Monomorphic agranular natural killer cell lymphoma/leukemia with no Epstein-Barr virus association.

The conceptual view of natural killer (NK) cell malignancies has recently undergone a significant evolution. The majority of such diseases are associated with Epstein-Barr virus (EBV), while only a limited number of EBV-negative cases has been reported. We report an unusual case of NK cell lymphoma/leukemia showing a monomorphic histology, absence of intracytoplasmic azurophilic granules, and no EBV association. The patient was a 57-year-old woman who died 26 months after the diagnosis. Autopsy revealed tumor infiltration in the liver, spleen, lymph node, blood, and bone marrow. There was no involvement of the skin or nasal cavity throughout the clinical course. The tumor showed the monotonous proliferation of medium-sized cells without intracytoplasmic azurophilic granules. Phenotypic analysis showed CD2+, CD3/Leu4-, cytoplasmic CD3epsilon+, CD4-, CD5-, CD7+, CD8-, CD16-, CD38+, CD56+, CD57-, TdT-, granzyme B-, and TIA1+ phenotype. There were no detectable rearrangements of T cell receptor genes or immunoglobulin heavy chain genes. Furthermore, there were no EBV-encoded small RNAs. These findings provide information to improve the understanding of poorly defined entities, i.e. aggressive NK cell lymphoma/leukemia and blastic NK cell lymphoma/leukemia.

201Tl SPET in the differential diagnosis of brain tumours.

The aims of this study were to assess the utility of 201Tl single photon emission tomography (SPET) in the differential diagnosis of brain tumours and to elucidate the relationship between 201Tl tumour uptake and degree of contrast-enhancement on magnetic resonance imaging (MRI). Early (15 min) and delayed (3 h) 201Tl SPET imaging and T1-weighted MRI were performed before and after Gd-DTPA enhancement in 101 (41 malignant and 60 benign) untreated brain tumours. The 201Tl uptake ratio (tumour-to-normal brain count ratio) for both the early and delayed SPET studies and the retention index (the ratio of delayed to early 201Tl uptake) were calculated. Malignant tumours were separated from benign tumours with 87% accuracy based on the assumption that tumours with a 201Tl retention index < 0.7 or no abnormal uptake are benign. Meningiomas and pituitary adenomas were differentiated from other benign tumours by their characteristic pattern on SPET. The degree of contrast-enhancement of the tumour on MRI was concordant with the early 201Tl uptake ratio for most histological types. However, schwannomas and cavernous haemangiomas showed a low 201Tl uptake ratio in spite of a high degree of contrast-enhancement on MRI. In conclusion, 201Tl SPET provides additional information that helps in the differential diagnosis of brain tumours.

Cardiac tamponade originating from primary gastric signet ring cell carcinoma.

A 45-year-old man with dry cough and dyspnea was referred by a medical practitioner for evaluation of heart failure on February 10, 1996. Chest X-ray revealed increased cardiothoracic ratio, and ultrasonographic echocardiography disclosed massive pericardial effusion with right ventricular collapse. Cardiac tamponade was diagnosed and pericardiocentesis was performed. Ten days after admission, the pleural effusion had become more pronounced, and thoracocentesis was performed. Carcinoembryonic antigen level was elevated in both the pericardial and pleural effusion, and cytology implicated adenocarcinoma, which suggested malignant effusion. Endoscopic study disclosed gastric cancer in the posterior wall of the upper body, and the histopathological diagnosis was signet-ring cell carcinoma. The patient died of respiratory failure on May 2, 1996, and autopsy was performed. The final diagnosis was gastric cancer with pulmonary lymphangitis, pericarditis, and pleuritis carcinomatosa, accompanied by enlargement of mediastinal and paraaortic lymph nodes. Interestingly, the primary signet-ring cell carcinoma of the stomach was situated mostly in the mucosa. Deep in the submucosal region, there was prominent invasion of the intralymphatic vessels, without direct destruction of the mucosa muscularis.

Primary hepatic lymphoma in a patient with chronic hepatitis B.

Primary hepatic lymphoma is a rare disorder and the clinical behavior remains unknown. We report a patient with primary hepatic lymphoma who had chronic hepatitis B. She was asymptomatic; however, a solitary tumor in the left lobe was incidentally detected. After left hepatic lobectomy was performed, a diagnosis of non-Hodgkin's lymphoma was made. No tumor was found except in the liver. Immunohistochemical stains for hepatitis B surface and core antigens were positive in hepatocytes; however, both were negative in the tumor tissue. The patient received no chemotherapy and the tumor relapsed. After chemotherapy, the tumor disappeared. However, exacerbation of hepatitis occurred after the fourth chemotherapy. The patient was followed up without chemotherapy, and she remains in apparent remission. Chemotherapy is effective against primary hepatic lymphoma and, if possible, patients with this disorder should be treated with chemotherapy postoperatively.

Thyroid nodules: evaluation with US-guided core biopsy with an automated biopsy gun.

To evaluate the efficacy of ultrasound (US)-guided automated core biopsy of thyroid nodules, 74 biopsies were performed in 61 consecutive patients with an 18-gauge short-throw (1.1-cm excursion) biopsy gun. Results were correlated with diagnoses made at surgery (n = 38) or at sonographic follow-up of at least 6 months (n = 36). Sensitivity, specificity, and accuracy of diagnoses made with automated core biopsy were 84%, 95%, and 91%, respectively. US-guided biopsy with an automated biopsy gun allowed accurate assessment of thyroid nodules.

[US-guided core biopsy of the breast with an automated biopsy gun: comparison with an aspiration core needle device].

To evaluate the efficacy of an automated Tru-cut type of biopsy gun in US-guided breast biopsy, we performed 162 breast biopsies in 148 patients using an 18 gauge short-throw (1.1cm excursion) Tru-cut-type biopsy gun (Ace-cut needle). The results of the series were compared with another series of aspiration core biopsies, which were performed on 113 breast lesions in 112 patients using an 18 gauge Sure-cut needle. The results of the two series were correlated with the diagnoses made at surgery or clinical follow-up. Sensitivity, specificity, and accuracy for the automated biopsy gun were 89.2%, 94.9%, and 92.7%, and for the Sure-cut needle, 75.0%, 78.6%, and 77.5%, respectively (p < 0.01 for specificity and accuracy, by chi 2 test). There were no serious complications. The diagnostic surgical biopsy to operated cancer ratios in 1991 (without core biopsy), 1993 (with aspiration core biopsy), and 1995 (with automated core biopsy) were 2.9 (46/10), 2.0 (30/17), and 0.5 (12/24), respectively. We concluded that US-guided breast biopsy with an automated biopsy gun is a safe and highly accurate method, and could replace the diagnostic surgical biopsy.

Tsukuba high- and low-emotional strains of rats (Rattus norvegicus): an overview.

This report compiles the results of a series of studies on the Tsukuba High- and Low-Emotional strains (THE and TLE) of rats (Rattus norvegicus) established at the University of Tsukuba, Japan. The THE and TLE strains have been selected, respectively, for low and high activity in a runway test. During the course of selection, defecation has increased in the THE strain and decreased in the TLE strain. These strain differences were not affected by maternal influences, early experience, or psychotropic drugs. THE rats were consistently inactive in all novel situations examined, while TLEs were very active. The level of spontaneous activity, however, was similar between the two strains. It was remarkable that THE rats showed more burrowing activity than TLE animals, whereas the latter displayed more aggression than the former. Differences in learning ability, concentration of neural transmitters, and social behavior were examined.

Studies on the autonomic nervous function in Tsukuba emotional rats--with special reference to their cardiac function.

Autonomic nervous function in Tsukuba high (THE) and low (TLE) emotional rats as well as Wistar rats (control) was studied by means of electrocardiographical examination in addition to the runway test. In the runway test, locomotive activity differed significantly among the three strains, the greatest activity in TLE and the smallest in THE. Electrocardiogram (ECG) and locomotive activity were successively recorded for 24 hr using a small size of telemeter system. Though the locomotive activity showed a clear nocturnal rhythm, no significant difference was observed among the three strains. The mean value of R-R intervals in THE tended to be smaller than those in other two strains; showing a significant difference between THE and TLE. The mean value of standard deviation (SD) of R-R intervals in TLE tended to be larger than those in other two strains; showing a significant difference between TLE and Wistar in the light and dark periods, and also between TLE and THE in the light period. As regards coefficients of variation of R-R intervals (CV), there was no significant difference among the three strains. Autonomic nervous tone in THE and TLE was evaluated by means of autonomic blockades using atropine and/or propranolol. The sympathetic nervous tone represented 21.6% in THE and 16.8% in TLE, while the parasympathetic nervous tone -9.0% and -12.3% in THE and TLE, respectively. There was a significant difference in the net autonomic nervous tone between THE (10.7%) and TLE (-6.6%).(ABSTRACT TRUNCATED AT 250 WORDS)

Mucin-producing poorly differentiated adenocarcinoma of the thyroid. A case report.

A rare case of mucin-producing poorly differentiated adenocarcinoma of the thyroid is reported in a 58-year-old man. Light microscopically, the tumor composed of columnar cells, cuboidal cells and spindle cells and these tumor cells showed a various growth pattern; glandular growth with columnar cells, microfollicular growth with cuboidal cells and solid growth with spindle cells. Mucin histochemistry showed scattered foci of mucin production. Immunohistochemistry showed a focal positive staining for thyroglobulin and carcinoembryonic antigen, but a negative staining for calcitonin throughout the tumor. The patient had cervical and axillary lymph node recurrences after the radical operation. The histologic finding of this tumor is peculiar; we report this case briefly.

[A case of metastatic hepatocellular carcinoma of the superior mediastinum].

A 58-year-old man, who had undergone right hepatic lobectomy for hepatocellular carcinoma 6 years before, complained of hoarseness because of right recurrent laryngeal nerve paralysis. Chest X-ray film showed a large mass shadow in the superior mediastinum. On chest CT scan the mass was considered to be swollen paratracheal lymph nodes. Percutaneous aspiration biopsy of the mass demonstrated malignant epithelial cells. It was suspected that the hepatocellular carcinoma solitarily metastasized to the paratracheal lymph nodes. Right thoracotomy was done and the mediastinal tumor was resected. Microscopic examination of the resected specimen proved that the tumor was a metastatic hepatocellular carcinoma not of the lymph nodes, but of the fibroadipose tissue of the mediastinum. Metastasis of hepatocellular carcinoma to the mediastinal fibroadipose tissue is uncommon. To our knowledge, our case is the first report of hepatocellular carcinoma which shows such a metastasis.

[A case of subclavian paraganglioma in the superior mediastinum extending to the neck].

A 52-year-old female was admitted to our hospital with left anterior chest pain. On physical examination, an elastic hard mass sized in 3.0 x 2.5 cm was palpable at the left suprasternal area. Chest X-ray film showed a large mass shadow in the cervico-thoracic region, and CT films revealed a well-defined mass in the superior mediastinum which was heterogeneously enhanced by contrast medium. Operation was performed under the preoperative diagnosis of thymic tumor extending upwards. At operation, the tumor was located between the trachea and the left subclavian artery in the superior mediastinum displacing these structures and extending to the neck. Resected specimen which was 5.5 x 3.5 x 3.0 cm in size and 42 gm in weight was well encapsulated and highly vascularized. On microscopic findings, the tumor was finally diagnosed as paraganglioma. According to the classification of Glenner and Grimley, it was thought that the tumor originated from subclavian paraganglion in the superior mediastinum. Subclavian paraganglioma had rarely been reported in the literatures. As subclavian paraganglioma, our patient was the first reported case in Japan.

[A case of dumb-bell-like neurilemmoma of the posterior mediastinum].

A 56 year-old female was pointed out an abnormal shadow on chest X-ray film for the lung cancer screening study. Chest X-ray film showed a round mass shadow at the right superior mediastinum. Chest CT scan revealed the mass was in the paravertebral area abutting on the 2nd thoracic vertebral body and had extended into the intervertebral foramen. Preoperative diagnosis was a dumb-bell-like neurogenic tumor. Operation was carried out by posterior approach in the prone position. At first thoracotomy was done by removing the paravertebral portion of the 2nd and 3rd ribs, and then hemilaminectomy was added. Both the intrathoracic and intraforminal portions of the tumor were completely exposed, and excised. Pathological examination demonstrated the tumor was a typical neurilemmoma originating from the 2nd intercostal nerve. When a neurogenic tumor of the posterior mediastinum has an intraspinal extension, a posterior approach by a simultaneous thoracotomy and laminectomy will be useful to remove the tumor at one sitting.

[The sequential structures of social behavior and their developmental changes in rats bidirectionally selected for emotionality].

Eighteen colonies of Tsukuba High Emotional (THE) and 17 colonies of Low Emotional (TLE), each one composing of one female and two male rats, were reared for about two months. During this period, intruder tests and intra-colony observations were conducted once a week. Social behavior of colony residents was coded sequentially with 17 items in a microcomputer. Transitions in chi 2 tests were visualized in a tree structure. The sequential structures of social behavior were compared between two strains of rat in the course of social dominance organization. Although TLE males were more aggressive than THE males, dominant males of both strains had almost the same transition structure constructed of four common sequentially bound item-groups; alpha group (bite, lunge, aggressive groom), beta group (on-top related items), gamma group (chase, lateral display, boxing, on-back), and delta group (flight, retreat, defensive upright). beta items were found to be sequentially located after bite in alpha group. delta group was disappeared with dominance organization. But there were some differences in inter- and intra-group structures between THE and TLE.