Results of 20- versus 45-min post-infusion scalp cooling time in the prevention of docetaxel-induced alopecia.

PURPOSE: For patients, chemotherapy-induced alopecia (CIA) is one of the most distressing side effects of treatment. Scalp cooling can prevent or minimise CIA; the results may depend on the duration of cooling. Since a previous study on post-infusion cooling time in patients treated with docetaxel chemotherapy found no difference between 90 and 45 min, we investigated whether hair-preserving results could be maintained with a shorter post-infusion cooling time. METHODS: In this prospective, multi-centre randomised study, 134 patients who started treatment with docetaxel 75-100 mg/m(2) in a 3-weekly schedule were randomly assigned in a 1:1 ratio to a post-infusion cooling time of 45 or 20 min. The primary end point was the need for a wig or other head covering as assessed by the patient. A visual analogue scale (VAS) with a range from 0 (not tolerable) to 10 (very tolerable) was used to measure tolerance. RESULTS: Scalp cooling results were similar for 45- and 20-min post-infusion cooling times. Thirty-three out of 45 patients (73 %) treated with 20 min of post-infusion cooling did not need a form of head covering, compared with 41 out of 52 patients (79 %) treated with 45 min of post-infusion cooling (p = 0.5). The procedure was well tolerated (mean visual analogue score 8.3). Six patients stopped due to intolerance during the first treatment cycle. CONCLUSIONS: A 20-min post-infusion cooling time is effective and tolerable for patients treated with scalp cooling to prevent docetaxel-induced alopecia. TRIAL REGISTRATION: Trialregister.nl Identifier, NTR 1856.

The influence of prior novel androgen receptor targeted therapy on the efficacy of cabazitaxel in men with metastatic castration-resistant prostate cancer.

INTRODUCTION: The treatment armamentarium for metastatic castration-resistant prostate cancer (mCRPC) has expanded with the introduction of several new therapies. In this treatment continuum, it is unclear whether the efficacy of cabazitaxel is affected by prior novel androgen receptor targeted therapies (ART) such as abiraterone and enzalutamide. In this study, we investigated the influence of prior ART on the efficacy of cabazitaxel in men with mCRPC. PATIENTS AND METHODS: Data from an ongoing multicentre, phase II trial were used comprising 114 men with mCRPC treated with cabazitaxel in the post-docetaxel setting. The primary endpoints of the current analysis were prostate-specific antigen (PSA) response (⩾ 50%), and overall survival (OS). Univariate and multivariable analyses were conducted to investigate the influence of prior ART on the efficacy of cabazitaxel. RESULTS: From the 114 patients included in this analysis, 44 men received prior ART and 70 men did not receive prior ART before treatment with cabazitaxel. PSA response rates while on cabazitaxel treatment were similar in patients with and without prior ART (34% versus 40%, respectively, P = 0.53). Likewise, median OS was not significantly different between men with and without prior ART (13.0 versus 14.0 months, respectively, logrank P = 0.65). In multivariable analysis, the only variables significantly associated with OS were performance status, serum albumin and alkaline phosphatase. CONCLUSION: Our study showed that prior treatment with ART may not influence the efficacy of cabazitaxel in men with mCRPC. With emerging evidence of cross-resistance in the treatment of mCRPC, cabazitaxel provides a good treatment option irrespective of prior ART.

Long-term results of a randomised phase III trial of weekly versus three-weekly paclitaxel/platinum induction therapy followed by standard or extended three-weekly paclitaxel/platinum in European patients with advanced epithelial ovarian cancer.

BACKGROUND: Weekly paclitaxel/carboplatin might improve survival in platinum-resistant epithelial ovarian cancer (EOC). We compared efficacy of first-line weekly to three-weekly paclitaxel/cis- or carboplatin (PCw and PC3w) induction therapy, followed by either three or six PC3w cycles. PATIENTS AND METHODS: In this multicentre, randomised phase III trial with 2×2 design, patients with FIGO stage IIb-IV EOC were randomised to six cycles PCw (paclitaxel 90mg/m(2), cisplatin 70mg/m(2) or carboplatin AUC 4) or three cycles PC3w (paclitaxel 175mg/m(2), cisplatin 75mg/m(2) or carboplatin AUC 6), followed by either three or six cycles PC3w. Primary endpoints were progression free survival (PFS) and overall survival (OS). Secondary endpoints were response rate (RR) and toxicity. RESULTS: Of 267 eligible patients, 133 received PCw and 134 PC3w. The first 105 patients received cisplatin, after protocol amendment the subsequent 162 patients received carboplatin. Weekly cisplatin was less well tolerated than weekly carboplatin. All PC3w cycles were well tolerated. At the end of all treatments, RR was 90.8% with no differences between the treatment arms. After a follow-up of median 10.3years (range 7.1-14.8), median PFS was 18.5 (95% confidence interval (CI) 15.9-21.0) months for PCw and 16.4 (95% CI 13.5-19.2) months for PC3w (p=0.78). Median OS was 44.8 (95% CI 33.1-56.5) months for PCw and 41.1 (95% CI 34.4-47.7) months for PC3w (p=0.98). CONCLUSIONS: There was no benefit in terms of OS, PFS or RR for a weekly regimen nor for extended chemotherapy as first-line treatment for EOC in European patients.

Assessing health-state utility values in patients with metastatic colorectal cancer: a utility study in the United Kingdom and the Netherlands.

PURPOSE: This study aimed to elicit EuroQol Quality of Life 5-Dimensions (EQ-5D) utility values from patients with second-line metastatic colorectal cancer (mCRC) pre- and post-progression. METHODS: A cross-sectional study was conducted in five hospitals in the Netherlands and the UK. Patients with mCRC were eligible if prescribed a second or subsequent line of therapy or best supportive care (BSC), received prior oxaliplatin in first-line therapy, and had Eastern Cooperative Oncology Group (ECOG) performance status scores of 0-2 at second-line initiation. Patients completed the EuroQol Quality of Life 5-Dimensions 3-levels (EQ-5D-3L) questionnaire and were categorized as pre- or post-progression. Chart data including patient demographics, clinical history, prior/current treatments and serious adverse events (SAEs) were collected. Mean utilities were estimated; uni- and multivariate analyses were conducted. RESULTS: Seventy-five patients were enrolled; 42 were pre-progression defined as second line or third line following an AE on second line and 33 were post-progression defined as third or subsequent therapy lines or BSC. Patient/disease characteristics and number of SAEs were similar between cohorts. Mean utility scores were 0.741 (SD = 0.230) and 0.731 (SD = 0.292) for pre- and post-progression cohorts, respectively. Compared to pre-progression, more patients reported increased anxiety/depression (36 vs. 12 %) and fewer problems with daily activities (64 vs. 38 %) post-progression. More patients pre-progression were on active treatment at enrolment (83 vs. 42 %) compared to post-progression. CONCLUSIONS: This is the first real-world study to collect utilities for patients with second-line mCRC pre- and post-disease progression. Utility values were similar pre- and post-progression. To further explore the effect of radiological progression on utilities, longitudinal research is required that includes patients in palliative care centres.

Reduced risk of distant recurrence after adjuvant chemotherapy in patients with stage III colon cancer aged 75 years or older.

BACKGROUND: Little is known about the effects of adjuvant chemotherapy on the risk of distant recurrence in elderly with stage III colon cancer, treated in daily practice. PATIENTS AND METHODS: One thousand two hundred and ninety-one stage III colon cancer patients diagnosed in the southern Netherlands between 2003 and 2008 were included. Propensity score matching was applied to create a subsample to reduce bias caused by differences between patients receiving adjuvant chemotherapy and patients not receiving adjuvant chemotherapy. For both the total study population and the propensity score matched sample, Cox regression analysis was used to discriminate independent risk factors for distant recurrence. RESULTS: Adjuvant chemotherapy (CT) was correlated with a reduced risk of distant recurrence in both the total study population [hazard ratio (HR) CT versus nCT 0.55, 95% confidence interval (CI) 0.42-0.70] and in the propensity score matched sample (HR CT versus nCT 0.46, 95% CI 0.33-0.63). In separate analyses for patients aged <75 and ≥75 years, the effect of adjuvant chemotherapy on the risk of distant recurrence remained comparable for both age groups (HR CT versus nCT 0.50, 95% CI 0.37-0.68 and 0.57, 95% CI 0.36-0.90, respectively). CONCLUSION: Distant recurrence risks at higher age definitely warrant consideration of adjuvant chemotherapy for elderly stage III colon cancer patients. This decision should be based on a multidisciplinary and functional assessment of the patient, not on age.

The influence of age and co-morbidity on treatment and prognosis of ovarian cancer: a population-based study.

OBJECTIVES: With the rising mean age, more patients will have one or more other serious diseases at the time of diagnosis of ovarian cancer (co-morbidity). In this study, the independent effects of age and co-morbidity on the application of treatment guidelines and prognosis were evaluated. METHODS: All patients with epithelial ovarian cancer diagnosed between 1995 and 2001 in the southern part of The Netherlands (N = 1116) were included. RESULTS: The prevalence of co-morbidity increased from 34% of the age group <70 to 63% of the older age group. Eighty-three percent of the patients with FIGO stage II or stage III younger than 70 years underwent the advised treatment (combination of surgery and chemotherapy) compared to only 45% of the patients aged 70 or older. In a multivariable analysis age, FIGO stage, presence of co-morbidity, and year of diagnosis seemed to be independent predictors of receiving the advised treatment. In multivariable analyses age 70 + (HR = 1.3, 95% CI = 1.03-1.7) and the use of both surgery and chemotherapy (HR = 0.4, 95% CI = 0.3-0.6, reference is only surgery) were independent prognostic factors for overall survival. CONCLUSIONS: Even in the absence of co-morbidity, standard combination therapy was prescribed significantly less often for elderly patients with FIGO II or III ovarian cancer. Age and combined treatment of surgery and platinum-based chemotherapy were independent prognostic factors. Co-morbidity did not seem to have a prognostic effect.

Duodenal metastasis: an uncommon cause of occult small intestinal bleeding.

Duodenal metastases are a very uncommon and peculiar cause of upper gastrointestinal bleeding. However, they should be considered in a patient presenting with upper gastrointestinal bleeding and a previous history of malignancy. The importance of recognising the unusual presentation of duodenal metastasis has to be emphasised. We describe two patients with upper gastrointestinal bleeding due to duodenal metastases. In the first patient a periampullary bleeding due to a metastasis of a renal cell carcinoma was detected five years after nephrectomy of the right kidney. In the second patient an occult bleeding caused by a duodenal metastasis of a melanoma was diagnosed. The first manifestation of this melanoma was eight years earlier.

Phase I and pharmacologic study of the arotinoid Ro 40-8757 in combination with cisplatin and etoposide in patients with non-small cell lung cancer.

This phase I study was performed to assess the feasibility of combining cisplatin/etoposide (VP-16) with the arotinoid Ro 40-8757 and to determine the dose-limiting toxicity (DLT) of Ro 40-8757 in this combination. Patients with non-small cell lung cancer were eligible. Treatment consisted of Ro 40-8757 p.o. day 1-21, cisplatin 100 mg/m2 i.v. on day 2 and VP-16 100 mg/m2 i.v. on day 2-4, repeated every 3 weeks. Eighteen patients were evaluable for toxicity and response. The doses of Ro 40-8757 ranged from 84 mg/m2 once daily to 42 mg/m2 thrice daily (tid). DLT consisting of delayed nausea/vomiting was reached at 42 mg/m2 tid. Consequently, the maximum tolerated dose was set at one dose level below the DLT, i.e. 28 mg/m2 tid. Skin toxicity occurred but was well manageable. Pharmacological analyses showed a small increase in the volume of distribution of cisplatin and VP-16 between the first and third course. However, no relationship with side effects was found. A response was achieved in 50% of patients. The combination of cisplatin/VP-16 with Ro 40-8757 appears to be feasible at a dose schedule of 28 mg/m2 tid. The response rate was at the upper rate of what can be expected with cisplatin and VP-16.

Results of interleukin-2-based treatment in advanced melanoma: a case record-based analysis of 631 patients.

PURPOSE: In patients with stage IV melanoma, durable responses have been reported with treatment regimens that involve high-dose interleukin-2 (IL-2). We analyze long-term results of 631 melanoma patients from 12 institutions who had received IL-2 alone, in combination with interferon alfa 2a or 2b (IFNalpha), or with cytotoxic drugs. METHODS: Case records that contained pretreatment parameters, response data, and updated survival information were collected. After univariate analysis, the multivariate evaluation of the impact of pretreatment parameters on response and survival was performed by logistic regression and Cox's regression, respectively. RESULTS: Patients were divided into four groups according to treatment: IL-2 alone (n=117), IL-2 and chemotherapy (n=49), IL-2 and IFNalpha (n=153), and IL-2, chemotherapy, and IFNalpha (n=312). The median survival of all patients was 10.5 months and the 2- and 5-year survival rates were 19.9% and 10.4%, respectively. Independent prognostic factors for response and survival were entirely different, treatment group being the only significant factor for response, and serum lactate dehydrogenase (LDH), metastatic site, and performance predicting survival. The addition of IFNalpha to IL-2 was associated with prolonged survival, but the effect of additional chemotherapy was less obvious. CONCLUSION: Serum LDH, metastatic site, and performance status are useful stratification factors for randomized trials in metastatic melanoma. The improved long-term survival rates observed in melanoma patients treated with IL-2/IFNalpha-containing regimens are notable in contrast to the reported 5-year survival rates of 2% to 6% achieved with chemotherapy, but because selection bias cannot be ruled out, the impact of IL-2, as well as all other components of the treatment regimens, on survival needs to be confirmed in prospective randomized trials.

High-dose regimen of interleukin-2 and interferon-alpha in combination with lymphokine-activated killer cells in patients with metastatic renal cell cancer.

Seventy-two patients with metastatic renal cell cancer were treated with the combination of high-dose interleukin-2 (IL2), interferon-alpha (IFN alpha), and lymphokine-activated killer cells (LAK). Seventeen patients were entered in a feasibility part of the study (protocol 1) and 55 in an efficacy part (protocol 2). Protocol 2 differed from protocol 1 in the addition of IFN alpha to the first 5 days of IL2 infusion. Each patient was planned to receive two induction cycles. IL2, 18 MIU/m2/day, was administered continuously i.v. on days 1-5, and IFN alpha, 5 MIU/m2/day (protocol 2), was administered i.m. on days 1-5, followed by three daily lymphaphereses on days 7-9. On day 12, treatment was resumed with IL2 and IFN alpha on days 12-15 and LAK reinfusions on days 12-14. In protocol 1, three complete (CR) and one partial (PR) responses were achieved (response rate 24%). The median duration of response and the median survival were 18.1 and 13.9 months, respectively. The 3-year survival was 35%. Of the 51 evaluable patients in protocol 2, 6 achieved a CR and 13 a PR (response rate 37%). The median duration of response was 11.1 months. The median survival was 16.9 months. The 3-year survival was 35%. There were three treatment-related deaths. Other severe toxicities included hypotension, cardiotoxicity, pulmonary edema, renal toxicity, and infectious complications. In the two induction cycles, only 54 and 42% of the planned doses could be administered. We conclude that the use of high-dose regimens of IL2 and IFN alpha is not warranted, unless we can define more accurately which patients may experience long-term survival as a result of treatment.

Interferon alfa-2a and interleukin-2 with or without cisplatin in metastatic melanoma: a randomized trial of the European Organization for Research and Treatment of Cancer Melanoma Cooperative Group.

PURPOSE: The combination of interferon alfa-2a (IFN alpha) and high-dose interleukin-2 (IL-2) is active in metastatic melanoma. The addition of cisplatin (CDDP) has resulted in response rates greater than 50%. This study was performed to determine whether the addition of CDDP to a cytokine treatment regimen with IFN alpha and high-dose IL-2 influences survival of patients with metastatic melanoma. PATIENTS AND METHODS: Patients with advanced metastatic melanoma were randomly assigned to receive treatment with IFN alpha 10 x 10(6) U/m2 subcutaneously on days 1 through 5 and a high-dose intravenous decrescendo regimen of IL-2 on days 3 through 8 (18 mIU/ m2/6 hours, 18 mIU/m2/12 hours, 18 mIU/m2/24 hours, and 4.5 mIU/m2/24 hours x 3) without (arm A) or with (arm B) CDDP 100 mg/m2 on day 1. Treatment cycles were repeated every 28 days to a maximum of four cycles. RESULTS: One hundred thirty-eight patients with advanced metastatic melanoma, of whom 87% had visceral metastases, were accrued for the trial. Both regimens were feasible in a multicenter setting. The objective response rate was 18% without and 33% with CDDP (P = .04). The progression-free survival was 53 days without and 92 days with CDDP (P = .02, Wilcoxon; P = .09, log-rank). There was no statistically significant difference in survival between treatment arms, with a median overall survival duration for all patients of 9 months. CONCLUSION: The addition of CDDP to cytokine treatment with IFN alpha and IL-2 does not influence survival of patients with advanced metastatic melanoma, despite a significant increase in response rate and progression-free survival.

Tunnelled central venous catheters yield a low incidence of septicaemia in interleukin-2-treated patients.

A retrospective study on the incidence of catheter-related complications and catheter indwelling time (tCI) during treatment with continuous interleukin-2 (IL-2) infusion in patients with metastatic renal cell cancer, who were equipped with tunnelled central venous catheters (CVC). A group of 72 patients were treated with IL-2-based immunotherapy. Two induction treatment cycles of 35 days each were used. Treatment consisted of IL-2 as a continuous intravenous infusion (c.i.v.) with lymphokine-activated killer cells and interferon alpha intramuscularly. A tunnelled CVC was inserted at the start of treatment and was kept in place for the duration of the therapy or until the occurrence of complications. Out of 72 CVC, 30 (42%) functioned uneventfully for a median tCI of 64 days. In another 12 clinically uncomplicated cases (16%), catheter tips were positive in routine culture after a median tCI of 33 days. In 18 patients (25%), CVC-related infections were noted, including 8 (11%) local tunnel infections and 10 (14%) septic episodes. These complications occurred at a median tCI of 28 and 20 days respectively. In 15 (83%) of these 18 catheter infections, Staphylococcus aureus was isolated, whereas in the remaining 3 (17%) Staphylococcus epidermidis was found. Subclavian vein thrombosis was noted in 12 (17%) CVC at a median tCI of 31 days: 5 (36%) of these were diagnosed in the first 14 patients. This prompted us to administer prophylactic heparin 15,000 i.u. c.i.v. daily during IL-2 treatment. Thereafter the incidence of thrombosis dropped to 7 (12%) in the subsequent 58 CVC inserted (P = 0.03). In conclusion, in contrast to previous reports on the high incidence of CVC-related septicaemia and thrombosis, we observed a relatively low incidence of these complications, which we ascribe to the use of tunnelled catheters and prophylactic heparin.

Interleukin 2 and interferon alpha-2a do not improve anti-tumour activity of 5-fluorouracil in advanced colorectal cancer.

Treatment using a combination of 5-fluorouracil (5-FU), interferon-alpha (IFN alpha-2a) and interleukin 2 (IL-2) has been shown to mediate disease regression in selected patients with advanced colorectal cancer. This phase II study was designed to evaluate the anti-tumour activity and toxicity of the combination of IL-2, IFN alpha-2a and 5-FU in patients with advanced colorectal cancer. Forty-four patients with metastatic colorectal cancer were treated, predominantly on an outpatient basis, with subcutaneous IFN alpha-2a and IL-2 three times per week followed by once a week bolus intravenous 5-FU injections. There were six (14%) partial responses among the 43 evaluable patients [95% confidence interval (CI) 5-28%]. Twenty-four patients had stable disease (56%) and 13 patients (30%) showed progressive disease. The median time to progressive disease in 43 patients was 19 weeks (range 2-72 weeks) and in responders 34 weeks (range 24-30 weeks). The median overall survival was 47 weeks (range 2-85 weeks) and in responders 60 weeks (range 35-71 weeks). Treatment-related toxic effects included fatigue, nausea and vomiting. Granulocytopenia was the main reason for the dose reductions or treatment interruptions in 32 out of 44 patients. One patient died of toxicity due to renal failure. Serial assessments of immunophenotyping and cytolytic activities of peripheral blood lymphocytes did not show changes in the numbers of circulating natural killer (NK) cells or in the levels of NK and lymphokine-activated killer (LAK) cytolytic activities. This regimen of IL-2 and IFN alpha-2a with 5-FU has only modest anti-tumour activity in advanced colorectal cancer.

Phase II study of a short course of weekly high-dose cisplatin combined with long-term oral etoposide in metastatic malignant melanoma.

The results of cytostatic therapy in metastatic melanoma are very disappointing. In phase II studies with high-dose cisplatin regimens, a remarkably high response rate was observed. In a phase I study with a short course of weekly cisplatin, combined with oral etoposide, we were able to reach, in most patients, a cisplatin dose intensity of 60 mg/m2/week. We performed a phase II study with this schedule in metastatic malignant melanoma. 15 consecutive patients were entered in the study. Treatment consisted of cisplatin 70 mg/m2 on days 1, 8, 15 and days 29, 36, 43 combined with oral etoposide 50 mg daily, days 1-15 and days 29-43. Patients with a response or stable disease continued treatment with oral etoposide 50 mg/m2 daily, days 1-21 every 4 weeks. All patients were evaluable for response and toxicity. The majority of the patients received six cycles of cisplatin with the planned cisplatin dose intensity of 60 mg/m2/week. A partial response was observed in 2 patients (13%; 95% confidence interval (CI) 2-44%) of, respectively, 22 and 12 weeks; stable disease was observed in 6 patients. Toxicity consisted mainly of alopecia and bone marrow suppression. 4 patients had tinnitus, one patient had neurotoxicity grade 1. The regimen studied has only limited activity in metastatic melanoma in spite of the high-dose intensity of cisplatin reached with this schedule.

Dose efficacy study of two schedules of high-dose bolus administration of interleukin 2 and interferon alpha in metastatic melanoma.

Forty-three patients with metastatic melanoma were treated with a 5 day (18 patients) and a 3 day (25 patients) schedule of high-dose IL-2 11.7 MIU m2 and IFN-alpha 3 MIU m2 i.v. by bolus administration every 8 h, repeated every 21 days for a total of three courses. The 5 day schedule resulted in a high response rate of 41% (CI 18-67%), but was accompanied by severe cardiotoxicity (41%) and central nervous system toxicity (28%). The 3 day schedule was associated with manageable toxicity, but yielded a moderate response rate of 20% (CI 7-43%).

Modulation of immune parameters in patients with metastatic renal-cell cancer receiving combination immunotherapy (IL-2, IFN alpha and autologous IL-2-activated lymphocytes).

We treated 72 patients with metastatic renal-cell cancer according to 2 protocols consisting of two 5-week induction cycles of continuous i.v. high-dose interleukin-2 (IL-2), i.m. interferon-alpha (IFN alpha) and ex vivo IL-2-activated lymphocytes, followed for patients with stable disease (SD), partial response (PR) or complete response (CR) by four 4-week maintenance cycles of IL-2 and IFN alpha. Protocol 2 (55 patients) differed from protocol 1 (17 patients) in (i) the addition of IFN alpha to the first IL-2 infusions in both induction cycles; (ii) the use of Teceleukin IL-2, reconstituted with carrier protein, instead of Proleukin IL-2 without carrier protein. We classified 23 patients with CR and PR as responders (4 in protocol 1 and 19 in protocol 2) and 45 patients with SD and progressive disease as non-responders. Prior to immunotherapy, patients entered into protocol 2 already had higher IFN gamma serum concentrations, higher peripheral blood CD56-,3+ and CD8-,4+ lymphocyte numbers and lower NKK562 activity than those entered into protocol 1. These differences persisted during and after immunotherapy. In line with these observations, ex vivo IL-2-activated lymphocytes had larger proportions of CD56-,3+ and CD8-,4+ lymphocytes and lower NKK562 activity in protocol 2 than in protocol 1. Higher IL-2 serum concentrations were reached during the IL-2 infusion in protocol 2 than in protocol 1. In addition, the immunomodulation in protocol 2 was stronger than in protocol 1 as indicated by higher TNF alpha serum concentrations and a more pronounced eosinophilia. Differences between responders and non-responders treated according to the 2 protocols were not significant, except for the total number of lymphocytes obtained by apheresis, which was higher in responders than in non-responders.

Intrapleural administration of interleukin 2 in pleural mesothelioma: a phase I-II study.

Twenty-three patients with pleural mesothelioma stage I-IIA were entered in a study of continuous daily intrapleural infusion of interleukin 2 (IL-2) for 14 days, repeated every 4 weeks. IL-2 was administered according to a groupwise dose escalation schedule (group A, 3 x 10(4); group B, 3 x 10(5); group C, 3 x 10(6); group D, 6 x 10(6); group E, 18 x 10(6); and group F, 36 x 10(6) IU day-1). Each group consisted of at least three patients. Intrapleural administration of IL-2 was associated with acceptable toxicity. All patients were treated on an outpatient basis except for the patients at dose levels E and F. Dose-limiting toxicity was observed at level F, 36 x 10(6) IU daily, and consisted of catheter infection, fever and flu-like symptoms. Intrapleural IL-2 levels were high (> 20,000 IU ml-1) at levels E and F, while serum levels in most patients were not or barely detectable (< 3-30 IU ml-1). Intrapleural IL-2 levels were up to 6000-fold higher than systemic levels. Intrapleural tumour necrosis factor alpha (TNF-alpha) levels varied greatly and did not correlate with IL-2 dosage. Intrapleural mononuclear cells (MNCs) displayed IL-2-induced lymphokine-activated killer (LAK) activity in all patients. Two patients were not evaluable for response owing to catheter-related problems which precluded the delivery of IL-2. Partial response (PR) occurred in 4 of 21 evaluable patients (19%; 95% confidence interval 5-42%) with a median time to progression of 12 months (range 5-37). Stable disease (SD) occurred in seven patients with a median time to progression of 5 months (range 2-7). There were no complete responses (CRs). The median overall survival was 15.6 months (range 3.0-43). No relationship between the dose of IL-2 and response rate was observed. We conclude that IL-2 given intrapleurally is accompanied with acceptable toxicity and has anti-tumour activity against mesothelioma. In view of the refractory nature of the disease IL-2 may be a treatment option for mesothelioma. A formal phase II study is warranted. Based on the observed toxicity, the lack of dose-response relationship and the immunomodulatory effects seen at relatively low-dose IL-2, the recommended dose for a phase II study is 3 x 10(6) IU day-1 using the present treatment schedule.