Humoral cytotoxicity in melanoma patients and its correlation with the extent and course of the disease

Hla Antigens in Malignant Melanoma Patients

One hundred and forty melanoma patients, divided in 2 groups, i.e., patients with clinical evidence of melanoma and patients with no clinical evidence of melanoma, were typed for HLA-A, -B and -C antigens and compared with 340 to 905 (according to each HLA antigen examined) healthy adult blood donors. Overall, a highly significant increase in HLA-B40 antigen (p = 5.6 × 10−7) and a decrease in HLA-BW35 (p = 1.6 × 10−4) was observed. No relevant difference was found between the 2 groups. Moreover, an unexpected excess of HLA blanks was observed at both A and B loci in the first group (p = 1.3 × 10−2 and p = 3.3 × 10−6, respectively) and only at the B locus in the second (p = 1.2 × 10−2), when the patients were compared to 288 healthy individuals HLA typed at the same time and with the same HLA antisera as the patients. The increase in HLA blanks in melanoma patients deserves further investigation to ascertain whether it may be due to the tumor not yet surgically removed or may be referred to technical pitfalls.

Malignant melanoma of unknown primary site. To make the long story short. A systematic review of the literature

INTRODUCTION

Although more than 90% of melanomas have a cutaneous origin, occasionally it is discovered as a secondary deposit without evident primary site. The aim of this study was to systematically review published literature and analyse data on incidence, presentation, therapeutic interventions, survival and prognostic factors.

METHODS

We searched MEDLINE, (search terms Melanom*, unknown origin, unknown primary, indolent, occult) and the abstracts from major congresses of the last 4 years and perused the references of the retrieved relevant articles.

RESULTS

4348 patients with MUP were reported along with 132,643 patients with Melanoma of Known Primary (MKP). The incidence of MUP was 3.2%. The male to female ratio was 2:1 while the age peak was in the 4th and 5th decades. MUP patients harbouring nodal disease had a median overall survival ranging between 24 and 127 months, 5-year survival rate between 28.6% and 75.6% and 10-year survival rate between 18.8% and 62.9%. MUP patients with visceral disease had median survival times between 3 and 16 months, and 5-year survival rates between 5.9% and 18%. Presence of tumour regression in metastatic sites and low nodal burden were associated with favourable outcome. Potentially curative surgical treatment offered survival advantage in comparison to patients with residual metastatic foci. MUP patients who received adjuvant chemotherapy or radiotherapy paradoxically seemed to fare worse compared to patients observed.

CONCLUSIONS

This is the first review to bring together the information of 89 years and to analyze all the potential information accumulated. Although a well know entity no consensus is reached in order to describe MUP presentation, management or prognosis.

Improved survival after lymphadenectomy for nodal metastasis from an unknown primary melanoma

PURPOSE

No primary lesion is identified in 10% to 20% of patients presenting with palpable evidence of regional metastatic melanoma. Because the prognostic significance of unknown primary melanoma (MUP) is unclear, we compared clinical outcomes of patients with MUP and known primary melanoma (MKP) with regional nodal metastases.

PATIENTS AND METHODS

We reviewed our 13,000-patient prospective melanoma database (1971 through 2005) to identify patients managed with regional lymphadenectomy for palpable nodal metastases from MUP or MKP. Multivariate analysis identified prognostic factors significant for survival. MUP and MKP were then matched by significant covariates. Overall survival (OS) was estimated by Kaplan-Meier method and compared by log-rank analysis.

RESULTS

Multivariate analysis of data from 1,571 study patients identified four significant covariates associated with worse prognosis: age >or= 60 years (hazard ratio [HR] = 1.294; P = .0017), male sex (HR = 1.335; P = .0004), nodal tumor burden >or= one (HR = 1.256; P < .0001), and known primary (HR = 1.507; 95% CI, 1.220 to 1.862; P = .0001). Five-year OS was significantly higher for 262 patients with MUP than for 1,309 patients with MKP (55% +/- 6% v 44% +/- 3%; P = .0021). Computerized matching of MUP and MKP by four significant covariates (age, sex, nodal tumor burden, and decade of diagnosis) yielded 221 matched pairs. Median and 5-year OS rates were 165 months and 58% +/- 7%, respectively, for MUP as compared with 34 months and 40% +/- 7%, respectively, for MKP (P = .0006).

CONCLUSION

Lymphadenectomy is effective for nodal metastasis from MUP. The significantly better postoperative survival for MUP versus MKP suggests a strong endogenous immune response against the primary melanoma. Immunologic studies to identify cell-mediated and antibody components of this response may lead to new approaches for determining melanoma prognosis and treatment.

Peripheral Blood CD4+ T-Cell Response Before Postoperative Active Immunotherapy Correlates with Clinical Outcome in Metastatic Melanoma

BACKGROUND

Canvaxin polyvalent specific active immunotherapeutic (CancerVax Corp., Carlsbad, CA) is a minimally toxic adjuvant after resection of regional metastatic melanoma. Because Canvaxin immunotherapeutic requires induction of an immune response, we hypothesized that survival would be directly correlated with cellular immune responses to Canvaxin cells prior to immunization.

METHODS

We randomly selected 54 patients from a study of Canvaxin therapy after complete resection of American Joint Committee on Cancer (AJCC) stage III melanoma. Peripheral blood lymphocytes (PBLs) collected before immunotherapy were co-cultured with Canvaxin cells; cellular response was determined by flow cytometric measurement of the production of intracellular interleukin 4 (IL4) or interferon gamma (IFNgamma) by CD4(+) T-cells. Results were calculated as percent positive for double staining of CD4(+) plus IL4(+) or CD4(+) plus IFNgamma(+).

RESULTS

The mean (+/- SD) increase in cytokine-producing CD4(+) T-cells after Canvaxin stimulation was 4.8 +/- 2.3% for an IFN response and 5.1 +/- 2.0% for an IL4 response. Both increases were significantly correlated with overall survival by univariate analysis (P = .0471 for IFNgamma and 0.002 for IL4). There was no significant correlation between unstimulated IFNgamma/IL4 responses and overall survival. Multivariate analysis showed that a CD4(+) T-cell IL4 response before Canvaxin therapy was a significant independent prognostic variable.

CONCLUSIONS

In vitro cellular immune response to Canvaxin cells directly correlates with survival after subsequent initiation of immunotherapy for AJCC stage III melanoma. This finding will be evaluated in a multicenter phase III trial of Canvaxin plus bacille Calmette-Guerin (BCG) versus placebo plus BCG after resection of stage III melanoma.

Prolonged survival after complete resection of disseminated melanoma and active immunotherapy with a therapeutic cancer vaccine

PURPOSE

The curative effect of surgery in certain patients with metastatic melanoma suggests the presence of endogenous antitumor responses. Because melanoma is immunogenic, we investigated whether a therapeutic cancer vaccine called Canvaxin (CancerVax Corporation, Carlsbad, CA) could enhance antitumor immune responses and thereby prolong survival.

PATIENTS AND METHODS

Of 263 patients who underwent complete resection of American Joint Committee on Cancer stage IV melanoma, 150 received postoperative adjuvant vaccine therapy and 113 did not. The overall survival (OS) for the two groups was compared by Cox regression. Further survival analysis was performed by matched-pair analysis according to three prognostic variables: sex, metastatic site, and number of tumor-involved organ sites.

RESULTS

Five-year OS rates were 39% for vaccine and 19% for nonvaccine patients. On multivariate analysis, vaccine therapy was the most significant prognostic variable in this cohort (P =.0001). Analysis of 107 matched pairs of vaccine and nonvaccine patients revealed a significant OS advantage for vaccine therapy (P =.0009): 5-year OS was 39% for vaccine patients versus 20% for nonvaccine patients. There was a significant delayed-type hypersensitivity (DTH) response to adjuvant vaccine therapy (P =.0001), and OS was significantly correlated with DTH to vaccine (P =.0001) but not with DTH to purified protein derivative (PPD), a control antigen.

CONCLUSION

Prolonged survival was observed in patients who received postoperative active immunotherapy with Canvaxin therapeutic cancer vaccine. The correlation of survival with vaccine-DTH responses but not PPD-DTH indicates a treatment-specific effect. These findings suggest that adjuvant active specific immunotherapy should be considered after cytoreductive surgery for advanced melanoma.

Tumour cell-based vaccines for the treatment of melanoma

Melanoma is generally resistant to chemotherapy and radiation therapy. Its unique immunological properties lend support to developing innovative new therapies via manipulation of the patient's own immune system. The use of whole-cell-based tumour vaccines, including autologous, whole-cell allogeneic and cytokine gene-modified vaccines, as well as tumour lysate vaccines, for active specific immunotherapy of melanoma, is discussed in detail with regard to rationale and available clinical data. Although phase II data on the use of melanoma vaccine in the adjuvant setting show promise, there is no randomised phase III trial demonstrating the efficacy of active specific immunotherapy for melanoma. The coming years will bring the results of several pivotal multicentre phase III trials testing the clinical utility of active specific immunotherapy in the management of melanoma.

Does endogenous immune response determine the outcome of surgical therapy for metastatic melanoma?

BACKGROUND

Although the presence of tumor cells in the blood of patients with metastatic melanoma suggests widely disseminated disease, many of these patients enjoy prolonged survival or cure after surgical resection. Our previous study of adjuvant vaccine therapy after complete resection of metastatic melanoma revealed a strong correlation between postoperative survival and elevated antibody titers to a 90-kDa tumor-associated antigen (TA90) expressed by melanoma cells of the vaccine. We hypothesized a similar correlation between postoperative survival and endogenous anti-TA90 antibody titers induced by the patient's melanoma in the absence of postoperative adjuvant immunotherapy.

METHODS

From 1970 to 1996, 64 patients underwent complete resection of distant melanoma metastases and did not receive postoperative adjuvant immunotherapy. Serum collected within 4 months after surgery was tested in a coded and blinded fashion for anti-TA90 IgG and IgM by enzyme-linked immunosorbent assay, and for total IgG and IgM (controls) by radial immunodiffusion.

RESULTS

Median follow-up for the study population was 19 months (range, 3-147 months). There was no significant correlation between anti-TA90 IgG titer and total IgG level (P = .4785), or between anti-TA90 IgM and total IgM (P = .0989). Univariate analysis showed that postoperative anti-TA90 IgM titer as a continuous variable was significantly associated with overall survival (OS); i.e., the higher the anti-TA90 IgM titer, the longer the OS. Using an established cutoff titer of 800, median OS was 42 months for patients with high anti-TA90 IgM titers (n = 28) vs. 9 months for patients with low titers (n = 36) (P = .0001). There was no significant correlation between total IgG/IgM and survival (P = .4107 and .4044, respectively). Multivariate analysis identified anti-TA90 IgM as the most significant independent variable influencing OS after complete resection of distant melanoma metastases (P = .0001).

CONCLUSIONS

We conclude that the endogenous immune response to metastatic melanoma determines the outcome after surgical therapy. Enhancement of this specific immune response may prolong the survival of patients with distant melanoma metastases.

Enhancement of complement-dependent cytotoxicity by polyvalent melanoma cell vaccine (CancerVax): correlation with survival

BACKGROUND

Case control studies have demonstrated that administration of CancerVax, a polyvalent melanoma cell vaccine (PMCV), after complete resection of melanoma metastases produces a significant improvement in disease-free survival (DFS). Because PMCV has no direct cytotoxic effect on melanoma cells, the authors hypothesized that it prolongs survival by enhancing antibody-mediated antimelanoma cytotoxicity.

METHODS

One hundred melanoma patients participating in a trial of PMCV adjuvant therapy following complete resection of regional node metastases were randomly selected for study. Serum samples obtained immediately before (T0) and 4, 8, 12, and 16 weeks after initiation of PMCV adjuvant therapy were adsorbed with L-14 lymphoblastoid cells and then tested for in vitro complement-dependent cytotoxicity (CDC) against M-14 cells, a melanoma cell line not used in PMCV. CDC was expressed as percentage of total cells (n = 10,000) killed. Survival curves were estimated by the Kaplan-Meier method. Statistical analysis was performed by the signed rank sum test, Spearman test, log-rank test, and Cox proportional hazard regression.

RESULTS

Median CDC at T0 was 4.5% (range, 0% to 40%). Within 16 weeks after initiation of PMCV therapy, CDC had increased in 82 (82%) patients. The median increase of 7.5% (range, -9% to 39%) represented a highly significant change (signed rank sum test; P = .0001). At a median follow-up of 29 months (range, 6 to 92 months), the maximum increase in CDC (deltaCDC) as a continuous variable was significantly correlated with DFS (P = .0001). Median survival and 5-year DFS were more than 54 months and less than 54%, respectively, for patients with deltaCDC > or =10% (n = 44) but only 7 months and 14%, respectively, for those with deltaCDC <10% (n = 56; P = .0001). Multivariate analysis confirmed deltaCDC as the most significant independent variable associated with DFS following initiation of PMCV therapy (P = .0001).

CONCLUSION

PMCV therapy greatly enhances serum CDC against melanoma cells. This enhancement is directly correlated with DFS following initiation of vaccine therapy.

Absence of melanoma specificity in the reactivity of melanoma patients' sera with cultured allogeneic melanoma cell lines

While patients with melanoma are known to produce antibodies against melanoma cells, the tumor specificity of these reactions has not been well documented. Using the sensitive mixed hemadsorption assay we have identified antibody against one or more of nine different cultured melanoma cell lines in only nine of 48 patients with melanoma. Reactivity against melanoma cell lines was seen only in females, 9/27 versus 0/21 males. The strongest melanoma reactivity was seen in sera which also contained lymphocytotoxic antibody. The reactivity was not melanoma specific because it could be removed by absorption either with pooled platelets, nonmelanoma tumor cells or in two cases, by both. We conclude that the occurrence of specific antimelanoma antibodies against common or shared surface melanoma associated antigens is an uncommon event in melanoma patients not receiving specific active immunotherapy. The clinical significance of the observed reactivity and whether it is directed against cancer associated determinants, fetal antigens, or normal tissue or histocompatibility antigens requires further study.

Receptor sites for complement and for immune complexes on human nonhemopoietic tumor cells

Tumor cells in primary cultures derived from 11 untreated nonhemopoietic cancer patients were reacted with specifically coated sheep erythrocytes. Rosette formation between tumor and indicator cells was assessed, Eight of the primary cultures reacted positively with both IgG-coated (EAIgG) and with IgM-human complement coated (EAIgMC or EAIgMC 4,3) sheep erythrocytes. EAIgG rosette formation in positive cultures ranged from 25 to 85%, and for EAIgMC/EAIgMC 4,3 reactivity ranged between 22--95%. Rosette formation with E (uncoated) and EAIgM was negligible. These findings suggest that human nonhemopoietic tumor cells may carry on their surface receptor sites for an IgG component of immune complexes and for human complement. These receptor sites may be important in the host-tumor relationship.

Antibody Binding to Membrane of Cultured Melanoma Cells by Sera of Melanoma Patients

One hundred and nine sera from 75 patients with malignant melanoma and 69 sera from as many healthy donors were assayed by isotopic antiglobulin technique (IAT) on 2 melanoma cell lines. The same picture of reactivity was observed with patients’ and healthy donors’ sera, and in both groups 35% of the cases were high responders on 1 line and 21% on the other one. The specificity of the reactions was analyzed by absorption experiments using 12 melanoma sera selected for their high binding activity. Pools of human erythrocytes or leukocytes did not remove, except in 1 case respectively, the activity of the sera, suggesting that it was not directed against alloantigens. Quantitative absorption experiments were done with the 2 melanoma lines and with 1 colon carcinoma line. The results, evaluated on the basis of absorption capacity per cell, indicate that the 2 melanoma lines had a similar amount of shared antigens, whereas the colon line was also effective in absorbing out the serum activity, but less frequently and less efficiently. Further experiments performed to analyze the influence of culturing the target cells in presence of fetal bovine serum (FBS), showed that the activity of sera was removed, at various degrees for different sera, by absorption with free FBS, with FBS coupled to Sepharose 4B, and with normal leukocytes cultured overnight with 10% FBS. The same positive melanoma sera became negative when assayed on the same melanoma line cultured in γ-globulin-depleted human AB serum. In conclusion, in our experimental conditions, the activity of melanoma sera seems mostly directed against components of FBS absorbed on cell membrane during culturing.

Complement - dependent Serum Cytotoxicity of Cancer Patients Studied by 51Cr Release Assay on Human Cancer Lines

The conditions for a 51Cr release assay on cell lines derived from human solid tumors were determined by using a rabbit antihuman antiserum with human AB serum as source of complement. By this assay 38 sera collected before and after surgery from 19 breast cancer patients and 28 sera from 12 melanoma patients and 16 healthy donors were tested on 3 lines derived from breast cancer tissue and 1 line derived from normal breast tissue. Ten of the breast cancer patients had lymph node metastases and 9 did not. Positive reactions were obtained from 4 breast cancer patients, all with lymph node metastases, and from 1 healthy donor. In a second experiment, 58 coded sera belonging to 4 different groups of cancer and non-cancer individuals were assayed on a colonic cancer line (HT-29), and 33 and 20 of them were also tested on a melanoma line (MeWo) and on a breast cancer line (MaCa 13), respectively. Positive responses were few, and were more frequently observed among transfused than non-transfused patients.