Benign myoepithelioma of the lung - a case report and review of the literature.

INTRODUCTION: Benign myoepithelioma is extremely rare in the lung, to the best of our knowledge; only five cases have been reported in the literature. CASE REPORT: An 18-years woman complained from tiredness and fever during four months. Laboratory findings and fibroscopies were normal. CT of the thorax demonstrated a nodule in the left segment of the Fowler. Left inferior lobectomy was performed comporting a firm nodule of 25 mm, lifting the bronchial mucous membrane. Histologically, there was a proliferation of small cells of a plasmocytoid-type, with a predominantly whorled pattern. No mitotic activity or necrosis was seen in the tumor. Immuhistochemically, the tumor cells positive for smooth muscle actin, vimentine, and S100 protein. They were negatives for cytokeratine, chromogranine and HMB45. The diagnosis of benign myoepithelioma of the lung is so confirmed. The patient recovered well at 6 months follow-up. CONCLUSION: Benign myoepithelioma is a rare pulmonary neoplasm distinct from pleomorphic adenoma, which should be considered in the differential diagnosis of lung nodules.

Solitary fibrous tumour of the central nervous system: pathological study of eight cases and review of the literature.

AIMS: Solitary fibrous tumours (SFT) of the central nervous system are rare neoplasms that usually present as dura-based masses and clinically resemble meningiomas. Histologically, they can be similar to haemangiopericytoma or fibrous meningioma. We present herewith a pathological study of eight patients with SFT and compare our results with the published data. METHODS: All tumours diagnosed as SFT over a period of 15 years were retrieved from the files of La Rabta Hospital Department of Pathology, Tunisia. Routine histological sections were prepared from formalin-fixed, paraffin-embedded specimens. Immunohistochemical analysis was performed using antibodies raised against vimentin, CD34, CD99, Bcl-2 and MIB-1. RESULTS: The SFT group consisted of four males and four females with a mean age of 44 years. The tumours were supratentorial in six cases, tentorial in one case and located in the lateral right ventricle in the last case. All patients underwent surgery as initial treatment. Histologically, SFT were similar to their soft tissue counterparts. Two cases demonstrated increased cellularity, marked nuclear hyperchromasia and marked cellular pleomorphism. Only the later two cases recurred after 6 months of follow-up. CONCLUSION: Little is known about the biological behaviour of SFT, although most seem amenable to total resection.

[Parotid basal cell adenoma of membranous type]. / Adenome a cellules basales de type membraneux de la parotide.

INTRODUCTION: Basal cell adenoma (BCA) is a rare benign neoplasm characterized by the basaloid appearance of the tumour cells and the lack of myxo-chondroid stromal component present in pleomorphic adenoma. AIM: We report a case of basal cell adenoma of membranous type, highly suspected of malignancy because of the presence of mediastinal lymph nodes and pulmonary nodules which finally were related to an associated sarcoidosis. OBSERVATION: Our patient was an 80-year-old woman who presented a swelling of the right parotid two years ago. The clinical examination revealed a solid, indolent and mobile mass. A chest radiography noted mediastinal lymph nodes. The CT-scan confirmed the presence of mediastinal and tracheal lymph nodes with pulmonary nodules. So the diagnosis of metastatic malignant salivary gland tumor was suspected. Finally, the histological examination concluded to a basal cell adenoma of membranous type with sarcoidosis granulomas in the parotid and in the lymph nodes. CONCLUSION: The BCA is a benign tumor located generally in the parotid gland. When the malignancy is suspected, like in our case, this tumor must be differentiated from the basal cell adenocarcinoma using histological criteria.

[Solid pseudopapillary tumors of the pancreas: a pediatric case report]. / Tumeur solide pseudopapllaire du pancreas: a propos d'une observation pediatrique.

BACKGROUND: Solid pseudopapillary tumors of the pancreas are extremely rare and mostly seen in young females. It is often diagnosed incidentally or during investigations of gastrointestinal complaints. AIM: Report of a pediatric case of this tumor. CASE REPORT: We report the case of a 15-year old teenager who presented with painful abdominal tumefaction. Imaging findings were a 12 cm solid and cystic mass originating from the tail of the pancreas. A distal pancreatectomy with splenectomy was performed. Pathologic examination concluded to solid pseudopapillary tumor. Evolution was favorable with no recurrence 18 months after surgery. CONCLUSION: Histological examination confirms the diagnosis and allows, with the help of immunohistochemical study, to rule out some differential diagnoses such as pancreatoblastoma, acinar tumors and endocrine tumors. Prognosis of solid pseudopapillary tumors of the pancreas is excellent after radical resection and recurrences are rarely seen.