Malignant melanoma in black Americans. A trend toward improved survival

A search of patients seen at the Duke University Melanoma Clinic (Durham, NC) identified 79 black patients. Five- and 10-year survival was 35% and 26%, respectively. Patients presenting in the recent decade had less advanced disease, resulting in an improved 5-year survival of 49%. Five-year survival for white patients was 74%. Black patients had more negative prognostic indicators when compared with white patients. In a multivariate analysis, however, race was not a prognostic indicator, suggesting melanoma is not inherently more aggressive in black patients. The trend during the past decade has been for black patients to present with less advanced disease, with improved survival. This may be related to better appreciation of the disease by patients and physicians alike. Continued emphasis on education and early diagnosis may result in further improvement for black patients with melanoma.

Cell binding and tumor inhibiting functions of a new antihuman melanoma murine monoclonal antibody

Murine, antihuman melanoma cell monoclonal antibody (mAb) 16.C8 was generated by fusing the murine myeloma cell line P3X63/Ag8.653 with splenocytes from a nude mouse bearing a human melanoma xenograft, after reconstitution with splenocytes from syngeneic immunocompetent BALB/c mice. The antibody reacted strongly with fresh human melanoma cells and exhibited preferential reactivity with established human melanoma and neuroectodermal tumor cell lines. Electrophoresis and Western blotting experiments indicated that 16.C8 is directed against a sialoglycoprotein antigen with a molecular weight of 110-120 kDa. mAb 16.C8 mediated lysis of melanoma cells in vitro in antibody-dependent cellular cytotoxicity assays using human mononuclear effector cells isolated from normal volunteers or malignant melanoma patients. In addition, the administration of mAb 16.C8 to nude mice bearing established human melanoma lung and liver metastases resulted in significant inhibition of tumor growth as shown by gross and histologic examination. In contrast, animals treated with Hanks' balanced salt solution or nonspecific immunoglobulin exhibited a large tumor burden. These results suggest that mAb 16.C8 may be of value in treatment of metastatic melanoma in humans.

Experimental trials of immunotherapy for malignant melanoma

Conventional treatment for metastatic melanoma consists of surgical resection, chemotherapy, and radiation therapy. New approaches toward treatment of this disease include the development of passive and active immunotherapeutic regimens. Malignant melanoma is particularly amendable to immunotherapy since the tumor is relatively immunogenic, expressing unique cell surface protein and lipid antigens. Clinical trials investigating the benefit of active specific immunotherapy documented increased survival of invasive Stage 1 and metastatic Stage 2 melanoma patients following immunization with tumor cell vaccines and BCG. Additional trials showed that the development of specific antibodies after immunization of Stage 2 patients with a viral oncolysate was correlated with an increased survival compared to matched controls given only BCG. Passive immunotherapy approaches using either lymphokine-activated killer (LAK) cells or tumor-infiltrating lymphocytes (TIL) administered with interleukin 2 have also resulted in regression of disease with complete or partial remissions occurring in 25% of the patients. Additional studies have focused on the generation of specific cytotoxic T lymphocytes by stimulation with autologous tumor in vivo. Future trials will evaluate the therapeutic efficacy of these specific cytologic T lymphocytes relative to LAK and TIL.

Treatment of human melanoma hepatic metastases in nude mice with human cytotoxic T lymphocytes

We investigated the effects of human melanoma-specific cytotoxic T lymphocytes in treating experimental human melanoma hepatic metastases in a nude mouse model of adoptive immunotherapy. Hepatic metastases were generated by intrasplenic injection of 1.5 x 10(6) human melanoma cells. Three days after injection, animals received salt solution and interleukin 2 or interleukin 2 and cytotoxic T lymphocytes. Twenty-four of 25 control animals had developed multiple tumor nodules in the liver; 11 of 13 animals receiving only interleukin 2 also had significant tumor burdens. In striking contrast, 17 of 18 animals receiving cytotoxic T lymphocytes and interleukin 2 had no gross or histologic evidence of tumors. The remaining animal had a 2-mm nodule. Human tumor-specific cytotoxic T lymphocytes are effective in vivo in a model of adoptive immunotherapy and may prove useful in adoptive immunotherapy of humans with metastatic melanoma.

MHC-restricted recognition of autologous melanoma by tumor-specific cytotoxic T cells. Evidence for restriction by a dominant HLA-A allele

Autologous melanoma-specific CTL recognize a common tumor-associated Ag (TAA) in the context of HLA class I antigens. We have demonstrated that HLA-A2 can be a restricting Ag and, in T cell lines homozygous for HLA-A2, that CTL can be generated by stimulation with HLA-A2 allogeneic melanomas. In the current study, we have investigated T cell lines from patients who are heterozygous at HLA-A region locus, to determine the relative importance of each A-region allele in this MHC-restricted recognition of tumor. We have shown that HLA-A1 can be a restricting Ag, and that allogeneic melanomas expressing HLA-A1 can substitute for the autologous tumor in the generation of HLA-A1-restricted CTL. However, when T cell lines express both HLA-A1 and HLA-A2, the HLA-A2 allele governed restriction of the melanoma TAA. Three autologous-stimulated HLA-A1, A2 CTL lines all demonstrated restriction by the HLA-A2 allele, when examined in cytotoxicity assays, cold-competition assays, and proliferation assays. There was no evidence of restriction by the second HLA-allele, HLA-A1. Although the autologous-stimulated CTL use a single A-region allele for tumor recognition, the autologous HLA-A1, A2 tumors are lysed by both HLA-A1-restricted and HLA-A2-restricted CTL. The dominance of restricting alleles was further demonstrated when HLA-matched allogeneic melanomas were used as the stimulating tumor to generate tumor-specific CTL. Stimulation of the heterozygous (HLA-A1, A2) lymphocytes with HLA-A2-matched allogeneic melanomas resulted in CTL specific for the autologous tumor, and restricted by the HLA-A2 Ag. However, stimulation with an HLA-A1-matched allogeneic melanoma failed to induce tumor-specific CTL restricted by the HLA-A1 Ag. The data suggest there is a dominance of HLA-A region Ag at the level of the T cell, such that only one is restricting in the recognition of the autologous melanoma. At the level of the tumor, however, the TAA is expressed in the context of both HLA-A region alleles. We can generate specific CTL from lymph node cells or PBL and HLA-A region matched allogeneic melanomas; however, because most patients are heterozygous at the HLA-A region locus, an understanding of the dominant restricting alleles must be obtained so that an appropriately matched allogeneic melanoma can be selected.

MHC-restricted recognition of autologous melanoma by tumor-specific cytotoxic T cells. Evidence for restriction by a dominant HLA-A allele

Autologous melanoma-specific CTL recognize a common tumor-associated Ag (TAA) in the context of HLA class I antigens. We have demonstrated that HLA-A2 can be a restricting Ag and, in T cell lines homozygous for HLA-A2, that CTL can be generated by stimulation with HLA-A2 allogeneic melanomas. In the current study, we have investigated T cell lines from patients who are heterozygous at HLA-A region locus, to determine the relative importance of each A-region allele in this MHC-restricted recognition of tumor. We have shown that HLA-A1 can be a restricting Ag, and that allogeneic melanomas expressing HLA-A1 can substitute for the autologous tumor in the generation of HLA-A1-restricted CTL. However, when T cell lines express both HLA-A1 and HLA-A2, the HLA-A2 allele governed restriction of the melanoma TAA. Three autologous-stimulated HLA-A1, A2 CTL lines all demonstrated restriction by the HLA-A2 allele, when examined in cytotoxicity assays, cold-competition assays, and proliferation assays. There was no evidence of restriction by the second HLA-allele, HLA-A1. Although the autologous-stimulated CTL use a single A-region allele for tumor recognition, the autologous HLA-A1, A2 tumors are lysed by both HLA-A1-restricted and HLA-A2-restricted CTL. The dominance of restricting alleles was further demonstrated when HLA-matched allogeneic melanomas were used as the stimulating tumor to generate tumor-specific CTL. Stimulation of the heterozygous (HLA-A1, A2) lymphocytes with HLA-A2-matched allogeneic melanomas resulted in CTL specific for the autologous tumor, and restricted by the HLA-A2 Ag. However, stimulation with an HLA-A1-matched allogeneic melanoma failed to induce tumor-specific CTL restricted by the HLA-A1 Ag. The data suggest there is a dominance of HLA-A region Ag at the level of the T cell, such that only one is restricting in the recognition of the autologous melanoma. At the level of the tumor, however, the TAA is expressed in the context of both HLA-A region alleles. We can generate specific CTL from lymph node cells or PBL and HLA-A region matched allogeneic melanomas; however, because most patients are heterozygous at the HLA-A region locus, an understanding of the dominant restricting alleles must be obtained so that an appropriately matched allogeneic melanoma can be selected.

The role of resection in the management of melanoma metastatic to the adrenal gland

Melanoma metastatic to the adrenal gland diagnosed before death was exceedingly rare before the development of computed tomographic (CT) scanning. The records of 28 patients with melanoma metastatic to the adrenal gland seen since 1975 were reviewed. Eighteen patients were men and 10 were women. Twenty-three patients had unilateral disease. Four patients were diagnosed only at autopsy, leaving 24 for analysis of treatment and survival. Twenty-one patients had received specific active immunotherapy, four had received chemotherapy (dacarbazine, lomustin, bleomycin, and vincristine), and three had received both before the diagnosis of their adrenal disease. Adrenal metastases were diagnosed by CT scanning in 14 patients with symptoms, 10 (91%) of whom had pain. Ten patients were diagnosed by CT before entry into a chemotherapy protocol. Of eight patients who underwent resection of all known disease, five underwent unilateral adrenalectomy, two underwent unilateral adrenalectomy and bowel resection, and one underwent bilateral adrenalectomy. Two patients underwent partial resection of large unilateral tumors. Fourteen patients with adrenal metastases and disease elsewhere were initiated or continued with chemotherapy or were treated symptomatically. Mean survival in the group that underwent resection for cure was 59 months (3 to 112 months), whereas survival in the group with unresectable tumors was 15 months (1.5 to 132 months). Four of eight patients who underwent resection for cure lived more than 5 years after detection of adrenal metastasis, whereas in only one of 14 patients with unresectable tumors was the same true. Patients with metastatic melanoma localized to one or both adrenal glands may benefit from early detection and surgical intervention.

The role of elective lymph node dissection in the management of patients with thick cutaneous melanoma

A retrospective search of patients seen at the Duke Melanoma Clinic from 1970 to 1986 identified 308 clinically Stage I patients, with 4.0 to 10.0 mm cutaneous melanomas. Five-year and ten-year survival was 56% and 43%, respectively. Elective lymph node dissection (ELND) was done in 116 patients (37.7%); there was no difference in disease-free interval (DFI) or survival between these patients versus patients treated with wide excision only (P = 0.9). Thirty-two patients (27.6%) had pathologically positive nodes on ELND. These patients had a shorter DFI (P = 0.05) and survival (P = 0.03) compared with patients with negative node dissections. When further divided by Breslow's thickness, this difference persisted in patients with 4.0 to 6.0 mm lesions (P = 0.01). However, for thicker lesions (greater than 6.0 mm), there was no difference in survival between the node-negative and node-positive groups (P = 0.9). The mean follow-up was 7.1 years. Elective lymph node dissection was not done in 192 patients; 78 of these recurred first in the regional nodes. These 78 patients were compared with the 32 patients who had pathologically positive nodes by ELND to see if patient survival was improved by early removal of nodal disease. There was no difference in DFI (P = 0.5) or survival (P = 0.3) between these two groups. It is concluded that ELND may provide prognostic information for patients with thick cutaneous melanomas. However, there was no change in DFI or ultimate survival when patients were followed, and nodes removed when clinically positive. The authors do not recommend ELND for patients with thick melanomas because the risk of distant metastases outweighs any benefit of regional node dissection.

Acral melanoma: a review of 185 patients with identification of prognostic variables

One hundred eight-five patients with acral melanoma treated since 1972 were reviewed. These included 53 subungual lesions, 123 plantar lesions, and 9 palmar lesions. Eighty percent presented with stage I disease. Mean age was 57 years. Males outnumbered females 1.1:1. Seventeen percent (17%) were blacks. Actuarial 10-year survival was 58% for stage I patients and 35% for stage II patients. Univariate Cox regression analyses identified 5 prognostic variables affecting survival: stage at diagnosis (P less than 0.001), race (P less than 0.001), ulceration (P = 0.012), Clark's level (P = 0.014), and thickness of the primary lesion (P = 0.013). Factors unrelated to survival included sex of the patient, site (volar vs. subungual), histology, and treatment with amputation. Multivariate analysis for patients with stage I lesions identified race (P = 0.001) and ulceration (P = 0.018) as significant variables, with thickness approaching significance (P = 0.094). In an additional series of 71 patients with melanomas arising from extremity sites near the junction of glabrous and non-glabrous skin, survival was significantly poorer for those arising from glabrous skin (P = 0.024), and reflects a higher incidence of metastatic disease at diagnosis. Specific active immunotherapy was the principal adjuvant used for these patients, and survival was comparable to that reported with regional perfusion therapy. Acral melanoma a) has a strong racial predilection, b) carries a grave prognosis, and c) arises from glabrous skin. It is a clinical entity distinct from other extremity melanomas. Surgical management with either wide excision or amputation is appropriate for the primary lesion.

Late recurrence of malignant melanoma. Analysis of 168 patients

Analysis of 7104 patients with melanoma seen at Duke University identified 168 who experienced their first recurrence 10 or more years after diagnosis, for an incidence of 2.4%. This included patients with all stages of disease. There was no sex, age, or primary site predominance. The mean disease-free interval for cutaneous melanomas was 14.3 years versus 22.3 years for ocular primary melanomas. The prognosis following relapse was related to the site of recurrence. Survival after local or regional node recurrence was often prolonged; survival after distant metastases was usually limited. Patients with ocular primaries had the highest incidence of distant metastases, and the shortest subsequent survival. An additional 483 patients were identified who survived 10 or more years without evidence of recurrence; of these 651 patients with long disease-free intervals, 25% (168 of 651) developed recurrent disease. This demonstrates that a 10-year disease-free interval cannot be considered a cure, and emphasizes the importance of continued annual follow-up.

Implications of leukoregulin to autologous tumor-specific human T-cell populations

Interactions between the cellular and humoral compartments of the human immune system are well documented. Leukoregulin (LR) is a hormone with the ability to upregulate the natural killer (NK) phenomenon by increasing target cell sensitivity to NK lymphocyte cytotoxicity. In the present report, the interactions between LR and human cytotoxic T-lymphocytes (CTLs) are described. Two cultured T-cell populations are specifically cytotoxic for autologous human melanoma and fail to lyse allogeneic melanoma, K562, or autologous peripheral blood lymphocytes (PBLs) in 4 h chromium release assays. Pretreating allogeneic melanoma or K562 with LR resulted in 19-67% lysis at an effector:target (E:T) ratio of 5:1, while no more than 10% lysis was observed without LR. Autologous PBLs were also subject to lysis when pretreated with LR (50% at an E:T of 40:1 with LR, and 2% without LR). The observed effect was dose-related and was most effectively inhibited by autologous cold targets, but persisted in the presence of antibody to human lymphocyte antigen class I antigens (w6/32). Lysis of autologous melanoma was not increased by pretreatment with LR. LR appears to mediate lysis of melanoma, NK targets, and normal PBLs by tumor specific CTLs. The effect is dose-related and non-major histocompatibility complex-restricted. The data do not support a significant role for LR in the normal physiology of human CTLs, but the striking effects in vitro may prove to be experimentally or therapeutically useful.

Malignant melanoma arising during pregnancy. A study of 100 patients

Melanoma is often diagnosed in young adults, a significant proportion of whom are women of child-bearing age. The prognosis of women diagnosed with melanoma during a pregnancy continues to be debated. One hundred patients, ages 19 to 40 years, have been identified who were pregnant at the time of diagnosis of their melanoma. All were treated with local excision. Sixteen per cent underwent elective lymph node dissections. Immunotherapy was administered to 83% of patients. Mean follow-up was 6.8 years from the date of diagnosis. The patients were compared to an age-matched group of 86 women who were not pregnant at the time of diagnosis. Overall mortality during the follow-up period was 25% in the pregnant group and 23% in the control group. Among the pregnant group, there was an increased incidence of lymph node metastases during the follow-up period (39% versus 26%, p = 0.053). Among stage I patients, there was a significantly shorter DFI for the pregnant group (p = 0.039), with 50% of pregnant patients and 67% of control patients free of disease at 10 years. Similarly, among stage 1 patients, the time to development of lymph node metastases was shorter in the pregnant group (p = 0.021). Multivariate analysis demonstrated that pregnancy at diagnosis was significantly associated with the development of metastatic disease (p = 0.008), when controlling for tumor site, thickness, and Clark level. Patients who developed melanoma during pregnancy did not, however, have a significant decrease in survival.

Free jejunal interposition graft for reconstruction of the esophagus

Forty-seven patients underwent pharyngoesophageal reconstruction using a free jejunal interposition graft (FJIG) at Duke University Medical Center from 1978 through 1987. There were 30 men and 17 women with ages ranging from 38 to 87 years old (mean age, 64 years). Twenty-one patients (group A) had no prior surgical procedures, 20 (group B) were reconstructed following radiation and/or surgical failure, with 6 patients (group C) having benign strictures of the upper alimentary tract. Follow-up ranged up to 122 months (mean, 23 months), with 3 patients lost to follow-up, and 4 perioperative deaths (within 3 months of surgery). There were a total of 9 initial graft failures, 4 patients undergoing successful re-implantation, resulting in an overall success rate of 89% (42 of 47). Excluding patients with graft failures, perioperative deaths, and patients lost to follow-up, 33 of 36 patients with a viable FJIG were able to maintain adequate swallowing function yielding a physiologic success rate of 86%. All of the 21 patients dying of recurrent disease had excellent palliation with the FJIG. Of the 7 patients who are alive, only 1 has dysphagia secondary to stricture. In conclusion, it is felt that the FJIG is a sophisticated method of reconstructing large surgical defects of the pharyngoesophagus with a high technical and physiologic success rate.

Generation of human autologous melanoma-specific cytotoxic T-cells using HLA-A2-matched allogeneic melanomas

Autologous tumor-specific cytotoxic T-lymphocytes (CTLs), generated by repeated stimulation with autologous melanoma and expanded in interleukin 2, are major histocompatibility complex restricted. These CTLs recognize a common tumor-associated antigen in the presence of HLA class I determinants, suggesting that allogeneic melanomas which express the restricting HLA-A region antigen could substitute for the autologous tumor in the generation of CTLs. This was investigated in the HLA-A2 system. Four T-cell lines were established by stimulation of lymphocytes with either autologous tumor or an HLA-A2-matched allogeneic melanoma. Allogeneic stimulated CTLs specifically lysed the autologous tumor and demonstrated an identical pattern of HLA-A2 restriction, when compared to the autologous stimulated CTLs. Lysis by the allogeneic stimulated CTLs was blocked by a monoclonal antibody to HLA class I antigens; lysis was also inhibited by both autologous tumor or HLA-A2 allogeneic melanomas when evaluated in cold target competition studies. The allogeneic stimulated CTLs proliferated in response to both autologous tumor and HLA-A2 melanomas, but not in response to HLA-A2 nonmelanomas. By phenotypic analysis these CTLs were CD3+ and predominantly CD8+ cells. We conclude that autologous tumor-specific CTLs can be generated using HLA-A region-matched allogeneic melanomas for stimulation. Since established, HLA-typed melanoma tumor lines can be used in the absence of autologous tumor; this procedure can be applied clinically to a broad patient population and may prove useful in the adoptive immunotherapy of melanoma.

Inhibition of the growth of human melanoma xenografts in nude mice by human tumor-specific cytotoxic T-cells

Melanoma-specific T-cells (CTLs) are specifically cytotoxic for autologous tumor, when assayed in vitro. To examine their effectiveness in vivo, we tested the ability of these human T-cells to inhibit growth of human melanoma xenografts by using a Winn assay. Nude mice receiving specific CTLs (n = 10) demonstrated a dramatic inhibition of tumor growth. All treated mice were tumor-free at day 50 and nine remained tumor-free at day 65, vs. control mice (n = 10) with average tumor volumes of 321 mm3 and 808 mm3, respectively. To control for the possibility that a non-specific response to the human T-cells could inhibit tumor growth, an additional group received allospecific CTLs. There was no inhibition of tumor growth in this group (n = 8), with the average tumor volume of 2,768 mm3 at day 40 vs. 1,882 mm3 in the control group (n = 10). We conclude that these tumor-specific CTLs can inhibit tumor growth in vivo and may prove useful in the adoptive immunotherapy of melanoma.

Modulation of in vitro autologous melanoma-specific cytotoxic T-cell responses by phorbol dibutyrate and ionomycin

Human melanoma-specific, HLA restricted, cytotoxic T-cell lines can be generated by in vitro stimulation and culturing of peripheral lymphocytes, or lymph node cells, with autologous or HLA-A region matched melanomas in the presence of a low concentration (5 U/ml) of IL-2. Stimulation is followed by a period of clonal expansion and differentiation into cytotoxic T-cells specific for melanoma. We investigated the effect of the PKC modulating drug phorbol dibutyrate combined with the calcium ionophore Ionomycin on growth and differentiation of the cell lines. The growth of the T-cell lines was substantially augmented in the presence of the drugs with increases of 10-fold or more in clonal expansion by 3 weeks of culture. The cell lines were IL-2 dependent for growth in the presence or absence of the drugs and the phenotypic distribution remained predominantly CD3+ T-cells of mixed CD4 and CD8 phenotypes. In spite of the increased rate of growth in the presence of the drugs, autologous melanoma-specific cytotoxicity was almost completely abrogated in those cultures. The cells were, however, nonspecifically lytic in the presence of concanavalin A. The melanoma-specific cytotoxic response was completely restored following culture with IL-2 alone. The results suggest that the human tumor-specific cytotoxic T-cell response can be induced and amplified in the presence of immune modulating drugs.

Anorectal melanoma: clinical characteristics and results of surgical management in twenty-four patients

Twenty-four patients with primary anorectal melanoma diagnosed since 1974 have been studied retrospectively. There was a predominance of women (2.4:1): Mean age was 64 years. The most common initial symptom was rectal bleeding, typically misdiagnosed as hemorrhoids. Seventeen patients had stage I cancer when first seen, four had stage II, and three had distant disease. Progressive disease most commonly started as a large pelvic mass, diffuse bilateral pulmonary nodules, or diffuse liver metastases. Twenty patients (83%) died of the disease; none survived more than 6 years. Among the patients who died of the disease, median survival was 1.9 years. Median survival for patients with stage I disease (29 months) was longer than that for patients with stage II disease (11 months; p less than 0.05) or stage III disease (9 months). Twelve patients were treated initially with abdominoperineal resection (APR), and three additional patients underwent APR to manage recurrent local or regional disease that developed later in the clinical course. Among evaluable patients with stage I disease initially managed with APR, 50% developed recurrent local-regional disease (mean disease-free interval, 23 months), compared with 100% of those who underwent more limited surgery (mean disease-free interval, 16 months). Even after APR, however, distant metastases were common, and there was no prolongation of survival for patients treated with APR. Primary melanoma of the anorectum has a high metastatic potential and carries a grave prognosis. APR appears to have some effect in controlling local and regional disease, but prolongation of survival will depend on both earlier diagnosis and development of more successful therapeutic approaches.

Melanoma-specific cytotoxic T cells generated from peripheral blood lymphocytes. Implications of a renewable source of precursors for adoptive cellular immunotherapy

Cytotoxic T lymphocytes (CTL) specific for autologous human melanoma have been generated in vitro from peripheral blood lymphocytes (PBL) of five patients with resectable stage II malignant melanoma. The PBL were cultured with 5u/ml recombinant IL-2 and were repeatedly stimulated with irradiated fresh or cultured autologous tumor cells. Cytotoxicity was determined by four-hour chromium release assays. Specific cytotoxicity developed in 30 to 40 days, after three or four stimulations with tumor. The PBL-derived CTL are CD3+ and are mixed for CD4+ and CD8+ phenotypes. They lysed autologous melanoma and failed to lyse allogeneic melanoma, K562, or autologous lymphocytes. The lysis of autologous tumor was maintained for more than 4 months. The cells proliferated in response to autologous, but not allogeneic melanoma cells, in a dose-dependent manner. Lysis of the autologous tumor target was inhibited with w6/32, a monoclonal antibody to HLA Class I antigens. It is concluded that PBL may serve as a plentiful and renewable source of precursor cells for the generation of autologous tumor-specific CTL, which may be useful in specific adoptive cellular immunotherapy of melanoma.

The role of HLA class I antigens in recognition of melanoma cells by tumor-specific cytotoxic T lymphocytes. Evidence for shared tumor antigens

CTL lines were established in vitro by stimulating patient lymphocytes with autologous melanoma cells in the presence of IL-2. Resulting CTL lines lysed autologous melanoma and failed to lyse several allogeneic melanomas or K562. The mechanism of target cell recognition by autologous tumor-specific CTL was evaluated in this system, using several CTL lines: DT6, DT105, DT141, DT166, DT169, and DT179. Autologous melanoma lysis was inhibited by W6/32, mAb directed against HLA class I Ag, but not by L243, mAb directed against HLA class II Ag. CTL from DT6, DT141, DT166, DT169, and DT179 lysed fresh and cultured allogeneic melanomas, which shared the HLA-A2 Ag, but failed to lyse allogeneic melanomas, which shared B-region or C-region Ag, or shared no HLA class I Ag. CTL from DM141 lysed DM93, which shared A2 and Bw6, but failed to lyse DM105, which shared only Bw6. DM105 CTL failed to lyse allogeneic melanomas that shared HLA-A1, or that shared B or C region Ag, but they did lyse allogeneic melanoma DM49, which expressed an A region Ag that either was A10 or was serologically cross-reactive with A10. A T cell leukemia line, three EBV transformed B cell lines, and a pancreatic cancer line, all of which expressed HLA-A2, were not lysed by DM6 or DM179 CTL. Furthermore, HLA-matched nonmelanomas failed to inhibit autologous tumor lysis in cold target inhibition assays, whereas an HLA-A2+ allogeneic melanoma, DM93, inhibited autologous tumor lysis as effectively as the autologous tumor itself. HLA-A2, and possibly other HLA-A-region Ag, appear to function in HLA-restricted recognition of shared melanoma associated Ag by CTL.

The role of HLA class I antigens in recognition of melanoma cells by tumor-specific cytotoxic T lymphocytes. Evidence for shared tumor antigens

CTL lines were established in vitro by stimulating patient lymphocytes with autologous melanoma cells in the presence of IL-2. Resulting CTL lines lysed autologous melanoma and failed to lyse several allogeneic melanomas or K562. The mechanism of target cell recognition by autologous tumor-specific CTL was evaluated in this system, using several CTL lines: DT6, DT105, DT141, DT166, DT169, and DT179. Autologous melanoma lysis was inhibited by W6/32, mAb directed against HLA class I Ag, but not by L243, mAb directed against HLA class II Ag. CTL from DT6, DT141, DT166, DT169, and DT179 lysed fresh and cultured allogeneic melanomas, which shared the HLA-A2 Ag, but failed to lyse allogeneic melanomas, which shared B-region or C-region Ag, or shared no HLA class I Ag. CTL from DM141 lysed DM93, which shared A2 and Bw6, but failed to lyse DM105, which shared only Bw6. DM105 CTL failed to lyse allogeneic melanomas that shared HLA-A1, or that shared B or C region Ag, but they did lyse allogeneic melanoma DM49, which expressed an A region Ag that either was A10 or was serologically cross-reactive with A10. A T cell leukemia line, three EBV transformed B cell lines, and a pancreatic cancer line, all of which expressed HLA-A2, were not lysed by DM6 or DM179 CTL. Furthermore, HLA-matched nonmelanomas failed to inhibit autologous tumor lysis in cold target inhibition assays, whereas an HLA-A2+ allogeneic melanoma, DM93, inhibited autologous tumor lysis as effectively as the autologous tumor itself. HLA-A2, and possibly other HLA-A-region Ag, appear to function in HLA-restricted recognition of shared melanoma associated Ag by CTL.

Melanoma patient antibody responses to melanoma tumor-associated antigens defined by murine monoclonal antibodies

Sera from melanoma patients undergoing immunization with three distinct immunogens were evaluated for development of IgG antibody specific for the melanoma tumor-associated antigens (TAAs) GD3 and 250-kd glycoprotein (high molecular weight; HMW). Of 99 patients receiving either irradiated allogeneic melanoma cells admixed with bacillus Calmette-Guérin, vaccinia viral oncolysate melanoma cell membranes, or cholesterol hemisuccinate-modified melanoma cells, 12 were determined to have responded against GD3 and 17 against the HMW TAA. This reactivity was measured using both direct binding to purified TAA and specific inhibition of binding of murine monoclonal antibodies R24 and Me-1-14 for GD3 and HMW TAA, respectively. Preimmune sera from these patients did not react with these TAAs, nor did preimmune sera or follow-up sera from melanoma patients electing not to receive immunotherapy. These results suggest that melanoma patients can be immunized against these TAAs as presented on the melanoma cell membrane in an immunotherapy setting and that immunization using purified TAAs might likewise be feasible.

Serological response of non-human primates to human melanoma disialoganglioside GD3

The immunogenicity of the disialoganglioside, GD3, a melanoma-tumor-associated antigen, has been evaluated in non-human primates. Sera from four chimpanzees and two monkeys were evaluated for anti-GD3 antibody activity by solid-phase radioimmunoassay using GD3 and control gangliosides as targets. Serum from one monkey, immunized with cells from a melanoma cell line, was strongly reactive with GD3, having a titer of greater than 2500. In contrast, serum from this animal was non-reactive with several other gangliosides including the structurally similar GM3. Anti-GD3 reactivity was also demonstrable, albeit in low titer, in the sera of an additional monkey and a chimpanzee. Each of these animals had likewise been immunized using cells from melanoma cell lines. On the basis of these observations, suggestive of a primate anti-GD3 antibody response, we initiated a series of immunizations of chimpanzee using purified GD3 bound to Salmonella minnesota, R595. IgG reactive with melanoma cells in the cell-binding assay was first detected in sera collected after 4 immunizations and increased in titer against each reactive melanoma cell line during the immunizations. Reactivity of this serum with melanoma cell lines demonstrated a direct correlation with the expression of GD3 by the respective cell line. Anti-GD3 reactivity was evident in solid-phase radioimmunoassay against purified GD3 beginning with serum collected after 11 immunizations. By comparison with its binding to the control ganglioside panel, this serum demonstrated strong specificity for GD3 (titer = 640) while having only marginal reactivity with GM3 (titer = 40). Immune serum from this animal was also able specifically to block subsequent binding of a murine IgM anti-GD3 antibody (DMab7) to target GD3 in solid-phase radioimmunoassay. Together, these observations suggest that GD3, in the form of a purified molecule bound to a bacterial matrix or as part of the intact melanoma cell membrane, can be immunogenic in non-human primates, and is able to elicit an antibody response of appropriate specificity.

Stage II malignant melanoma: presentation of a prognostic model and an assessment of specific active immunotherapy in 1,273 patients

The ability to redefine risk factors and to predict prognosis in patients with malignant melanoma at the time they manifest nodal metastasis can be a benefit to the patient emotionally and to the physician therapeutically. A retrospective review of 1,273 patients with stage II malignant melanoma was performed at our institution. The most significant prognostic factors in a simultaneous hazard Cox multivariate analysis, predicting melanoma-related mortality among stage II patients, were the number of positive nodes (P less than 0.0001), age (P = 0.0004), site of the primary lesion (P = 0.0036), disease-free interval (P = 0.016), thickness of the primary lesion (P = 0.017), and sex of the patient (P = 0.0616). We have developed a model for predicting survival of stage II patients, designed for use in the clinic setting. Its application in a computer system makes it accessible and understandable. The most favorable risk group (18% of the population) has actuarial 5- and 10-year survival rates of 58% and 49%, respectively, from the time of the nodal metastasis. The least favorable risk group (7% of the population) has 5- and 10-year survival rates of 15% and 10%, respectively. There are three intermediate risk groups. All groups differ prognostically (P less than 0.04). The principal adjuvant therapy offered to these patients was specific active immunotherapy, which appears to have a 10-20% survival benefit in stage II patients with greater than one positive node, when compared with institutional controls. The apparent survival benefit of the immunotherapy supports continued clinical investigation of its therapeutic potential.