1/7. Hepatic metastases from the spindle cell variant of medullary thyroid carcinoma: report of a case with diagnosis by fine needle aspiration biopsy.BACKGROUND: The liver is a common site of neuroendocrine tumors (NTs) metastatic from primaries in the gastrointestinal tract, pancreas, biliary system and lungs. Medullary thyroid carcinoma (MTC) is also a potential source of metastases of NTs. Their metastases to the liver are frequent and can appear several years after the primitive tumor. Although a wide variety of cytomorphologic features are normally exhibited by MTC in smears, a spindle-shaped cell pattern can predominate, complicating the correct interpretation of a metastasis. CASE: A 63-year-old man presented with multiple liver nodules two years after a total thyroidectomy for MTC. Fine needle aspiration biopsy smears of the liver revealed neoplastic cells occurring in loose groupings or lying singly, most of them with a spindle shape and elongated nucleus with the characteristic "salt and pepper" chromatin pattern of a neuroendocrine tumor. Cytoplasmic dendritic processes and intranuclear inclusions were frequently seen. The cytomorphologic features of the tumor were essentially the same as those of the primary MTC. Immunoreactivity for calcitonin confirmed the diagnosis. CONCLUSION: In fine needle aspiration biopsy of liver masses, knowledge of the spindle pattern of the NT is important in order to achieve a correct diagnosis when metastases are the first manifestation of an occult primary tumor. Among neuroendocrine tumors, MTC must be included in the differential diagnosis.- - - - - - - - - - ranking = 1keywords = nucleus (Clic here for more details about this article) |
2/7. brain involvement in multicentric Epstein-Barr virus-associated smooth muscle tumours in a child after kidney transplantation.Epstein-Barr virus (EBV)-associated smooth muscle tumours (SMT) have been reported in young patients with induced immunosuppression associated with organ transplantation, acquired immunodeficiency syndrome or congenital immunodeficiencies. EBV-associated SMT are frequently multicentric or multifocal and often occur in unusual locations. We are reporting a case of EBV-associated multicentric SMT that occurred after kidney transplantation in a 2-year-old boy with a history of oligomeganephrony. Headaches and left VIth cranial nerve paralysis led to the discovery of a brain tumour 3 years after transplantation. There were multiple pulmonary, hepatic and splenic nodules and enlarged mesenteric lymph nodes. Histological examination revealed multicentric SMT of uncertain malignant potential. Further investigations using in situ hybridisation demonstrated EBV early RNAs in the nucleus of most tumour cells. The immunosuppressive therapy was reduced, and the child was treated with chemotherapy, but died 2 months later, due to neurological complications.- - - - - - - - - - ranking = 1keywords = nucleus (Clic here for more details about this article) |
3/7. Lymphadenopathic form of alveolar rhabdomyosarcoma: A case report.We report the case of a special form of rhabdomyosarcoma called "lymphadenopathic" which was reported only two times in the literature. This lymphadenopathic alveolar RMS shows lymph nodes as clinical manifestation mimicking lymphoma with an unknown primary neoplasm. In the case we report, clinical examination, and radiological studies revealed superficial and deep located lymph nodes in association with bilateral pleural effusion. Conventional histological examination showed lymph node infiltration by a metastatic tumour having alveolar pattern. Some of tumour cells were round with multilobed off-centred nucleus and eosinophilic cytoplasm containing fibril material with longitudinal and transverse striation indicating a muscle nature of the tumour proliferation. The immunohistochemical study showed intense and diffuse immunoreactivity of tumour cells for vimentin and a discreet immunostaining by desmin. These findings were compatible with the diagnosis of lymph node metastasis by alveolar rhabdomyosarcoma.- - - - - - - - - - ranking = 1keywords = nucleus (Clic here for more details about this article) |
4/7. Primary neuroectodermal tumour of the testis.A 51-year-old male presented with metastasis of a small cell carcinoma of unknown origin in a right inguinal lymph node. Clinical and laboratory studies failed to locate the primary tumour. After three years, a swelling appeared in the right testis, which was removed. Histological examination revealed a proliferation of small tumour cells forming irregular masses or nests that occupied most of the testicular parenchyma. At the periphery of the testicular parenchyma a few seminiferous tubules could be observed, showing a low and incomplete seminiferous epithelium and numerous tumour cells in the lumen. Most of the tumour cells showed a euchromatic nucleus with small nucleoli and scanty cytoplasm. Among these cells, larger binucleate or trinucleate cells as well as small cells with pyknotic nuclei were also observed. Mitoses were numerous. Electron microscopy revealed some tumour cells with 80 to 100 nm vesicles containing electron-dense granules. Some cells displayed dendrite-like prolongations with numerous intermediate filaments and electron-dense vesicles. This tumour is compatible with a primary neuroectodermal tumour of the testis.- - - - - - - - - - ranking = 1keywords = nucleus (Clic here for more details about this article) |
5/7. "Very well differentiated tubular adenocarcinoma" of the stomach: its endoscopic and histopathological characteristics.Between 1986 and 1991, 31 patients having tubular adenocarcinoma with low cellular and structural atypism ("very well differentiated tubular adenocarcinoma:" tub 0) underwent surgery at the National Cancer Center Hospital (NCCH). Histologically, the 31 lesions in the 31 patients were very similar to those observed in gastric adenoma (world health organization) with severe atypism. Their malignancy could be diagnosed only on the basis of cellular atypism, i.e., uneven distribution of chromatin in the nucleus accompanied by irregularity in the size or shape of the spindle-form nucleus, abnormal nuclear polarity and/or obvious nucleoli. Histologically, the border between the tub 0 and adenomatous areas ('front line' of carcinoma) could not be identified within the neoplastic lesion, which showed relatively regularly shaped tubuli (less structural atypism). Of the 31 cases, 30 were solitary early gastric cancer (EGC). Their clinicopathological features were compared with those of 34 cases of gastric adenoma, 237 cases of solitary well differentiated (tub 1) and 127 cases of moderately differentiated (tub 2) tubular adenocarcinoma which had been resected at the NCCH during the same period. Most (75%) of the 30 tub 0 EGCs were type IIc (depressed) macroscopically, despite their histological similarity to gastric adenoma which showed a high (90%) elevated appearance incidence. The incidence of small lesions, < 2 cm in diameter, was highest in gastric adenoma (82%), followed by tub 0 (64%), although the tub 0 lesions showed a wide range of sizes. Small lesions were less frequent in the tub 1 (43%) and tub 2 (33%) cases. The incidence of submucosal invasion was significantly lower in tub 0 cases (17%) than in tub 1 (39%) and tub 2 (46%) cases (P < 0.05). No lymph node metastasis was seen in tub 0 cases, but was seen in 6.4% and 9.4% of tub 1 and tub 2 cases, respectively. With regard to the endoscopic appearance of depressed mucosal cancer, the incidence of encroachment (moth-eaten appearance) on the tips of folds was significantly lower (10%) and the appearance of marginal elevation was significantly higher (79%) in tub 0 than in tub 1 (each P < 0.05) or tub 2 (each P < 0.01). The results suggest that 'tub 0' can be regarded as a less malignant but not benign tumor, and that its endoscopic characteristics provide valuable information which can be used to ensure that patients receive suitable treatment.- - - - - - - - - - ranking = 2keywords = nucleus (Clic here for more details about this article) |
6/7. Fine-needle aspiration of epithelioid sarcoma.The cytologic appearance of epithelioid sarcoma in fine-needle aspiration biopsy (FNAB) has not been extensively described. The authors report the cytologic findings in one case that metastasized to a lymph node. The cells are characterized by irregular nuclei, nuclear folds, macronucleoli, and a high nucleus-cytoplasm ratio. The cells vary in shape and occur singly and in clusters where intercellular spaces are uncommon. The findings allow the diagnosis of malignancy but are nonspecific. history, immunocytochemistry, and tissue cores are helpful in the differential diagnosis.- - - - - - - - - - ranking = 1keywords = nucleus (Clic here for more details about this article) |
7/7. Isolated inferior rectus palsy caused by a metastasis to the oculomotor nucleus.PURPOSE: To report a case of isolated inferior rectus palsy secondary to a metastasis to the oculomotor nucleus. methods: Case report. A 41-year-old woman with a history of breast cancer presented with acute onset of left hypotropia and exotropia. RESULTS: Forced generation testing confirmed weakness of the right inferior rectus muscle that was not reversed by intravenous edrophonium infusion. magnetic resonance imaging disclosed numerous metastatic lesions to the cerebral hemispheres and brainstem. One lesion in the right midbrain was adjacent to the cerebral aqueduct in the right oculomotor nucleus. CONCLUSION: Metastasis to the oculomotor nucleus is a rare cause of isolated inferior rectus palsy; however, this entity should be considered in the differential diagnosis of an isolated inferior rectus palsy because of the life-threatening consequences of a brainstem lesion.- - - - - - - - - - ranking = 7keywords = nucleus (Clic here for more details about this article) |