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1.
Background and Aim: Duodenal lymphangitis carcinomatosa has been sporadically described, but so far little attention has been paid to duodenal lymphangitis carcinomatosa. Methods: Four cases with duodenal lymphangitis carcinomatosa were endoscopically and histologically examined. Results: The four cases exhibited multiple polypoid lesions along the Kerckring's folds and/or were covered by characteristically granular, non‐ulcerated mucosa upon thickening. The granularity seems to been caused by dilated lymph vessels containing the carcinoma cells. The lesions were microscopically characterized by: (i) involvement of lymph vessels located in the upper portion of the lamina propria; (ii) no inflammatory changes; and (iii) no desmoplastic changes. Primary sites were thought to be the stomach in case 1, the pancreas in cases 2 and 4, and unknown in case 3. All patients died within 6 months after admission or endoscopic examination. Conclusions: As duodenal lymphangitis carcinomatosis shows characteristic endoscopic appearance, endoscopic diagnosis is not difficult. We should realize that the lesion represents extremely poor prognosis, and it should be distinguished from ordinary metastatic duodenal carcinoma.  相似文献   
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Background: Colonic pseudolipomatosis is rare and the pathogenesis is controversial. The purpose of the present paper was to clarify endoscopic and histological characteristics of colonic pseudolipomatosis and to discuss the etiology. Methods: A total of 15 lesions from 14 patients was reviewed. They were able to be histologically classified into two groups on the basis of variety in size of the vacuoles: Group A, the ratio of largest vacuole to smallest vacuole in size is less than three, Group B, the ratio is more than four. Results: Four of 15 lesions were group A, and were endoscopically polypoid or flat lesions covered with normal‐looking mucosa. They were microscopically characterized by (i) predominant location in the upper portion of the lamina propria; (ii) no submucosal involvement; (iii) less variation in vacuolar size; and (iv) no association with lymph follicles. The vacuoles of group A contained proteinaceous materials in two of four lesions. Group B (11 lesions) had small elevated mucosa with normal‐looking surface or non‐elevated reddish mucosa. Microscopically, the lesions were mainly located in the lower portion of the lamina propria, occasionally also in the submucosa, had variable‐sized vacuoles, and were related to lymph follicles. Conclusion: It is suggested that the vacuoles in group A contain fluid, and may indicate an abnormal stagnation of interstitial fluid. Microscopic appearance of group B is essentially similar to that of pneumatosis coli. It is thought that group B probably results from penetration of gas from the crypts into the mucosa during colonoscopy. It is unclear why group B had a preference for ileocecal valve and an association with lymph follicles.  相似文献   
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BACKGROUND: We examined the incidence and natural history of simple renal cysts found by ultrasonography (US) in patients referred for asymptomatic microscopic hematuria. METHODS: Among the 906 patients aged 18-78 years, 743 patients who had undergone US were included in the present study. The natural history of simple renal cysts was investigated in 55 patients who underwent periodical US examinations for more than 3 years. RESULTS: The incidence of simple renal cysts was 4.3% for ages 29 years or younger, 15.3% for ages 30-39, 21.8% for ages 40-49, 23.3% for ages 50-59 and 32.6% for ages 60 years or older; thus the incidence increased in older age groups (P = 0.0005 for men, P = 0.0020 for women). Men tended to have a higher incidence than women. The degree of hematuria did not influence the incidence of renal cysts (P = 0.9044). The annual growth rate of the mean maximum diameter was 4.2% during a 3-year follow-up period in 55 patients and 5.1% during a 6-year follow-up in 31 patients. CONCLUSION: Since the diameter of a renal cyst may increase by 5% annually, the diameter of the cyst may increase by 1.6 times in 10 years. The scheduling of follow-up examinations depends on the size at the time of disclosure, the effects on calyceal systems, or the suspicion of a concurrent malignant disease. However, the most simple renal cysts may be followed-up at an interval of more than 10 years, once a diagnosis has been established.  相似文献   
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We report an unusual case of chronic expanding hematoma in the psoas muscle. A 53-year-old man was admitted for evaluation of a mass shadow in the left lower lung field on chest X-rays. He had also been suffering from dull left back pain. A computed tomography scan showed a cystic lesion with a rim enhancement in the left retroperitoneal space. Mixed signal intensity in a mosaic pattern was seen on a T2-weighted magnetic resonance image. We could not rule out a suspicion of a neoplastic intratumoral hemorrhage. Due to increased pain and the definite diagnosis, surgery was performed. Histopathological examination confirmed the diagnosis of chronic expanding hematoma. The expansion process is thought to be due to the irritant effects of blood and its breakdown products, which cause repeated exudation and bleeding from capillaries in the granulation tissues.  相似文献   
8.
We report a rare case of pelvic malignant paraganglioma that was treated with surgery, combination chemotherapy and radiation. A 47-year-old man was diagnosed with pelvic malignant paraganglioma that had metastasised to the thoracic vertebrae. The pelvic mass, which was 6 cm in size, was on the posterior side of the bladder and had invaded the prostate, seminal vesicle and bladder neck. We resected the intrapelvic tumor and lymph nodes using cystoprostatectomy. Metastases to bilateral obturator lymph nodes and the right internal iliac lymph node were shown by pathology. Adjuvant therapies included six courses of the combination chemotherapy (cyclophosphamide, vincristine and dacarbazine), and 12 courses of VP-16 therapy. Radiation therapy was done for metastasis of the thoracic vertebrae. Local recurrence, progression of bone metastasis and new metastasis have not been detected since these treatments. The patient has been clinically stable during 20 months of follow-up. Chemotherapy of cyclophosphamide, vincristine and dacarbazine and VP-16 with radiation appears to be effective in treating advanced malignant paraganglioma.  相似文献   
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Background. The nail area is commonly affected by malignant melanoma. The prognosis of malignant melanoma of the nail is poor, becuase at the time of diagnosis most lesions are in the advanced stage. Correct diagnosis of early lesions could improve the prognosis. Methods. For 3 years, all patients with nail pigmentation at the dermatology clinic were screened for five specific criteria for the diagnosis of early lesions of malignant melanoma. Histologic examination was performed on 10 of 29 lesions. Results. Five of the 29 lesions were advanced malignant melanoma, easily diagnosed clinically. Two of the remaining 24 lesions fulfilled most of our clinical criteria of early malignant melanoma of the nail apparatus; that is, they appeared as melanonychia striata during adulthood, were wide in breadth measuring 9 and 11 mm, and showed variegated shades of brown. Periungual pigmented macule (Hutchinson's sign) was observed in one of the two cases. Total resection of the lesions was performed, followed by skin grafting. Conclusions. Histologically, an increased number of atypical melanocytes, mainly arranged as solitary units, were observed only in the epithelia of the nail matrix and of the nail-bed, confirming that these lesions were “ungual” malignant melanoma in situ. Such an early lesion of malignant melanoma of the nail apparatus can be completely cured with conservative excision, and the phalanx of the affected digit can be preserved.  相似文献   
10.
In a series of 2,013 gastric polyps in 1,201 patients, morphological and histopathological studies have been performed. Ninety-three hyperplastic polyps in 56 patients have been followed-up endoscopically and histopathologically for five to 12 years. The incidence of detection of gastric polyps has increased: 1.4% in 1967 to 8.7% in 1979 year by year. Thirty patients (54%) among the 56 showed changes in number, size or shape of polyps during follow-up. Twenty patients (37%) revealed numerical changes (increase in 16 patients, reversion in three patients and vanishing in two patients).
Twenty-eight polyps (30%) showed morphological changes, six of them showed continuous enlargement, 18 lesions repeated enlargement, stationary or reduction stages, three lesions were reversed and two polyps disappeared.
Histopathologically, three lesions showed transformation from the hyperplastic type to adenoma while demonstrating morphological enlargement. Two of these showed increase in cellular atypia, from the hyperplastic type through adenoma with severe atypia and finally to carcinoma in the polypectomy specimens. From this study, it was concluded that although hyperplastic polyps show changes in size, shape or number with passage of time, malignant changes occur in only a few cases.  相似文献   
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