Thomas Menzel

Expansion of Peripheral Blood Natural Killer Cells Correlates with Clinical Outcome in Cancer Patients Receiving Recombinant Subcutaneous lnterleukin-2 and Interferon-α-2

Natural killer (NK) cells are believed to contribute to the clinical efficacy of cancer immunotherapy using recombinant interleukin-2 (rIL-2) in humans. In previous trials of high-dose i.v. rIL-2, however, no correlation has been established between circulating NK cells and treatment response. Between January 1989 and October 1990, we treated a total of 47 outpatients with advanced tumors using low-dose s.c. rIL-2 and interferon-alpha-2 (rIFN-alpha). Therapy consisted of a 2-day rIL-2 pulse at 18 million IU/m2/day, followed by 6 weeks of rIL-2 (3.6 x 10(6)-4.8 x 10(6) IU/m2/day x 5 days/week) and rIFN-alpha (5 x 10(6)-6 x 10(6) U/m2 x 3/week). Before and after therapy, we phenotypically evaluated circulating lymphocytes and correlated them with clinical response. During 6-week therapy, peripheral blood lymphocytes bearing the CD56 (NK-cell-associated) surface antigen were increased significantly (p < or = 0.005) in treatment responders [complete response (CR) and partial response (PR), n = 10; 3.8-fold] and stable disease (SD) patients (n = 20; 2.1-fold), while patients with progressive disease (PD, n = 17) exhibited no significant expansion of circulating NK cells (p > 0.1). After one 6-week treatment cycle, CR/PR patients had significantly more peripheral NK cells, when compared with patients in SD (1.6-fold) and PD (1.9-fold) (p < 0.04). The overall number of circulating lymphocytes was also increased upon therapy (1.6-fold; p < or = 0.001), but remained independent of response (p > 0.4). These data demonstrate that s.c. rIL-2 and s.c. rIFN-alpha produce a significant increase in peripheral blood NK cells; this expansion correlates significantly with treatment response in advanced tumor patients receiving long-term combination immunotherapy at outpatient doses.

Lack of therapeutic efficacy of tamoxifen in advanced renal cell carcinoma.

In the present study, we treated a total of 62 patients with advanced renal cell carcinoma with high-dose tamoxifen (100 mg/m2/day). Patients were treated in the outpatient setting, and were evaluated 8-12 weeks after initiation of therapy or sooner, when clinical disease progression was evident; a total of 15 patients were seen at short regular intervals for evaluation of clinical and laboratory parameters. Of these 62 patients, 59 were evaluable for treatment response, survival and systemic toxicity. One partial remission was achieved (1.7%; 95% confidence interval, 0.04-9.09%), response duration was 3 months. 10 patients presented with stable disease, for a median duration of 4.0 months, and 48 patients exhibited disease progression upon and after therapy. Systemic toxicity was significant; severe fatigue occurred in 5% of patients, and moderate anaemia, dyspnea, alopecia and malaise in almost 20% of patients. Antineoplastic efficacy of tamoxifen at this dosage in this cohort of patients was at best marginal and well in the range associated with the occurrence of spontaneous remissions. Toxicity was substantial, and it was not balanced by therapeutic benefit. This is consistent with the known lack of therapeutic efficacy of endocrine therapy in advanced renal cell carcinoma.

Low-Dose lnterleukin-2 in Combination with Interferon-α Effectively Modulates Biological Response in vivo

Phenotypic characterization of peripheral blood lymphocytes was performed in patients with advanced metastatic cancer receiving low-dose recombinant interleukin-2 (rIL-2) and recombinant interferon-α

Treatment of Metastatic Colorectal Cancer Patients with 5-Fluorouracil in Combination with Recombinant Subcutaneous Human lnterleukin-2 and Alpha-lnterferon

We treated 14 patients with progressive metastatic colorectal cancer, using a combination of subcutaneous recombinant human interleukin-2 (4.8 x 10(6) IU/m2 three times daily on days 1 and 22, and twice daily on days 2 and 23, followed by 2.4 x 10(6) IU/m2 twice daily on days 3-5, 8-12, 24-26, and on 5 consecutive days per week, starting day 29), recombinant human interferon-alpha 2a (5.0 x 10(6) U/m2 thrice weekly), and 5-fluorouracil (750 mg/m2 i.v. bolus on days 15-19, and at weekly intervals thereafter, with a 1-week off-therapy interval every 4 weeks). Therapy was continued until disease progression occurred. Four (29%) and 8 (57%) evaluable patients achieved partial remission and stable disease, respectively; median response duration was 5.9 months. Toxicity of this regimen was moderate; the most common side effects were thrombocytopenia, leukopenia, nausea/vomiting, anorexia, malaise and fevers in all patients, along with diarrhea (63%) and mucositis (54%). Less than 10% of patients developed WHO grade IV toxicity; no toxic deaths occurred. Efficacy of this combination was not substantially different from alternative 5-fluorouracil-based regimens.