No abstract

Monoclonal antibodies directed against tumor-associated antigens of bladder carcinoma were used to identify tumor cells in bladder washout specimens of 40 patients with bladder carcinoma (group 1), 41 with no bladder disease or with urinary tract infections (group 2), 41 who received long-term mitomycin C instillation therapy after excision of the tumors (group 3) and 39 who received no prophylaxis after excision of the tumors (group 4). In all groups the same bladder washout specimen was used for standard urinary cytological and immunocytological tests. True positive results were obtained in 90 per cent of the patients in group 1 according to our immunocytological criteria and in 43 per cent according to standard cytology studies. No urine specimens in group 2 (controls) were immunocytologically positive, while 16 of 41 in group 3 and 17 of 39 in group 4 were positive immunocytologically but only 4 and 5, respectively, were positive according to standard cytology studies. Further followup of these patients will show whether cells positive for monoclonal antibody 486 P 3/12 will permit early detection of recurrent bladder cancer and whether one can identify patients who require prophylaxis after removal of the superficial bladder tumors.

Compared with total and free PSA hK2 testing improved the preoperative evaluation of patients who underwent radical retropubic prostatectomy due to the superior discrimination of organ from non-organ confined cancer.

Blood eosinophilia in tumor patients treated with interleukin-2 (IL-2) is well known and is regarded as evidence of toxicity or as a side-effect [Lotze et al. (1986) Arch Surg 121:1373-1379; West et al. (1987) N Engl J Med 316:898-905]. We recently described a new local IL-2 approach to therapy for advanced bladder carcinoma that allows, for the first time, high-dose continuous administration of natural interleukin-2 (nIL-2) at the tumor site without side-effects [Huland and Huland (1989) Cancer Res 49:5469-5474]. Tumor-associated eosinophilia of up to 65% (i.e. eosinophils constituting 65% of leukocytes) was seen in four of five patients after treatment, but never before treatment or in untreated controls. Activated eosinophils were attached to bladder tumor cells. Local activation was seen only after natural IL-2 treatment and was determined by cytological criteria and by staining with monoclonal antibody (mAb) EG1 directed against all eosinophil granule proteins and mAb EG2 directed against the active secretory granule proteins of the eosinophils. Bladder cancer cells in urinary sediment also stained with these two mAbs, revealing active degranulation of eosinophils on bladder tumor cells. The number of eosinophils in blood increased, however, without signs of activation. These data constitute strong evidence that activated eosinophils in vivo are involved in the IL-2-induced antitumor response.