Abstract
As gastric sarcoma responds well to chemotherapy or radiotherapy and its postoperative prognosis is relatively fair, its correct preoperative diagnosis is imperative. Endoscopic diagnosis of gastric sarcoma, however, still remains extremely difficult. Solid foundation for endoscopic diagnosis is provided by a close study of gross appearance. Since the cases of gastric sarcoma an institute can experience are limited, it would be of importance to describe precisely the gross appearance of resected specimens of gastric sarcoma, to which we had an access.Materials and Methods Gastric sarcoma in the surgical materials resected at the University of Tokyo Hospital during the period from January 1960 to June 197 were studied with reference to the incidence, location within the stomach and gross findings of the mucosal aspect, particularly of ulcerative lesions in reticulum cell sarcoma, with the aid of their gross photographs and histological specimens.Results and Discussion Twenty-seven cases of gastric sarcoma including 20 cases of malignant lymphoma and 7 cases of leiomyo-sarcoma were found in 3327 stomachs resected during the above-mentioned period, comprising 0.8 % of all the gastrectomy cases. The incidence of sarcoma in all the gastric malignancies was 1.3% during the last six and a half years. The ratio of malignant lymphoma to leiomyosarcoma was 3; 1. Those results coincide with the hitherto published reports. Malignant lymphoma encountered was only reticulum cell sarcoma; lymphosarcoma and Hodgkin's disease were not included. The predominance of reticulum cell sarcoma consistent with the other Japanese reports is in contrast with that of lymphosarcoma among the Caucasians, which is said to represent a racial difference.1. Reticulum cell sarcoma The age and sex distribution showed the mean age of 45.5 years, with the range of the 3rd to 7th decade, without sex preference. Location of the lesions showed that 16 of 19 cases involved the pars angularis or distal to it, which is in accordance with many reports (Nakamura, Palmer, Thorbjornarson et al, Joseph & Lattes) . Size of 29 lesions in 19 cases ranged from 0.7cm to 15 cm in greater diametre with the mean ±S.D, being 5.9±4.8cm Gross classification was made according to the degree of protrusion or depression of the tumour from the mucosal surface of the uninvolved area into the following three : ulcerative, diffuse infiltration and tumour formation types. Of 19 cases, 14 were classified as ulcerative type, of which 5 had multiple ulcerations ;1 case was of diffuse infiltration type featured by diffuse mural thickening and the other 4 cases were of tumour formation type. It should be noted that the ulcerative lesions in the cases with multiple ulcerations were not necessarily of sarcomatous nature ; in a case with 5 ulcerations, status post gastric irradiation, 4 lesions were free of sarcomatous involvement. Three of 4 cases of tumour formation type had multilobated fungating tumours ; each lobe or nodule was rounded, partitioned by deep sulci ; the overlying mucosa was generally smooth with lustre, partially with haemorrhage and adherance of necrotic materials. Such a shape has never been encountered in the other diseases, except probably in some of Palmer's collected cases of other sarcomas. The other cases of tumour formation type had a single Borrmann 1 type mass with a wide, shallow ulceration at the top. No case with the shape of the so-called submucosal tumour was seen in this series, though rarely reported in the literature and included in our unresected, autopsy cases. The depth of involvement was intramucosal in 1 case, submucosal in 3, both of which gave rise to the apperance mimicking early gastric carcinoma the involvement down to the muscularis propria was seen in 5 cases, subserosal in 5, serosal in 4. The primary focus of malignant lymphoma has been believed to be the lymphoid tissue in the submucosa, but Snoddy also reported a case o
