Malignant proliferating trichilemmal cyst of the scalp: histological aspects and nosology.

BACKGROUND: Malignant proliferating trichilemmal cyst is a rare tumour usually located on the scalp of elderly women. About 40 cases of malignant proliferating trichilemmal tumour have been documented. CASE REPORT: We report a case of a malignant proliferating trichilemmal cyst of the scalp in a 57-year-old woman. On the vertex she had a voluminous vegetated and multinodular tumour measuring 7 x 5 cm with spontaneous and abundant bleeding, and another lesion of the scalp corresponding to a trichilemmal cyst. Based on histopathological findings, the case was diagnosed as malignant proliferating trichilemmal cyst. CONCLUSION: Diagnostic, clinicoprognostic and histological features of this tumour are discussed. Treatment is not yet standardized given its rarity.

Rectal leiomyosarcoma: report on two cases and a practical approach to differential diagnosis.

Rectal leiomyosarcoma is an uncommon malignancy. Herein, we describe the clinicopathological features and biological behaviour of these tumours, and provide a practical approach to differential diagnosis, particularly with gastrointestinal stromal tumours (GIST). We report two cases in elderly men. In the first, the lesion was 2 cm from the anal sphincter, while it was located in the rectal ampulla in the second case. Histologically, both tumours were characterized by pleiomorphic, large spindle cells, presenting numerous mitoses and marked nuclear atypia. Immunohistochemical analysis showed that tumour cells coexpressed both actin and desmin, whereas CD117 and S100 protein were negative. The final diagnosis was leiomyosarcoma. One of the patients died of pulmonary metastasis within six months. The second patient had bone metastasis, but was lost to follow up. This report underlines the potential diagnostic problems raised by rectal leiomyosarcoma and emphasizes the role of immunohistochemistry in achieving correct diagnosis, which has important clinical, therapeutic and prognostic consequences.

[Complicated sigmoid tumor: perforated amebiasis]. / Une tumeur sigmoïdienne compliquée: amoebome perforé.

Amoeboma is an inflammatory mass of the colon. It can be an inaugural symptom and thus pose the problem of differential diagnosis with colon cancer. The purpose of this report is to describe the case of a 43-year-old patient who presented with acute abdomen. Physical examination revealed a perforated circumferential mass in the sigmoid colon. Based on a presumptive diagnosis of colonic cancer complicated by perforation, segmental colectomy was performed. Histological examination of the surgical specimen demonstrated colonic amoeboma. The patient was treated using metronidazole. Although rare, amoeboma must be considered in differential diagnosis of cancer of any colonic mass.

Bilateral elastofibroma dorsi. A case report and review of the literature.

Elastofibroma is a rare benign soft tissue lesion, typically located deep under the lower pole of the scapula. It is characterized by a fibrous and adipose tissue proliferation and most frequently affects older females. Its characteristic location and its specific aspect in imaging studies most often provides the diagnosis following an incidental discovery. Nevertheless, anatomic and pathologic confirmation is necessary to formally rule out a malignant tumor diagnosis. We report a 66-year-old woman original observation; this lady's occupation involved a number of strenuous manual activities; she consulted for chronic pain related to a left subscapular mass. MRI demonstrated, in fact, two symmetrical tumor masses under each scapula. The only symptomatic lesion was surgically excised.

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.