MUCOSAL LYMPHANGIECTASIA IN GASTRIC ADENOCARCINOMA

Objective.-To describe the occurrence and significance of mucosal lymp hangiectasia in gastric adenocarcinoma. Design.-One hundred consecutiv e gastrectomies for adenocarcinoma were reviewed, using 25 consecutive gastroscopically biopsied gastrectomy specimens with peptic ulcers as negative controls. Setting,-The specimens were collected over a perio d of 25 months in two general hospitals and processed according to a s tandard protocol. Patients.-Chinese living in Hong Kong. Results.-Twen ty cases of adenocarcinoma were found to show mucosal lymphangiectasia , which was arbitrarily defined as the presence of ectatic lymphatic c hannels in the lamina propria having maximum dimensions greater than t hat of a foveolar gland. The ectatic lymphatics were lined by simple e ndothelium, devoid of fibromuscular wall, and they either were optical ly empty or contained scant mononuclear leukocytes. None of the patien ts had preoperative evidence of malabsorption syndrome or protein-losi ng enteropathy. Lymphangiectasia was most readily seen in the superfic ial lamina propria near the main tumor. In 10 cases (50%), lymphangiec tasia extended to the nonneoplastic part of the gastric mucosa, at a d istance of at least 2 cm away from the main tumor. Tumor emboli were s een in the ectatic lymphatics in 11 cases (55%). In two cases (10%), t he distal line of resection was involved by intramucosal lymphatic spr ead. The tumor permeating the lymphatics did not evoke any inflammator y or desmoplastic reaction in the perilymphatic lamina propria, simila r to the phenomenon of so-called lymphangitis carcinomatosa. In eight cases (40%), there were foci beyond the main tumor where mucosal lymph angiectasia was present, but without tumor in its immediate vicinity. All (100%) of the 20 stomachs with mucosal lymphangiectasia had metast ases in regional lymph nodes, whereas only 59 of the 80 cases (73.75%) without lymphangiectasia were node-positive (P <.025). All node-negat ive cases did not show lymphangiectasia. Twenty-five consecutive gastr ectomies for peptic ulcer disease that had undergone preoperative muco sal biopsies showed no lymphangiectasia, suggesting that mucosal biops y was not the cause of mucosal lymphangiectasia. Conclusions.-(1) Gast ric mucosal lymphangiectasia is associated with carcinoma but not pept ic ulcer, (2) Mucosal lymphangiectasia in gastric carcinoma signifies lymph node metastases, and (3) Gastric carcinoma can spread along the mucosa via intramucosal lymphatics.