. Histologically, CNS-HPCs were similar to their soft tissue counterparts. One case demonstrated increased cellularity, marked nuclear hyperchromasia and marked cellular pleomorphism with infiltration of the cerebellum. All patients underwent surgery with gross-total resection in all cases. No patients received postoperative radiation therapy. Only four patients recurred locally after six, seven and eight months, and five years. Our study presents the pathological features of CNS-HPC as a distinct entity from both meningioma and solitary fibrous tumors. A comparative review of literature with our results is discussed.

Paratesticular angiomyofibroblastoma: case report and review of the literature.

Angiomyofibroblastoma is a rare, benign, mesenchymal tumour occurring mainly in the female genital tract, and more rarely, in males. We present a new case of angiomyofibroblastoma arising in the left inguinal region of an 83-year-old man. The tumour was well circumscribed and measured 60 mm in maximum dimension. On microscopic examination, the tumour was composed of small spindle cells without atypia within a fibrous and myxoid stroma where scattered mononuclear inflammatory cells were found around the capillaries of the stroma. Immunohistochemical studies showed positive staining of tumour cells for vimentin, desmin, smooth muscle actin and CD34, and negative staining for PS100 and oestrogen and progesterone receptors. These histological findings are consistent with angiomyofibroblastoma. The patient was followed up for 4 years without recurrence.

Canalicular adenoma of buccal mucosa.

Canalicular adenoma is a benign tumor which comprises 1% of salivary gland neoplasms and 4% of minor salivary gland tumors. It occurs in the upper lip mucosa in about 90% of cases. The next most common location is the buccal mucosa (9.5% of tumors). We present herein a new case of canalicular adenoma of buccal mucosa involving a 74-year-old man. He was suffering of a slowly growing and painless nodule of the right buccal mucosa. The treatment was surgery and histological findings were consistent with the diagnosis of canalicular adenoma. No recurrence was noted one year later.

Primary central nervous system malignant melanoma: report of 5 cases.

Primary melanocytic neoplasms of the central nervous system consist of a spectrum of lesions ranging from well-differentiated melanocytoma to its overtly malignant counterpart, melanoma. Clinicopathologic features of 5 cases of primary central nervous system malignant melanoma were studied to define histologic appearances, diagnostic criteria, and the clinical behavior of lesions along this spectrum. There were three women and two men (mean age was 35 years) with symptoms of increased intracranial pressure. Radiological findings showed a solitary intra parenchymal lesion with variable enhancement after gadolinium administration. All patients underwent surgical treatment. Histologic examination revealed primary melanoma.

[Subcutaneous hydatid cyst. Case report of an exceptional location]. / Kyste hydatique sous-cutané: à propos d'une localisation exceptionnelle.

Primary subcutaneous cyst hydatid disease is an exceptional entity. We report a new case involving a 70-year-old woman hospitalized for a subcutaneous mass in the hypogastric area with no local inflammatory signs. Radiological examination was consistent with a partially calcified subcutaneous cyst in the hypogastric area. Complete surgical resection of the mass was performed with uneventful postoperative recovery. Histopathological examination of the surgical specimen demonstrated multivesicular hydatid cyst.

Desmoplastic small round cell tumor of the abdomen. Report of two cases.

Desmoplastic small round cell tumor (DSRCT) is a rare clinicopathological entity individualized in 1989. Its etiopathogenesis is still unknown, and diagnosis can be achieved only by immunohistochemistry and cytogenetic studies. The objective of this work is to report two new cases of DSRCT and to review the literature to clarify its epidemiological, clinical and pathological aspects.

Intracranial medulloepithelioma. A case report and review of the literature.

Medulloepithelioma is a rare primitive neuroectodermal tumour of the central nervous system usually developing in childhood, displaying highly malignant behaviour, with early progression or recurrence. The Authors report a new case of intracranial medulloepithelioma removed from the right cerebellar hemisphere of a 13-year-old boy who showed unspecific signs of intracranial hypertension. Based on a review of the thirty seven cases reported in the literature, they analyse the clinical, histological, immunohistochemical, ultrastructural and therapeutic features of this rare nervous system tumour.

Huge cystic lymphangioma of the adrenal gland. A case report and review of the literature.

Cystic lymphangioma of the adrenal gland is a rare and benign lesion, most often found incidentally during abdominal imaging studies, abdominal surgery or at autopsy. Preoperative diagnosis is difficult. Diagnosis is histological. We report a 22-year-old female presented with abdominal pain. Laboratory findings were normal. Radiological examination revealed a 35 cm left adrenal cyst. The cyst was resected and the diagnosis of cystic lymphangioma of the adrenal gland was histologically made. In presenting this case and reviewing the literature, we seek to make better known the epidemiologic, the clinicopathologic presentation and the prognosis of this rare entity.

[Benign sacrococcygeal teratoma in an adult]. / Tératome sacrococcygien bénin de l'adulte.

Sacrococcygeal teratomas are rare congenital tumors generally discovered at birth. Exceptionally these tumors are observed in adults. Radical resection must be performed to avoid potentially malignant recurrence even if the primary lesion was benign. We report a case of a benign sacroccygeal teratoma diagnosed in a 25-year-old male and discuss clinical features, pathological considerations and treatment.

[Subcutaneous phaeomycotic cyst of the ankle]. / Kyste phaeomycotique sous-cutané de la cheville.

Phaeohyphomycosis is a rare mycotic opportunist disease witch usually affects immunodepressed patients. Infection follows a traumatic inoculation of fungi into the skin with formation of a subcutaneous cyst. We report the case of a 20-year-old woman presenting with a subcutaneous, painless, and recurrent cystic lesion on the right ankle for 9 years. A surgical excision was performed. Histopathologic examination showed a granuloma with central abscess surrounded by a thick fibrous tissue. After staining with PAS, septate hyphae and spores were found in the granuloma, consistent with a phaeomycotic cyst.

[Hydatid cyst of the posterior fossa]. / Kyste hydatique de la fosse postérieure.

Hydatidosis is an endemic affection in Tunisia. Cerebral echinococcosis is a relatively rare entity accounting for only 1-2% of all hydatid cysts in humans. Extradural hydatid cyst of the posterior fossa is a very uncommon site for the disease. We report the case of a four-year-old child admitted for high intracranial pressure. Brain CT scan showed an extradural posterior fossa cyst without enhancement after contrast medium injection. Operative finding revealed a hydatid cyst. The histological examination of the tissue sample confirmed the diagnosis. The patient was given albendazole post operatively. She feels well six months later.

[Chordoid meningioma. Two cases]. / Le méningiome chordoïde. A propos de deux cas.

Chordoid meningioma is an uncommon histopathological variant of meningioma frequently confused with chordoma. Recurrence is not uncommon. The aim of our study is to present the clinical and pathological characteristics of this entity and a review of the literature. We report two cases of chordoid meningioma occurring in two women aged 47 and 63 years. Both women presented neurological signs without systemic disease. Radiological findings were temporoparietal and temporofrontal lesions with intense enhancement after contrast injection. Complete surgical resection was performed. Histopathologic findings were consistent with chordoid meningioma.

Primary cutaneous leiomyosarcoma: a histological and immunohistochemical study of 4 cases.

Primary cutaneous leiomyosarcoma is an uncommon malignant neoplasm with a predilection for the lower extremities. A retrospective study of 4 cases was undertaken to analyse the clinicopathological characteristics and immunohistochemical profile of these neoplasms with emphasis on prognosis. Two male and 2 female patients aged between 49 and 80 years presented with painless tumours involving the lower lip, the chin, the scrotum and the shoulder. Histological examination of the initial biopsy specimen established a diagnosis of cutaneous leiomyosarcoma. All cases co-expressed smooth muscle actin and vimentin regardless of primary tumour site. Wide surgical excision of the tumour was performed in only 3 cases, and the remaining patient refused further treatment. Of the patients undergoing surgical intervention, local recurrence occurred in one case. No metastases were observed. Long-term follow-up of patients with cutaneous leiomyosarcoma is mandatory to detect local recurrence and distant metastases that can occur even years after the initial excision.