Symptomatic gastric amyloidosis in patients with primary systemic amyloidosis.

We reviewed the clinical records of 769 patients with primary systemic amyloidosis who had been examined at Mayo Clinic Jacksonville (Jacksonville, Florida) or Mayo Clinic Rochester (Rochester, Minnesota) during a 12-year period (1978 through 1989). Of these 769 patients, 59 (8%) had biopsy-established gastrointestinal amyloidosis, and 8 (1%) had symptomatic gastric amyloidosis. All eight patients with symptomatic gastric amyloidosis had hematemesis or prolonged nausea and vomiting in association with weight loss. Additional findings were gastroparesis (in three patients), gastric tumor (in one), and gastric outlet obstruction (in one). Macroglossia was present in two patients, and multiple myeloma was diagnosed in three. Six of the eight patients had coexisting small bowel amyloidosis and weight losses of 6.5 to 22.5 kg. Congo red staining identified gastric amyloid in the media of blood vessels in all cases. All cases stained selectively for lambda (seven cases) or kappa (one) light chain. All eight patients died; the median duration of survival after diagnosis was 13.8 months (range, 0.5 to 39.5). Death was due to cardiac failure (three patients), renal failure (two), chronic gastrointestinal obstruction and severe cachexia (two), or hepatic failure (one). Chemotherapy was given to seven patients but was only partially effective for ameliorating symptoms in one.