Comparison between number of basophils, blood histamine, and histamine release in cancer and noncancer patients.

In cancer patients with primary tumor with or without metastasis or metastasis alone, by comparison with healthy subjects and noncancer patients, the decrease in blood histamine levels is due to a decrease in total basophil number. These basophils have a normal content of histamine (1 to 2 pg per basophil) and are able to release histamine. The percentage of anti IgE-induced histamine release is not significantly different than in noncancer patients. The scarcity of basophils in cancer patients is not due to a leukopenia. Blood histamine levels and total basophil number are normal in patients after successful excision of their primary tumor without metastasis.