[Histamine levels in the blood in patients with malignant tumors].

The concentration of histamine in blood was determined in 22 patients with solid malignant tumors, 16 hospitalized non-cancer patients and 9 healthy subjects. Patients with cancer (mainly carcinomas of the breast and gastrointestinal tract) were divided into two groups: patients with resected primary tumor without known metastases (group I) and patients with present primary tumor with or without metastases (group II). In comparison with the healthy subjects (histamine concentration 69.0 +/- 6.03 ng.ml-1), cancer patients in both groups had significantly decreased levels of histamine in blood. Also, the concentration of histamine in patients with present tumor (group II; 40.1 +/- 3.48 ng.ml-1) vas significantly lower than in patients with resected primary tumor (49.9 +/- 3.14 ng.ml-1). Furthermore, hospitalized non-cancer patients had lower, but not statistically significant, concentration of histamine (59.7 +/- 6.13 ng.ml-1) than healthy subjects. These findings, together with similar data of other authors, suggest that decreased level of histamine in blood might be a good nonspecific marker for onset and progression of solid malignant tumors.