Primary leiomyosarcoma of the anterior mediastinum.

Primary mediastinal leiomyosarcoma are extremely rare tumors, which develop from smooth muscle, usually in the esophagus or main vessels. Very few cases have been reported in the literature and only two of these developed from small vessels in the soft tissue of the anterior mediastinum. We report on a 45-year-old man who presented with a huge anterior mediastinal tumor. The tumor was surgically removed with right thoracotomy and the diagnosis of well-differentiated leiomyosarcoma was established. It probably originated from the anterior mediastinal tissue, so at operation a continuity was not found between the tumor and neighboring structures. This rare and interesting histopathology is discussed and the literature is reviewed.     

Osteoclast-like giant cell tumor of the pancreas associated with cystadenocarcinoma

Osteoclast-like giant cell tumor is a very rare type of pancreatic malignancy, and no more than 20 cases have been reported in the English literatures. A case of this tumor associated with cystadenocarcinoma is reported. This giant cell is undistinguishable on light microscopy from osteoclast of bone and correct diagnosis of this unusual tumor is important because of its relatively poor prognosis.     

Rhabdomyosarcoma of the spermatic cord. A case report with review of the literature

Rhabdomyosarcoma is a rare malignant tumor that may occur in the spermatic cord in childhood. So far, 62 cases have been reported in the English literature. We describe a case of embryonal rhabdomyosarcoma of the spermatic cord in a 15-year-old boy, detailing clinical history, light microscopy, immunohistochemistry and treatment. In order to unquestionably demonstrate the myogenic differentiation of the neoplasm, it was decided to use a monoclonal antibody against MyoD1. The nuclear positivity of this phosphoprotein in the tumor cells confirmed the diagnosis of embryonal rhabdomyosarcoma. Consequently, the patient was treated with right radical orchiectomy and retroperitoneal lymph node dissection (RPLND). The latter is usually required because of the high incidence (more than 50% of cases) of positive retroperitoneal nodes, whereas subsequent adjuvant therapy is occasionally necessary. In the present case, we decided for a careful follow-up on the basis of the small size of the tumor and the absence of metastasis at diagnosis. The patient is alive and free of disease 12 months after surgery.     

Primary intracranial rhabdomyosarcoma

Primary intracranial rhabdomyosarcoma is rare. Twenty-one cases with dismal outcomes have been reported. We add five children with this disease treated between 1977 and 1982. Their therapy consisted of surgical resection, craniospinal irradiation, and intravenous-intrathecal chemotherapy. Two children have recovered, 21 and 67 months after diagnosis; the last is the longest survival reported in the literature. Two succumbed to tumor recurrence, and one died due to pulmonary embolism. The posterior fossa was invariably a site of tumor at presentation. Diagnosis with light microscopy can be elusive; electron microscopic and immunohistochemical evaluation are necessary to confirm the pathological condition. This is essential so that early, aggressive therapy can be instituted. These diagnostic and therapeutic techniques have led to a reevaluation of this malignancy and its prognosis.     

Acoustic neurinoma presenting as intratumoral bleeding

The authors report a case of acoustic neurinoma presenting as intratumoral bleeding. This is the tenth reported occurrence. The literature is reviewed. All cases that have been reported have appeared with sudden onset of headache, vomiting, and decreased levels of consciousness. Aneurysm rupture, an arteriovenous malformation, or other vascular anomalies are suspected first. Preexisting unilateral hearing impairment is a valuable clue to differential diagnosis. Contrast-enhanced computed tomographic scans and cerebral angiograms are important tools for correct diagnosis. The tumor size (greater than 2 cm) and the thin, dilated vessels within the tumor are considered as pathogenetic factors for bleeding. When neurological status is not stable, placement of a ventriculoperitoneal shunt followed by urgent extirpation of the tumor is indicated.     

Hepatic angiomyolipoma developing during the follow-up of ulcerative colitis: Report of a case and review of the literature

Hepatic angiomyolipoma is a rare tumor composed of spindle-shaped and epithelioid smooth muscle cells, adipose tissue, and proliferating blood vessels. We report the first documented case of this tumor developing in a patient with ulcerative colitis. A solitary tumor (7.5×7.5×7cm) was detected in the left lateral segment of the liver and a left hepatic lobectomy was performed. The diagnosis of angiomyolipoma was confirmed by a pathological examination. We also review the literature on previously reported cases of hepatic angiomyolipoma.     

肾嗜酸细胞腺瘤的诊断(附九例报告)

目的提高肾嗜酸细胞腺瘤的临床诊断及鉴别诊断水平。方法回顾９例肾嗜酸细胞腺瘤患者的临床及ＣＴ检查资料,对肿瘤标本行光镜和电镜观察,应用免疫组化ＬＳＡＢ法检测Ｃｙｔｏｋｅｒａｔｉｎ８（相对低分子质量角蛋白）和Ｖｉｍｅｎｔｉｎ（波型蛋白）,并与肾细胞癌相鉴别。结果ＣＴ增强扫描后肿瘤密度均匀一致,瘤体中央可见星状低密度区是该瘤的主要特征。病理组织学：肉眼观察肿瘤质均、无坏死、呈红棕色,部分肿瘤有中心瘢痕;光镜下胞浆强嗜酸性,粗颗粒,巢状或实片状排列,无坏死,无核分裂像或核分裂像罕见;Ｃｙｔｏｋｅｒａｔｉｎ８阳性,Ｖｉｍｅｎｔｉｎ阴性;电镜下有多量粗大线粒体。结论肾嗜酸细胞腺瘤是一种肾脏良性肿瘤,其ＣＴ影像特征有助于术前诊断。根据其组织学改变、免疫组化及电镜特点,可与胞浆嗜酸性肾癌鉴别。     

Lymphoepithelioma-Like Carcinoma of the Urinary Bladder: A Case Report and Discussion of Differential Diagnosis

Lymphoepithelioma-like carcinoma (LELC) of the urinary bladder is very rare. It is mandatory to make differential diagnosis among lymphoma, chronic cystitis and LELC because of different therapeutic approach. A bladder tumor was found in a 90-year-old patient suffering from hematuria. After transurethral resection, undifferentiated tumor with prominent lymphoid infiltration was seen on light microscopy. Immunohistochemical examination demonstrated positive staining of tumor cells with cytokeratin (CK), epithelial membrane antigen and CK-20. We presented the case because of its rarity and related literature was reviewed.     

Diaphragma sellae metastasis from colon carcinoma mimicking a meningioma. A case report.

We describe a rare case of metastatic intra-suprasellar adenocarcinoma from colonic cancer mimicking a meningioma of the "diaphragma sellae". Autopsy studies indicate breast and lung carcinoma to be the most frequent primary tumor metastasizing this site, particularly in patients with systemic spread. While diabetes insipidus is reported to be one of the commonest symptoms in these cases, the only clinical manifestation of the tumor in our patient was a bitemporal hemianopia, while the primary tumor remained asymptomatic. In the available literature are reported only two pituitary metastasis from operated colon carcinoma. In both cases the diagnosis of the colon cancer preceded the pituitary operation. The clinico-pathological and neuroradiological aspects of this unusual lesion are analyzed in the light of the relevant literature on the topic focusing on recent MRI acquisitions.     

Glomus tumor in the quadriceps ligament: a case report

We report a very rare localization of glomus tumor: the quadriceps ligament. The clinical diagnosis in this 19-year-old male patient was difficult. The final diagnosis was established at pathology examination of the surgical resection specimen. Resection provided cure. A review of the literature confirms that the quadriceps is a very rare localization of glomus tumor, no other cases have been reported previously.     

Primary cerebral neuroblastoma in an adult man

Survey of the literature reveals 10 cases of cerebral neuroblastoma in adults. An additional case, confirmed by electron microscopy, is reported here. The patient had a voluminous supratentorial calcified intraventricular tumor with clinical signs dating back more than two years. Despite the size and cellular immaturity of the lesion, surgical removal of the tumor was apparently satisfactory on macroscopic grounds. Treatment also included postoperative radiotherapy of the brain and spinal cord. The present case is discussed in light of the scarce data from the literature.     

Intraventricular neurocytoma, a recently recognized pathological entity: report of two cases and review of the literature.

Neurocytoma has only recently been recognized as a distinct pathological entity. Previously a rare tumor, it is now being recognized with increasing frequency. It typically presents in an intraventricular location in young adults. Many neurocytomas were originally diagnosed by light microscopy as oligodendrogliomas. More recently they have been shown to have ultrastructural and immunohistochemical features of neuronal differentiation. This paper presents two cases of intraventricular neurocytomas and reviews the recent literature.     

Primary leiomyosarcoma of the posterior mediastinum — A case report

Primary leiomyosarcoma (LMS) is an extremely rare tumour, which usually develops in the oesophagus or great vessels. Very few cases have been reported of LMS developing from small vessels of the soft tissues of the posterior mediastinum. We report a 43-year-old woman who presented with a large posterior mediastinal tumour. The tumour was surgically removed via right thoracotomy and the diagnosis of leiomyosarcoma was established. At operation no continuity was found between the tumour and neighbouring structures. This rare and interesting histopathology is discussed and the literature reviewed.     

Fibrosarcoma of the nose and the paranasal sinuses

We report a case of fibrosarcoma of the nose and paranasal sinuses and give a brief review of the literature. Fibrosarcoma of the nose and paranasal sinuses is uncommon, and few cases have been reported to date. Previously these tumors may have been overdiagnosed secondary to inadequate diagnostic procedures. Because histologic diagnosis is difficult, these tumors have been confused with other lesions of the head and neck. Thus, the improvement in diagnostic procedures has significantly reduced the reported incidence of fibrosarcoma. Because histologic diagnosis is difficult, this tumor has often been confused with other lesions of the head and neck. To ensure proper handling of the tissue, the pathologist should be informed if fibrosarcoma is suspected. It may be necessary to use electron microscopy or staining techniques such as immunoperoxidase stains to distinguish fibrosarcoma from other lesions. Unfortunately, the early signs and symptoms of the tumor are vague and sometimes misleading. Thus, at the patient's initial visit, it is important that the physician consider the possibility of fibrosarcoma.     

Laparoscopic resection of a large nonadrenal ganglioneuroma adhered to the aorta and inferior mesenteric artery: A case report and literature review

IntroductionGanglioneuromas are well-differentiated benign tumors that arise from sympathetic ganglion cells. In ganglioneuromas of the retroperitoneum, nonadrenal cases are resected by laparotomy due to the proximity to major vessels. There have been few reports of laparoscopic resection for retroperitoneal paraaortic ganglioneuromas. We experienced a case in which laparoscopic resection was required for a 90-mm ganglioneuroma adhered to the aorta and inferior mesenteric artery.Presentation of caseA 49-year-old female patient presented with epigastric pain. Computed tomography showed a 90 mm retroperitoneal tumor, partially located between the aorta and inferior mesenteric artery. A definitive diagnosis was not obtained, and laparoscopic excision of the retroperitoneal tumor was performed transabdominally. The patient recovered without postoperative complications and left the hospital on postoperative day 8. Postoperative pathological findings revealed a ganglioneuroma from the abdominal periaortic plexus.DiscussionWe searched the literature for nonadrenal ganglioneuromas resected laparoscopically using a transabdominal approach and summarized the tumor locations. The median age was 33 years, and the median tumor size was 50 mm. Regarding the surgical results, the median operative time was 170.5 min, median blood loss was 21.5 mL, and median postoperative stay was 7 days.ConclusionLaparoscopic resection of nonadrenal ganglioneuromas is feasible even when a tumor adheres to major blood vessels.     

The biological implications of bronchial tumors

Seventy-six consecutively resected primary pulmonary tumors were assessed first by routine light microscopy and subsequently by electron microscopy and immunohistochemical staining techniques to precisely identify features of differentiation. In 66% of the cases, this assessment provided information that modified or revised the histologic diagnosis provided by light microscopy alone. The following conclusions were reached: (1) The term "large cell undifferentiated carcinoma" has been applied to a heterogenous group of tumors, most of which have ultrastructural and immunohistochemical features of differentiation not identifiable by routine light microscopy. (2) Forty percent of the tumors previously called "large cell undifferentiated carcinoma" have predominantly neuroendocrine differentiation and appear to have a clinical course comparable to that of small cell neuroendocrine carcinoma. (3) The majority of pulmonary carcinomas (especially those previously called "poorly differentiated" or "undifferentiated") may simultaneously demonstrate more than one pattern of differentiation when studied by electron microscopy and immunohistochemistry. (4) The frequency of neuroendocrine neoplasms of the lung, as determined by these and previous studies, is considerably greater than suspected on the basis of light microscopic studies alone. These comprise a clinical and morphologic spectrum ranging from bronchial carcinoid to small cell carcinoma, all of which have immunohistochemically demonstrable hormone production, although paraneoplastic hormonal syndromes are manifested in only a small minority of cases.     

Renal cell carcinoma vs. renal oncocytoma. Report of a case with overlap features and review of the literature

Although the salient features of renal oncocytomas and renal cell carcinomas have been discussed in the recent literature, renal masses with features of both entities will present diagnostic difficulty, especially when the cells are diffusely eosinophilic on microscopic examination. A case of a firm, tan, rounded mass replacing the lower pole of the kidney is discussed. The final diagnosis of renal cell carcinoma, granular cell type, was made after multiple sections of the tumor were examined, and after electron microscopy was performed. A thorough search by light microscopy should be made for clear cell foci, necrosis, mitotic activity, and vascular or capsular invasion, features generally accepted as pathognomonic for renal cell carcinoma. Cellular and especially nuclear pleomorphism is typically focal or mild in renal oncocytomas. True oncocytic tumors will be packed with mitochondria on electron microscopy; however, granular renal cell carcinomas will contain mitochondria as well as other cellular organelles, lipid, and glycogen. Electron microscopy should be performed on tumors suspected of being oncocytomas because eosinophilia on hematoxylin and eosin stain, as demonstrated by this case, is not a predictable measure of mitochondria content. Immunoperoxidase staining for vimentin in oncocytomas has recently been shown to be negative, and may offer a method of ruling out oncocytoma in vimentin-positive tumors, pending further studies.     

Paraganglioma of the cauda equina. Case report with 33-month recurrence free follow-up and review of the literature

Paraganglioma of the cauda equina is an unusual tumor and do not have the secretory properties of the same tumors arising outside the nervous system. In none of the few cases reported in literature a preoperative diagnosis was possible, and the surgical findings raised questions in the differential diagnosis with ependymomas. A rare case of paraganglioma of the cauda equina studied both pre- and postoperatively by MRI, and treated with subtotal excision combined with radiotherapy is described. Results and recurrence rates of the cases reported in literature are reviewed. Though MRI imaging has proven to be more sensitive than other radiological procedures, we stress the difficulties of preoperative diagnosis of paragangliomas in this site. The correct diagnosis of the paraganglioma of the cauda equina still relies on immunochemistry and electron microscopy. Total excision is often very difficult owing the tendency of these neoplasms to infiltrate cauda's roots. A 33-month recurrence free follow-up of our patient confirms that successful treatment is achieved by subtotal resection combined with radiotherapy.     

Immunohistochemical demonstration of the endothelial nature of aortic intimal sarcoma

Primary sarcomas of the aorta are rare; fewer than 30 cases have been reported. Among these, the majority are intraluminal and apparently intimal in origin. Extensive histochemical and electron-microscopic evaluation of these tumors has not previously been performed. We present a case of aortic intimal sarcoma in a 70-year-old man whose resected aorta showed multifocal, intimal tumor that appeared on light microscopy to be undifferentiated sarcoma. Electron microscopy was not helpful; however, immunohistochemical studies confirmed the endothelial nature of this neoplasm. The multifocal pattern of the tumor and the presence of intervening, atypical, proliferative endothelial cells suggests that endothelial dysplasia may have been a precursor lesion.