Prognostic significance of absolute lymphocyte count in patients with metastatic renal cell carcinoma receiving first-line combination immunotherapies: results from the International Metastatic Renal Cell Carcinoma Database Consortium.

BACKGROUND: Lymphocytes are closely linked to mechanisms of action of immuno-oncology (IO) agents. We aimed to assess the prognostic significance of absolute lymphocyte count (ALC) in patients with metastatic renal cell carcinoma (mRCC). PATIENTS AND METHODS: Using the International mRCC Database Consortium (IMDC), patients receiving first-line IO-based combination therapy were analysed. Baseline patient characteristics, objective response rates (ORRs), time to next treatment (TTNT), and overall survival (OS) were compared. RESULTS: Of 966 patients included, 195 (20%) had lymphopenia at baseline, and they had a lower ORR (37% versus 45%; P < 0.001), shorter TTNT (10.1 months versus 24.3 months; P < 0.001), and shorter OS (30.4 months versus 48.2 months; P < 0.001). Among 125 patients with lymphopenia at baseline, 52 (42%) experienced ALC recovery at 3 months, and they had longer OS (not reached versus 30.4 months; P = 0.012). On multivariable analysis for OS, lymphopenia was an independent adverse prognostic factor (hazard ratio 1.68; P < 0.001). Incorporation of lymphopenia into the IMDC criteria improved OS prediction accuracy (C-index from 0.688 to 0.707). CONCLUSIONS: Lymphopenia was observed in one-fifth of treatment-naive patients with mRCC and may serve as an indicator of unfavourable oncologic outcomes in the contemporary IO era.

Impact of comorbidity on renal cell carcinoma prognosis: a nationwide cohort study.

BACKGROUND: Presence of comorbid diseases at time of cancer diagnosis may affect prognosis. We evaluated the impact of comorbidity on survival of patients diagnosed with renal cell carcinoma (RCC), overall and among younger (<70 years) and older (≥70 years) patients. METHODS: We established a nationwide register-based cohort of 7894 patients aged ≥18 years diagnosed with RCC in Denmark between 2006 and 2017. We computed 1- and 5-year overall survival and hazard ratios (HRs) for death according to the Charlson Comorbidity Index (CCI) score. RESULTS: Survival decreased with increasing CCI score despite an overall increase in survival over time. The 5-year survival rate of patients with no comorbidity increased from 57% among those diagnosed in 2006-2008 to 69% among those diagnosed in 2012-2014. During the same periods, the survival rate increased from 46% to 62% among patients with a CCI score of 1-2 and from 39% to 44% for those with a CCI score of ≥3. Patients with CCI scores of 1-2 and ≥3 had higher mortality rates than patients with no registered comorbidity (HR 1.15, 95% CI 1.06-1.24 and HR 1.56, 95% CI 1.40-1.73). Patterns were similar for older and younger patients. Particularly, diagnoses of liver disease (HR 2.09, 95% CI 1.53-2.84 and HR 4.01, 95% CI 2.44-6.56) and dementia (HR 2.16, 95% CI 1.34-3.48) increased mortality. CONCLUSION: Comorbidity decreased the survival of patients with RCC, irrespective of age, despite an overall increasing survival over time. These results highlight the importance of focusing on comorbidity in this group of patients.

Real-world outcomes of nivolumab and cabozantinib in metastatic renal cell carcinoma: results from the International Metastatic Renal Cell Carcinoma Database Consortium.

Objectives: In the present study, we explored the real-world efficacy of the immuno-oncology checkpoint inhibitor nivolumab and the tyrosine kinase inhibitor cabozantinib in the second-line setting. Methods: Using the International Metastatic Renal Cell Carcinoma Database Consortium (imdc) dataset, a retrospective analysis of patients with metastatic renal cell carcinoma (mrcc) treated with nivolumab or cabozantinib in the second line after prior therapy targeted to the vascular endothelial growth factor receptor (vegfr) was performed. Baseline characteristics and imdc risk factors were collected. Overall survival (os) and time to treatment failure (ttf) were calculated using Kaplan-Meier curves. Overall response rates (orrs) were determined for each therapy. Multivariable Cox regression analysis was performed to determine survival differences between cabozantinib and nivolumab treatment. Results: The analysis included 225 patients treated with nivolumab and 53 treated with cabozantinib. No significant difference in median os was observed: 22.10 months [95% confidence interval (ci): 17.18 months to not reached] with nivolumab and 23.70 months (95% ci: 15.52 months to not reached) with cabozantinib (p = 0.61). The ttf was also similar at 6.90 months (95% ci: 4.60 months to 9.20 months) with nivolumab and 7.39 months (95% ci: 5.52 months to 12.85 months) with cabozantinib (p = 0.20). The adjusted hazard ratio (hr) for nivolumab compared with cabozantinib was 1.30 (95% ci: 0.73 to 2.3), p = 0.38. When adjusted by imdc criteria and age, the hr was 1.32 (95% ci: 0.74 to 2.38), p = 0.35. Conclusions: Real-world imdc data indicate comparable os and ttf for nivolumab and cabozantinib. Both agents are reasonable therapeutic options for patients progressing after initial first-line vegfr-targeted therapy.

Adjuvant sunitinib in patients with high-risk renal cell carcinoma: safety, therapy management, and patient-reported outcomes in the S-TRAC trial.

Background: Adjuvant sunitinib has significantly improved disease-free survival versus placebo in patients with renal cell carcinoma at high risk of recurrence post-nephrectomy (hazard ratio 0.76; 95% confidence interval, 0.59-0.98; two-sided P = 0.03). We report safety, therapy management, and patient-reported outcomes for patients receiving sunitinib and placebo in the S-TRAC trial. Patients and methods: Patients were stratified by the University of California, Los Angeles Integrated Staging System and Eastern Cooperative Oncology Group performance status score, and randomized (1 : 1) to receive sunitinib (50 mg/day) or placebo. Single dose reductions to 37.5 mg, dose delays, and dose interruptions were used to manage adverse events (AEs). Patients' health-related quality of life, including key symptoms typically associated with sunitinib, were evaluated with the European Organisation for Research and Treatment of Cancer Quality of Life Questionnaire (EORTC QLQ-C30). Results: Patients maintained treatment for 9.5 (mean, SD 4.4) and 10.3 (mean, SD 3.7) months in the sunitinib and placebo arms, respectively. In the sunitinib arm, key AEs occurred ∼1 month (median) after start of treatment and resolved within ∼3.5 weeks (median). Many (40.6%) AEs leading to permanent discontinuation were grade 1/2, and most (87.2%) resolved or were resolving by 28 days after last treatment. Patients taking sunitinib showed a significantly lower EORTC QLQ-C30 overall health status score versus placebo, although this reduction was not clinically meaningful. Patients reported symptoms typically related to sunitinib treatment with diarrhea and loss of appetite showing clinically meaningful increases. Conclusions: In S-TRAC, AEs were predictable, manageable, and reversible via dose interruptions, dose reductions, and/or standard supportive medical therapy. Patients on sunitinib did report increased symptoms and reduced HRQoL, but these changes were generally not clinically meaningful, apart from appetite loss and diarrhea, and were expected in the context of known sunitinib effects. Clinical trial registration: ClinicalTrials.gov, NCT00375674.

Hyponatremia associates with poor outcome in metastatic renal cell carcinoma patients treated with everolimus: prognostic impact.

BACKGROUND: The prognostication of metastatic renal cell carcinoma (mRCC) is based on Memorial Sloan Kettering Cancer Center (MSKCC) and International Metastatic Renal Cell Carcinoma Database Consortium (IMDC) risk classifications. Research has shown that hyponatremia is associated with worse prognosis in cancer. We analyzed the association of hyponatremia and outcome in everolimus-treated mRCC patients. PATIENTS AND METHODS: Baseline and on-treatment (≤12 weeks) sodium in 233 mRCC patients was analyzed using Kaplan-Meier, Cox regression and logistic regression. Baseline sodium was correlated with baseline thrombocyte and neutrophil values. RESULTS: 65 (28%) and 41 (18%) patients had sodium < lower limit of normal (LLN) at baseline and on-treatment, respectively. Baseline sodium < LLN was associated with shorter overall survival (OS) (6.1 vs. 10.3 months; p < .001) and progression-free survival (PFS) (2.8 vs. 3.5 months; p = .04). On-treatment sodium < LLN was associated with shorter OS (5.4 vs. 9.9 months; p < .001) and PFS (2.8 vs. 4.0 months; p < .001). In multivariate analyses adjusted for IMDC factors, baseline and on-treatment sodium < LLN were significantly associated with shorter OS (adjusted HR 1.46 (95% CI 1.04-2.05); p = .02; adjusted HR 1.80 (95% CI 1.23-2.61); p = .002; respectively). On-treatment sodium < LLN was significantly associated with progressive disease (OR 0.23 (95% CI 0.10-0.56); p = .001). A landmark analysis demonstrated that on-treatment hyponatremia was significantly associated with shorter OS and PFS (p = .01 and p = .03, respectively). On-treatment normalization of hyponatremia was associated with improved OS (unadjusted HR 0.61 (95% CI 0.35-0.98); p = .04), as compared to patients with sustained hyponatremia throughout follow-up. CONCLUSIONS: Hyponatremia associates with poor outcome in mRCC patients treated with everolimus. On-treatment normalization of hyponatremia to normal sodium values associates with favorable outcome.

Everolimus-induced pneumonitis associates with favourable outcome in patients with metastatic renal cell carcinoma.

BACKGROUND: Mammalian target of rapamycin inhibitors may induce pneumonitis. We analysed the association of pneumonitis with outcomes in everolimus treated metastatic renal cell carcinoma (mRCC) patients. PATIENTS AND METHODS: Eighty-five mRCC patients received everolimus at Helsinki University Hospital (cohort A). Computed tomography (CT) verified pneumonitis was correlated with outcome using Kaplan-Meier, Cox regression and logistic regression. An independent cohort of 148 everolimus treated mRCC patients (cohort B) at Aarhus University Hospital was assessed for validation. RESULTS: In cohort A, CT-verified pneumonitis (N = 29, 34.1%) was associated with improved overall survival (OS) (24.7 versus 8.5 months; P < 0.001), progression-free survival (PFS) (5.5 versus 3.2 months; P = 0.002) and clinical benefit rate (CBR) 57.1% versus 24.1% (P = 0.003). In multivariate analyses pneumonitis was associated with improved OS (hazard ratio [HR], 0.22; 95% confidence interval [CI] 0.12-0.44; P < 0.001), PFS (HR 0.37; 95% CI 0.21-0.66; P = 0.001) and CBR (odds ratio [OR] 4.11; 95% CI 1.42-11.95; P = 0.01). In cohort B, CT-verified pneumonitis (N = 29, 19.6%) was associated with improved OS (12.9 versus 6.0 months; P = 0.02), PFS (6.0 versus 2.8 months; P = 0.02) and CBR (79.3% versus 39.5%; P < 0.001). In multivariate analyses pneumonitis was associated with improved OS (HR 0.58; 95% CI 0.36-0.94; P = 0.03), PFS (HR 0.61; 95% CI 0.39-0.95; P = 0.03) and CBR (OR 5.65; 95% CI 2.10-15.18; P = 0.001). In a combined multivariate analysis (N = 233), with pneumonitis as a time-dependent covariate, CT-verified pneumonitis was associated with longer OS (HR, 0.67; 95% CI 0.46-0.97; P = 0.03). Furthermore, in a landmark analysis, pneumonitis was associated with longer OS (17.4 versus 7.8 months; P = 0.01). CONCLUSIONS: Everolimus-induced pneumonitis is associated with improved outcome in patients with mRCC and may serve as a biomarker of everolimus efficacy.

First-, second-, third-line therapy for mRCC: benchmarks for trial design from the IMDC.

BACKGROUND: Limited data exist on outcomes for metastatic renal cell carcinoma (mRCC) patients treated with multiple lines of therapy. Benchmarks for survival are required for patient counselling and clinical trial design. METHODS: Outcomes of mRCC patients from the International mRCC Database Consortium database treated with 1, 2, or 3+ lines of targeted therapy (TT) were compared by proportional hazards regression. Overall survival (OS) and progression-free survival (PFS) were calculated using different population inclusion criteria. RESULTS: In total, 2705 patients were treated with TT of which 57% received only first-line TT, 27% received two lines of TT, and 16% received 3+ lines of TT. Overall survival of patients who received 1, 2, or 3+ lines of TT were 14.9, 21.0, and 39.2 months, respectively, from first-line TT (P<0.0001). On multivariable analysis, 2 lines and 3+ lines of therapy were each associated with better OS (HR=0.738 and 0.626, P<0.0001). Survival outcomes for the subgroups were as follows: for all patients, OS 20.9 months and PFS 7.2 months; for those similar to eligible patients in the first-line ADAPT trial, OS 14.7 months and PFS 5.6 months; for those similar to patients in first-line TIVO-1 trial, OS 24.8 months and PFS 8.2 months; for those similar to patients in second-line INTORSECT trial, OS 13.0 months and PFS 3.9 months; and for those similar to patients in the third-line GOLD trial, OS 18.0 months and PFS 4.4 months. CONCLUSIONS: Patients who are able to receive more lines of TT live longer. Survival benchmarks provide context and perspective when interpreting and designing clinical trials.

Outcomes of patients with metastatic renal cell carcinoma that do not meet eligibility criteria for clinical trials.

BACKGROUND: Targeted therapies in metastatic renal cell carcinoma (mRCC) have been approved based on registration clinical trials that have strict eligibility criteria. The clinical outcomes of patients treated with targeted agents but are ineligible for trials are unknown. PATIENTS AND METHODS: mRCC patients treated with vascular endothelial growth factor-targeted therapy were retrospectively deemed ineligible for clinical trials (according to commonly used inclusion/exclusion criteria) if they had a Karnofsky performance status (KPS) <70%, nonclear-cell histology, brain metastases, hemoglobin ≤9 g/dl, creatinine >2× the upper limit of normal, corrected calcium ≥12 mg/dl, platelet count of <100 × 10(3)/uL, or neutrophil count <1500/mm(3). RESULTS: Overall, 768 of 2210 (35%) patients in the International Metastatic RCC Database Consortium (IMDC) were deemed ineligible for clinical trials by the above criteria. Between ineligible versus eligible patients, the response rate, median progression-free survival (PFS) and median overall survival of first-line targeted therapy were 22% versus 29% (P = 0.0005), 5.2 versus 8.6 months, and 12.5 versus 28.4 months (both P < 0.0001), respectively. Second-line PFS (if applicable) was 2.8 months in the trial ineligible versus 4.3 months in the trial eligible patients (P = 0.0039). When adjusted by the IMDC prognostic categories, the HR for death between trial ineligible and trial eligible patients was 1.55 (95% confidence interval 1.378-1.751, P < 0.0001). CONCLUSIONS: The number of patients that are ineligible for clinical trials is substantial and their outcomes are inferior. Specific trials addressing the unmet needs of protocol ineligible patients are warranted.

Tumour-associated CD66b+ neutrophil count is an independent prognostic factor for recurrence in localised cervical cancer.

BACKGROUND: The prognostic impact of tumour-promoting immune cells in cervical cancer is unclear. METHODS: Federation of Gynaecology and Obstetrics (FIGO) stage IB and IIA cervical cancer patients (N=101) were assessed for tumour-associated CD66b(+) neutrophils and CD163(+) macrophages by immunohistochemistry in whole tissue sections using stereology. Results were correlated with previous results on tumour-infiltrating CD3(+), CD4(+), and CD8(+) lymphocytes in the same cohort with recurrence-free survival (RFS) as end point. RESULTS: The highest densities of CD66b(+) neutrophils and CD163(+) macrophages were observed in the peritumoural compartment (median 53.1 cells mm(-2) and 1.3% area fraction, respectively). Above median peritumoural and stromal CD66b(+) neutrophils and peritumoural CD163(+) macrophages were significantly associated with short RFS. Multivariate analysis identified high peritumoural neutrophils (HR 2.27; 95% CI 1.09-4.75; P=0.03), low peritumoural CD8(+) lymphocytes (HR 3.67; 95% CI 1.63-8.25; P=0.002), and lymph node metastases (HR 2.70; 95% CI 1.26-5.76; P=0.01) as independent prognostic factors for short RFS, whereas CD163(+) macrophages were not significant. An index of combined intratumoral and peritumoral CD66b(+) neutrophils to CD8(+) lymphocytes had good discriminatory power for each quartile with 5-year RFS of 92%, 80%, 62%, and 44% (P=0.001). CONCLUSION: Tumour-associated neutrophil count is an independent prognostic factor for short RFS in localised cervical cancer. Combining CD66b and CD8 may further improve prognostic stratification. These findings require prospective validation.

Primary anti-vascular endothelial growth factor (VEGF)-refractory metastatic renal cell carcinoma: clinical characteristics, risk factors, and subsequent therapy.

BACKGROUND: A subset of patients treated with initial anti-vascular endothelial growth factor (VEGF) therapy exhibit progressive disease (PD) as the best response per RECIST criteria. METHODS: Data from patients with metastatic renal cell carcinoma (mRCC) treated with anti-VEGF therapy were collected through the International mRCC Database Consortium from 12 centers. RESULTS: One thousand and fifty-six assessable patients received initial VEGF inhibitors and 272 (26%) of these patients had PD as best response. Initial treatment included sunitinib (n = 203), sorafenib (n = 51), or bevacizumab (n = 18). Six percent of patients were at favorable risk, 55% at intermediate risk, and 39% at poor risk. On multivariable analysis, predictors of PD were Karnofsky performance status < 80% [odds ratio (OR) = 2.3, P < 0.0001], diagnosis to treatment < 1 year (OR = 2.1, P < 0.0001), neutrophilia (OR = 1.9, P = 0.0021), thrombocytosis (OR = 1.7, P = 0.0068), and anemia (OR = 1.6, P = 0.0058). Median progression-free survival (PFS) in patients with PD versus without PD was 2.4 versus 11 months (P < 0.0001) and overall survival (OS) was 6.8 versus 29 months (P < 0.0001), respectively. One hundred and eight (40%) VEGF-refractory patients proceeded to receive further systemic therapies. Response rate, PFS, and OS for subsequent therapy were 9%, 2.5 months, and 7.4 months, respectively, with no statistical differences between patients who received VEGF versus mammalian target of rapamycin (mTOR) inhibitors. CONCLUSIONS: Primary anti-VEGF-refractory mRCC patients have a dismal prognosis. Second-line anti-mTOR and anti-VEGF agents produce similar outcomes.

Hyponatremia as a prognostic and predictive factor in metastatic renal cell carcinoma.

BACKGROUND: Low serum sodium has recently been associated with poor survival in localised renal cell carcinoma (RCC). We now show the prognostic effect of serum sodium in patients with metastatic RCC (mRCC). METHODS: Cohort A comprised 120 consecutive patients with mRCC receiving subcutaneous, low-dose interleukin-2 and interferon-alpha. Hyponatremia was assessed in univariate and multivariate analyses. An independent cohort of another 120 patients with mRCC was used for validation (cohort B). RESULTS: In cohort A, estimated 5-year survival was 15% and median survival was 15.1 months. Serum sodium ranged between 126 and 144 mM. Twenty-four patients (20%) had serum sodium levels below normal range (<136 mM). In multivariate analysis, significant independent risk factors for short survival were low serum sodium (P=0.014), high neutrophils (P=0.018), lactate dehydrogenase >1.5 upper normal level (P=0.002), and number of metastatic sites (+3) (P=0.003). In cohort B, serum sodium ranged between 128 and 146 mM. Seventeen patients (14%) had sodium levels below normal range. In multivariate analysis, serum sodium was validated as an independent prognostic factor (P=0.001). A significant association between lack of response and hyponatremia was observed in both cohorts (P=0.003 and P=0.02, respectively). CONCLUSION: Low serum sodium is a new, validated, independent prognostic, and predictive factor in patients with mRCC.

Monocytes and neutrophils as 'bad guys' for the outcome of interleukin-2 with and without histamine in metastatic renal cell carcinoma--results from a randomised phase II trial.

Histamine (HDC) inhibits formation and release of phagocyte-derived reactive oxygen species, and thereby protects natural killer (NK) and T cells against oxidative damage. Thus, the addition of histamine may potentially improve the efficacy of interleukin-2 (IL-2). We have explored this potential mechanism clinically in two randomised phase II trials in metastatic renal cell carcinoma (mRCC). In parallel with the clinical trial in Denmark (n=63), we obtained serial blood samples and tumour biopsies searching for a potential histamine effect in situ. At baseline and on-treatment weeks 3 and 8, we monitored the 'good guys' (i.e. NK and T cells) and 'bad guys' (i.e. monocytes/macrophages and neutrophils) simultaneously in blood (n=59) and tumour tissue (n=44). Patients with high number of monocytes and neutrophils in peripheral blood had very poor survival, with apparently no benefit from either IL-2 alone or IL-2/HDC treatment. Blood monocytes (r=-0.36, P=0.01) and neutrophils (r=-0.46, P=0.001) were negatively correlated with cytotoxicity, whereas blood NK cells were positively correlated with cytotoxicity (r=0.39, P=0.002). Treatment with IL-2 alone resulted in a significantly higher number of circulating monocytes (P=0.037) and intratumoral macrophages (P=0.005) compared with baseline. In contrast, IL-2/HDC resulted in an unchanged number of circulating monocytes and intratumoral macrophages, and in addition, a significantly increased number of intratumoral CD56(+) NK cells (P=0.008) and CD8(+) T cells (P=0.019) compared with baseline. The study provides evidence that circulating monocytes and neutrophils are powerful negative prognostic factors for IL-2-based immunotherapy and establishes a biological rationale for the potential use of histamine in conjunction with IL-2 in mRCC.

Two randomised phase II trials of subcutaneous interleukin-2 and histamine dihydrochloride in patients with metastatic renal cell carcinoma.

Histamine inhibits formation and release of phagocyte-derived reactive oxygen species, and thereby protects natural killer and T cells against oxidative damage. Thus, the addition of histamine may potentially improve the efficacy of interleukin-2 (IL-2). Two randomised phase II trials of IL-2 with or without histamine dihydrochloride (HDC) in patients with metastatic renal cell carcinoma (mRCC) were run in parallel. A total of 41 patients were included in Manchester, UK and 63 in Aarhus, Denmark. The self-administered, outpatient regimen included IL-2 as a fixed dose, 18 MIU s.c. once daily, 5 days per week for 3 weeks followed by 2 weeks rest. Histamine dihydrochloride was added twice daily, 1.0 mg s.c., concomitantly with IL-2. A maximum of four cycles were given. The Danish study showed a statistically significant 1-year survival benefit (76 vs 47%, P = 0.03), a trend towards benefit in both median survival (18.3 vs 11.4 months, P = 0.07), time to PD (4.5 vs 2.2 months, P = 0.13) and clinical benefit (CR + PR + SD) (58 vs 37%, P = 0.10) in favour of IL-2/HDC, whereas the UK study was negative for all end points. Only three patients had grade 4 toxicity; however, two were fatal. A randomised phase III trial is warranted to clarify the potential role of adding histamine to IL-2 in mRCC.

In vivo assessment of the antiproliferative properties of interferon-alpha during immunotherapy: Ki-67 (MIB-1) in patients with metastatic renal cell carcinoma.

The aim of the present study was to investigate the in vivo antiproliferative effect of interferon alpha (IFN-alpha) in patients with metastatic renal cell carcinoma (mRCC). Core needle biopsies of metastatic and/or the primary kidney cancer were obtained before interleukin-2 (IL-2)- and IFN-alpha-based immunotherapy in 34 patients and repeated after 5 weeks in 25 patients. Tumour proliferation was assessed by use of the anti-Ki-67 antibody MIB-1 and evaluated in multiple, random systematic sampled fields of vision. Ki-67 labelling index (LI) at baseline was median 13.6% (range 1.2-85.0) and median 10.6% (range 1.3-48.6%) at week 5 with a median overall decline of 15.2% (range -95 to +258%) from baseline to week 5. There was no difference between responding and nonresponding patients. Ki-67 LI at week 5 was significantly correlated to survival. Thus, median survival of patients with Ki-67 LI 10.6% (P=0.016). Baseline or change in Ki-67 LI did not correlate to survival. These data suggest that IFN-alpha in vivo has only modest effect on tumour proliferation in patients with mRCC. Tumour Ki-67 (MIB-1) reactivity after 1 month of immunotherapy appears to be a significant predictor of patient survival.

Intratumoural and peripheral blood lymphocyte subsets in patients with metastatic renal cell carcinoma undergoing interleukin-2 based immunotherapy: association to objective response and survival.

The aim of the present study was to analyse lymphocyte subsets in consecutive peripheral blood samples and consecutive tumour tissue core needle biopsies performed before and during interleukin-2 based immunotherapy, and to correlate the findings with objective response and survival. Twenty-six patients with metastatic renal cell carcinoma were treated with low dose s.c. interleukin-2, interferon-alpha and histamine. A total of 250 blood samples and 62 core needle biopsies from 23 and 19 of these patients, respectively, were analysed. After 2 weeks of treatment, a significant positive correlation between absolute number of peripheral blood lymphocytes (P=0.028), CD3 (P=0.017), CD57 (P=0.041) and objective response was demonstrated. There was no correlation between any peripheral blood leukocyte subsets and survival. Cytotoxicity of peripheral blood mononuclear cells was not correlated to objective response or survival. Within the tumour tissue at baseline, a significant positive correlation between CD4 (P=0.027), CD8 (P=0.028), CD57 (P=0.007) and objective response was demonstrated. After one month of immunotherapy, a significant positive correlation between intratumoral CD3 (P=0.026), CD8 (P=0.015), CD57 (P=0.009) and objective response was demonstrated. A significant positive correlation between intratumoral baseline CD4 (P=0.047), baseline CD57 (P=0.035), CD3 at one month (P=0.049) and survival was demonstrated. These data provide novel in vivo evidence of the possible contribution of lymphocyte subsets in the tumour reduction in responding patients during interleukin-2 based immunotherapy. Confirmation of the results requires further studies including a larger number of patients.

Outpatient treatment with subcutaneous histamine dihydrochloride in combination with interleukin-2 and interferon-alpha in patients with metastatic renal cell carcinoma: results of an open single-armed multicentre phase II study.

OBJECTIVES: Histamine inhibits formation and release of monocyte/macrophage-derived reactive oxygen metabolites and thereby protects natural killer (NK) and T cells against oxidative inhibition. Efficacy and safety of histamine, when given in combination with interleukin-2 (IL-2) and interferon-alpha (IFN-alpha), were evaluated in patients with metastatic renal cell carcinoma (mRCC). PATIENTS AND METHODS: Forty-eight mRCC patients were included. The self-administered, outpatient regimen included IFN-alpha, 3 MIU s.c., once daily for 1 week, followed by up to nine 4 week cycles of IFN-alpha, 3 MIU s.c., days 1-7, weeks 1-4; interleukin-2, 2.4 MIU/m2 s.c., b.i.d., days 1-5, weeks 1 and 2; and histamine dihydrochloride, 1 mg s.c., b.i.d. days 1-5, weeks 1-4. RESULTS: Forty-six patients were eligible. Forty-two patients were evaluable for response with four partial responses (9% of eligible patients, 10% of evaluable patients). Fifteen patients (36%) had stable disease. After subsequent surgery of residual tumours, three patients (7%) had no evidence of disease at 14+, 21+ and 21+ months. Median survival time for all patients was 16.3 months. One grade 4 toxicity (thrombocytopenia) was observed. Most frequent grade 3 toxicities were fatigue/malaise (26%), dyspnoe (11%), nausea (9%) and stomatitis (9%). Four patients discontinued due to treatment-related toxicity. There were no treatment-related deaths. CONCLUSIONS: The present combination of histamine with IL-2 and IFN-alpha. as self-administered outpatient therapy is a safe and well-tolerated regimen. However, histamine does not appear to add efficacy with respect to response in this low-dose schedule of IL-2 and IFN-alpha. Whether histamine might improve efficacy with higher doses of IL-2 and IFN-alpha requires further investigation.

Expression and function of LFA-1 on A-NK and T-LAK cells: role in tumor target killing and migration into tumor tissue.

To study the role of the adhesion molecule lymphocyte function-associated antigen 1 (LFA-1) in lymphokine-activated natural killer (A-NK) and mitogen-stimulated lymphokine-activated T killer (T-LAK) cell function, we evaluated the correlation between LFA-1 expression, as well as conjugate formation and cytotoxicity. Furthermore, the role of LFA-1 in the extravascular phase of migration of A-NK and T-LAK cells into B16 tumor tissue in vivo was studied. We demonstrate an 8-fold increased LFA-1 expression on 4-day-old A-NK and T-LAK cells compared to unstimulated spleen cells. Moreover, we demonstrate that while LFA-1 expression on T-LAK cells was strictly correlated to conjugate formation and cytotoxic capacity, A-NK cells showed a less clear correlation between LFA-1 expression and these functions. Interestingly, anti-CD11a alone did not inhibit cytotoxicity, anti-CD18 alone did only inhibit cytotoxicity moderately (25%) whereas anti-CD11a and anti-CD18 in combination almost abrogated cytotoxicity against tumor targets P815 and YAC-1. Finally we demonstrate that pre-incubation of T-LAK cells with anti-bodies to CD11a and CD18 in combination inhibited their migration into the B16 tumors by more than 50-60%. In contrast, this pretreatment did not inhibit A-NK cell migration. This difference could not be explained by differences between A-NK and T-LAK cells with respect to LFA-1 expression, turnover of antibody-receptor complexes or complement-mediated lysis induced by the anti-LFA-1 antibodies. We conclude that T-LAK cell binding to and lysis of tumor target cells and migration into the intercellular space of tumors depend strongly on the expression of LFA-1. In contrast, LFA-1 expression of A-NK cells showed a less clear correlation to these functions.