[Simultaneous infusion of vinorelbin and taxol as first-line chemotherapy in metastasized breast cancer]

PURPOSE

To evaluate the activity and toxicity of simultaneous infusion of vinorelbine (VNB) and paclitaxel (T) as first line chemotherapy in advanced breast cancer patients (pts).

PATIENTS AND METHODS

33 pts with histologically proven advanced breast cancer were treated with VNB 25 mg/m2 and T 150 mg/m2, both drugs given by i.v. infusion over 3 hours, with cycles repeated every 3 weeks. Granulocyte-colony-stimulating factor (G-CSF), 300 micrograms subcutaneously, was given on days 7 to 12 of each cycle in the first 10 patients.

RESULTS

From October 1995 to July 1996, 33 untreated pts entered the study. Characteristics of the pts were the following: median age 53 years (29-71); median WHO performance status 1 (0-3); pre/postmenopausal 8/25; prior adjuvant chemotherapy 16; prior radiotherapy 8; dominant disease sites: soft tissue in 6; bone in 7, viscera in 19; number of metastatic sites: 1 in 18, 2 in 9, 3 in 6 pts. In 31 evaluable pts we observed: 1 CR (3%) and 14 PR (45%), for an overall response rate of 48%. Median time to response was 2 months; median time to progression and median survival were 7 and 22+ months, respectively. Median number of cycles was 6. Myelosuppression was the dose-limiting toxicity, with G 4 neutropenia occurring in 22% of the pts and neutropenic fever in 6% of the pts. Other toxicities were generally mild with nausea in 52% of the pts; mucositis in 15%; constipation in 12%; peripheral neuropathy in 46.5%. Alopecia was universal.

CONCLUSIONS

Simultaneous infusion of VNB and T is well tolerated and active in untreated patients with advanced breast cancer. Median survival (22+ months) is similar to that reported with anthracycline-containing regimens, although response rate appears to be lower. It is likely that higher response rates may be achieved with a higher dose-intensity.

S100 protein serum levels in cutaneous malignant melanoma

We investigated the utility of serum S100 determined by means of immunoradiometric assay in a cohort of 438 patients affected by cutaneous melanoma (126 untreated and 312 previously treated). Using 0.2 microg/l cut-off value, determined in 134 healthy blood donors, the sensitivity was 4.2% in stage I patients (4/94), 5.3% in stage II patients (1/19), and 38.5% in stage III patients (5/13). Even though the sensitivity increased progressively from stage I to stage II and III, these differences were not statistically significant. The prognostic significance of S100 evaluation at diagnosis was investigated in terms of survival but no statistical correlation between S100 basal levels and survival was found. In the 312 previously treated patients serum S100 levels were correlated to disease extent, high levels of the marker were observed in 42.8% (9/21) of patients with local recurrence, in 32% (16/50) of patients with lymph node and/or in-transit metastases, in 77.3% (17/22) of patients with distant metastases, and in patients with NED, the specificity of the marker was 96.8% (212/219). The difference between these groups were statistically significant. In conclusion, S100 protein was abnormally high in patients with metastatic malignant melanoma. Serial S100 measurements in a follow-up study are necessary to test the importance of the protein in the management of patients with metastatic malignant melanoma.

Evaluation on serum 2'-5'oligoadenylate synthetase (2'-5'oligoAS) and beta 2 microglobulin (B2M) in patients with nodal metastases from cutaneous malignant melanoma treated with rIFN-alpha 2A

IFN-alpha is a promising adjuvant agent in patients with regional melanomatous metastases (stage IIIB). The aim of this study was to verify whether serum evaluation of the interferon induced proteins 2'-5'oligoAS and B2M can predict the clinical response to rIFN-alpha 2A therapy.

PATIENTS AND METHODS

Forty-two patients who had undergone radical dissection of nodal metastases were evaluated. All patients received adjuvant rIFN-alpha 2A (3 million units s.c. three times weekly) for 3 years or until progression. The patients were followed for a medium period of 43 months (range 19-46). During follow-up 22 of the 42 patients had disease progression. In all patients blood samples were obtained before starting adjuvant therapy and after 1 and 6 months of therapy with rIFN-alpha 2A. 2'-5' oligoAS and B2M were measured by radioimmunoassay.

RESULT

During the first month of adjuvant therapy with rIFN-alpha 2A the serum levels of 2'- 5' oligoAS increased 10-fold, and this trend was maintained in the following 6 months. Similar results were obtained for B2M serum levels. However, we did not find any significant difference in AS and B2M serum levels between responders and non-responders.

CONCLUSION

Our results, therefore, indicate that AS and B2M are markers of the biological activity of administered IFN but that they have little efficacy in predicting the clinical outcome of the treated patients.

Immunogenicity of the ALLAVGATK (gp100[17-25]) peptide in HLA-A3.1 melanoma patients

A T cell line recognizing autologous and allogeneic HLA-A3.1 melanomas was obtained from a disease-free melanoma patient (patient 15392). By transfection of a tumor cDNA library and in vitro sensitization experiments, the ALLAVGATK gp100/Mel17-derived peptide was found to be the epitope recognized by this melanoma-specific T cell line. The role of the ALLAVGATK peptide in the systemic immune response to melanoma of this patient was evaluated. When pulsed on the autologous peripheral blood mononuclear cells, the ALLAVGATK peptide generated tumor-specific HLA-A3-restricted T lymphocytes and a single restimulation in vitro was sufficient to raise gp100-specific T lymphocytes, indicating a high frequency of epitope-specific T cells. gp100-specific T cells were also induced from T lymphocytes purified from tumor-invaded lymph nodes (tumor-associated lymphocytes, TAL). TAL-derived effectors displayed lower peptide affinity and lower tumor recognition than effectors elicited from peripheral blood lymphocytes (PBL). To further evaluate its immunogenicity, ALLAVGATK was used to stimulate PBL derived from six additional HLA-A3.1 melanoma patients and seven healthy donors. After 7 weeks of peptide stimulation in vitro the generation of anti-gp100 and tumor-specific T cell lines was achieved in one out of the six patients analyzed. Taken together these data indicate that an in vivo priming leading to a systemic immunity against gp100 in HLA-A3 melanoma patients may occasionally occur and that the immunogenicity of ALLAVGATK peptide in melanoma patients is comparable to that of other HLA-A2-restricted epitopes derived from gp100/Mel 17 protein.

Immediate or delayed dissection of regional nodes in patients with melanoma of the trunk: a randomised trial. WHO Melanoma Programme

BACKGROUND

The use of elective regional node dissection in patients with cutaneous melanoma without any clinical evidence of metastatic spread is still debated. Our aim was to evaluate the efficacy of immediate node dissection in patients with melanoma of the trunk and without clinical evidence of regional node and distant metastases.

METHODS

An international multicentre randomised trial was carried out by the WHO Melanoma Programme from 1982 to 1989. The trial included only patients with a trunk melanoma 1.5 mm or more in thickness. After wide excision of primary melanoma, patients were randomised to either immediate regional node dissection or a regional node dissection delayed until appearance of regional-node metastases.

FINDINGS

Of the 252 patients entered, 240 (95%) were eligible and evaluable for analysis. 122 of these were randomised to immediate node dissection. 5-year survival observed in patients who had delayed node dissection was 51.3% (95% CI 41.7-60.1) compared with 61.7% (52.0-70.1) of patients who had immediate node dissection (p=0.09). 5-year survival rate in patients with occult regional node metastases was 48.2% (28.0-65.8) and 26.6% (13.4-41.8, p=0.04) in patients in whom the regional node dissection was delayed until the time of appearance of regional node metastases. Multivariate analysis showed that routine use of immediate node dissection had no impact on survival (hazard ratio 0.72, 95% CI 0.5-1.02), whilst the status of regional nodes affected survival significantly (p=0.007). The patients with regional nodes that became clinically and histologically positive during follow-up had the poorest prognosis.

INTERPRETATION

Node dissection offers increased survival in patients with node metastases only. Sentinel node biopsy may become a tool to identify patients with occult node metastases, who could then undergo node dissection.

[Sequential therapy with methotrexate and 5-fluorouracil in patients with advanced colorectal cancer pretreated with 5-fluorouracil plus folinic acid]

PURPOSE

To evaluate the efficacy and toxicity of a sequential low-dose methotrexate (MTX) and 5-fluorouracil (5FU) regimen in the palliative treatment of patients with advanced colorectal cancer.

PATIENTS AND METHODS

Enrolled in the study were patients with advanced colorectal cancer, refractory to 5FU + FA. Patients were treated with MTX 40 mg/m2 i.v. bolus d 1 and 8, 5FU 700 mg/m2 i.v. bolus d 2 and 9 (24 hours after MTX bolus). The cycle was repeated every 4 weeks.

RESULTS

48 patients entered the study, and 45 are evaluable. The overall response rate was 15% with 1 complete response and 6 partial responses. Eight patients obtained disease stabilization. Median time to progression was 9 months. Toxicity was mild. Grade 3 stomatitis was observed in 7 (15%) patients.

CONCLUSIONS

Sequential MTX/5FU is a well tolerated regimen with mild antitumor activity in refractory advanced colorectal patients.

Evaluation of clinical efficacy and tolerability of intravenous high dose thymopentin in advanced melanoma patients

Thymopentin (TP5) has been recently evaluated as an immunotherapeutic agent for the treatment of cancer. Melanoma is a highly immunogenic malignancy, and in our previous studies the treatment of metastatic melanoma with TP5 showed encouraging results. In the present study, we evaluated the clinical efficacy and tolerability of high dose intravenous TP5 in 16 patients with melanoma which had metastasized to cutaneous and subcutaneous tissue. All patients were given 1 g intravenous TP5 every second day for 7 weeks and were then evaluated; responders were given a subsequent course of 2 g intravenous TP5 every second day for 5 weeks. Six patients showed a partial response after the first course and were given the second course: one patient achieved a complete response, while the other five remained in partial response at the end of the treatment. The mean duration of response was 7.5 months. No drug side effects were observed. Histopathological and immunohistochemical evaluation of regressing metastatic nodules showed the presence of tumour-infiltrating lymphocytes, necrosis, sclerosis, intratumoral vascular proliferation and microthrombosis. Immunophenotyping of lymphoid infiltrates demonstrated the prevalence of CD4+ and CD45RO+ T-lymphocytes in one patient. We conclude that high dose intravenous TP5 three times a week may induce a clinical response in patients with cutaneous and subcutaneous metastases of melanoma without relevant side effects.

Combined effects of interferon-alpha2a and 13-cis-retinoic acid on human melanoma cell growth and STAT protein expression

We assessed the antiproliferative effects of human recombinant interferon-alpha2a (IFNalpha2a) and 13-cis-retinoic acid (13cis-RA) on two human melanoma cell lines (JR8 and M14). Both cell lines showed a very modest sensitivity to IFNalpha2a and 13cis-RA as single agents. In JR8 cells, the combination of the two compounds consistently produced simple additive effects. In contrast, different effects of the combination were recorded in the M14 cell line depending on the treatment schedule. Specifically, an additive interaction was observed when IFNalpha2a and 13cis-RA were given in sequence, independently of the order of drug administration, whereas a supra-additive antiproliferative effect was seen when cells were simultaneously exposed to the two drugs. Exposure to 1000 IU/ml IFNalpha2a markedly increased the nuclear expression of signal transducers and activators of transcription (STAT) proteins in both cell lines. By itself 10 microM 13cis-RA did not affect STAT protein expression or modify the extent of activation of such proteins by IFNalpha2a. Results from our study showed an enhancement of the antiproliferative activity of IFNalpha2a and 13cis-RA when given in combination and suggest that such an enhancement is not mediated by a concomitant effect of 13cis-RA on STAT protein activation.

Recognition of melanoma-derived antigens by CTL: possible mechanisms involved in down-regulating anti-tumor T-cell reactivity

Several T cell-recognized epitopes presented by melanoma cells have been identified recently. Despite the large array of epitopes potentially available for clinical use, it is still unclear which of these antigens could be effective in mediating anti-tumor responses when used as a vaccine. Preliminary studies showed that immunization of melanoma patients with epitopes derived from proteins of the MAGE family may result in significant clinical regressions. However, no sign of systemic immunization could be observed in peripheral blood of treated patients. Conversely, significant immunization (detected as increased antigen-specific CTL activity in peripheral blood) was obtained by vaccinating HLA-A2.1+ melanoma patients with the immunodominant epitope (residues 27-35) of the differentiation antigen MART-1, but this immunization was not accompanied by a significant clinical response. To implement immunotherapeuties capable of significantly impacting disease outcome, it is necessary to identify the potential mechanisms responsible for the failure of some antigens to mediate significant anti-tumor responses in vivo. In the case of the MART-1(27-35) epitope, we hypothesize that one of these mechanisms may be related to the existence of natural analogs of this peptide in other human normal proteins.

Dexrazoxane cardioprotection in advanced breast cancer patients undergoing high-dose epirubicin treatment

PURPOSE

We performed a randomized trial to evaluate the cardioprotective effect of dexrazoxane (DEX) in advanced breast cancer patients (ABC) treated with high single-dose epirubicin (EPI). A secondary objective was to determine the role of radioimmunoscintigraphy (RIS) in the assessment of epirubicin cardiotoxicity.

PATIENTS AND METHODS

Ninety-five patients with ABC were treated with EPI 160 mg/m2 by i.v. bolus every 3 weeks with or without DEX, 1,000 mg/m2 i.v. Cardiac monitoring included multigated radionuclide (MUGA) scan with determination of resting left ventricular ejection fraction (LVEF), and RIS with 111-Indium antimyosin monoclonal antibodies.

RESULTS

The overall response rate was 69% in the EPI arm and 67% in the EPI + DEX arm; median time to response and median time to progression were identical in both arms, being 2 and 8 months, respectively. Median survival was 19 months versus 29 months (p 0.21), respectively. DEX did not appear to contribute to extracardiac EPI toxicity. Congestive heart failure occurred only in the EPI arm (2 instances). LVEF significantly decreased from baseline only in the EPI group. An abnormal tracer uptake at RIS was observed early in both arms, but the increase in heart to lung ratio was much more evident in the control group.

CONCLUSIONS

DEX significantly protects against the development of high dose epirubicin cardiotoxicity apparently without evidence of an adverse impact on antitumor activity and non cardiac toxicity. RIS is a very sensitive technique in detecting anthracycline cardiac damage, but its specificity is low and cannot be considered alone a primary test for guiding anthracycline treatment.

Autologous dendritic cells derived from CD34+ progenitors and from monocytes are not functionally equivalent antigen-presenting cells in the induction of melan-A/Mart-1(27-35)-specific CTLs from peripheral blood lymphocytes of melanoma patients with low frequency of CTL precursors

Peptide presentation by autologous dendritic cells (DCs) is a new tool to activate tumor antigen-specific T cells in melanoma patients. However, it is not known whether autologous DCs, differentiated by two of the most efficient protocols (from CD34+ progenitors or from monocytes), are equally effective as professional antigen-presenting cells (APCs) when the patients have a low frequency of peptide-specific precursors. To this end, a limiting dilution assay was applied to evaluate the frequency of antigen-specific CTL precursors (CTLps) in peripheral blood of HLA-A*0201+ melanoma patients. Then, from two melanoma patients showing low frequency of CTLps to melanoma antigen-A/melanoma antigen recognized by T cell (Melan-A/Mart-1)(27-35) peptide, autologous DCs were differentiated from granulocyte colony-stimulating factor-mobilized CD34+ progenitors or from monocytes. CD34+- and monocyte-derived DCs were characterized by a similar proportion of CD1a+ cells expressing HLA class II antigens and CD54, CD80, and CD86 molecules. Both types of DC presented Melan-A/Mart-1(27-35) and tyrosinase(369-377) peptides to melanoma-specific CTL clones and were equally effective as peptide-pulsed APCs in the activation of influenza A matrix(58-66)-specific CTLs from high-frequency precursors (1294/10(6) and 1789/10(6) lymphocytes in the two patients). However, efficient activation of Melan-A/Mart-1(27-35)-specific CTLs from low-frequency precursors (158/10(6) and 77/10(6) lymphocytes) of the two patients was markedly dependent on the use of peptide-loaded CD34+-derived DCs. These results suggest that CD34+- and monocyte-derived DCs are not functionally equivalent APCs for the activation of low-frequency peptide-specific CTLps.

Active immunization of metastatic melanoma patients with interleukin-2-transduced allogeneic melanoma cells: evaluation of efficacy and tolerability

From January 1994 to July 1996 we immunized metastatic melanoma patients with HLA-A2-compatible, interleukin-2 (IL-2)-secreting, immunogenic melanoma lines in an attempt to induce a systemic reaction that might also affect distant melanoma lesions. Twelve patients (6 male and 6 female) aged from 28 to 72 years, affected with visceral and/or subcutaneous (s.c.) melanoma metastases, were treated. Two different HLA-A2+ melanoma lines were transduced with the human IL-2 gene (14932/IL-2 and 1B6/IL-2) and used as vaccine. Two groups of 4 patients each were injected s.c. with 5 x 10(7) and 15 x 10(7) irradiated 14932/IL-2 melanoma cells respectively, whereas a third group received 5 x 10(7) cells of the second line (1B6/IL-2). All patients received the vaccine on days 1, 13, 26; if no progression was evident, further immunizations were administered at monthly intervals. All patients were assessable for clinical response after at least three injections of the vaccine. In 4 cases a stabilization of disease lasting from 2 to 6 months was observed: in 2 of them a mixed type of response to treatment was noted with simultaneous evidence of regressing and non-responding lesions in the same patients. No signs of clinical response were found in the remaining patients. Nine patients died of disease between 3 and 24 months after the onset of therapy, whereas 3 were alive 3 months after the end of therapy. The local and systemic side-effects of treatment were mild. These results indicate that vaccination with cells bearing the appropriate antigens and releasing IL-2 locally can produce weak clinical responses, but also indicate that better results may be achieved through modifications of the vaccine, the schedule of immunization and/or a more appropriate selection of patients.

Pharmacokinetics and effects on plasma retinol concentrations of 13-cis-retinoic acid in melanoma patients

The pharmacokinetics of 13-cis-retinoic acid (13cisRA) and its effects on retinol plasma levels were investigated after the first and the last doses in melanoma patients, who participated in a study run to assess tolerance over a long period of a treatment schedule of 13cisRA associated with recombinant interferon alpha2a (rIFN-alpha2a). Melanoma patients with regional node metastases after radical surgery were randomized to be treated for 3 months with rIFN-alpha2a, 3 x 10(6) IU s.c. every other day, associated with oral 13cisRA at doses of 20 mg day(-1) (five patients) or 40 mg every other day (seven patients). Maximum 13cisRA blood concentrations usually occurred 4 h after drug administration, with average values of 406 and 633 ng ml(-1) (i.e. 1.3 and 2.1 microM) after the 20 and 40 mg dose respectively. The average half-life (t(1/2)) was approximately 30 h. The maximum concentration, the t(1/2) and the area under the concentration-time curves from 0 to 48 h (AUC(0-48)) of 13cisRA did not change after multiple dosing, whereas the AUC(0-48) of its major blood metabolite, 4-oxo-13-cis-retinoic acid, increased. Immediately after 13cisRA treatment, retinol plasma levels started to decline and they reached the lowest values (approximately 20% reduction) shortly after the time of maximum 13cisRA concentrations (i.e. 4-12 h after drug intake). Afterwards, values returned to baseline. The amount of retinol reduction in time was correlated with 13cisRA maximum concentrations.

Distal intramural spread in adenocarcinoma of the lower third of the rectum treated with total rectal resection and coloanal anastomosis

PURPOSE

This study was designed to evaluate the frequency of microscopic distal intramural spread in rectal adenocarcinoma and its correlation to other histopathologic prognostic factors.

METHODS

We examined 55 patients with adenocarcinomas of the lower one-third of the rectum and measured the extent of distal intramural spread in the submucosa and/or muscular layer in comparison with Dukes Stage, diameter of tumor, distance of distal margin of resection from tumor, depth of infiltration into perirectal adipose tissue, nodal status, neoplastic infiltration of lymphatic vessels, blood vessels, and nervous branches.

RESULTS

Distal intramural spread was found in 40 percent of patients, 77 percent of whom had advanced tumors with nodal metastases. Distal intramural spread appeared to be strictly related to tumor size (superior to 40 mm), infiltration of the perirectal adipose tissue, multiple positive lymph nodes, presence of neoplastic emboli in the intramural lymphatic vessels, and neoplastic invasion of the nervous branches. Local recurrence occurred in one Dukes Stage B patient with a positive distal margin of resection and in four patients with a negative distal margin of resection: three Dukes Stage C and one Dukes Stage B patients with neoplastic involvement of the circumferential margin of resection of the mesorectum.

CONCLUSION

These preliminary data suggest that distal intramural spread may carry little importance in determining local recurrence of rectal adenocarcinoma.

Limited antitumor T cell response in melanoma patients vaccinated with interleukin-2 gene-transduced allogeneic melanoma cells

We have immunized advanced melanoma patients with a HLA-A2-compatible human melanoma line genetically modified to release interleukin-2 (IL-2), to elicit or increase a T cell-mediated anti-melanoma response that may affect distant lesions. Twelve stage-IV patients were injected subcutaneously at days 1, 13, 26, and 55 with IL-2 gene-transduced and irradiated melanoma cells at doses of 5 or 15 x 10(7) cells. Both local and systemic toxicities were mild, consisting of transient erythema at the vaccination site; fever occurred in a minority of patients. Three mixed responses were recorded. Seven patients were evaluable for immunological studies. Mixed tumor-lymphocyte cultures carried out with different allogeneic HLA-A2-matched melanoma lines as stimulators and targets revealed an increase in the MHC-unrestricted, but no changes in the MHC-restricted, cytotoxicity in peripheral blood lymphocytes (PBL) obtained after vaccination as compared with those obtained before vaccination. Increased recognition of the tyrosinase 368-376 peptide occurred in post-vaccination PBL of one patient, whereas a weak increase in recognition of the gp100 280-288 peptide was detectable in another patient; these 2 patients also recognized the gp100 457-466 peptide. After in vitro, stimulation with the only available autologous melanoma line, CD4+ cells with autologous tumor-specific cytotoxicity and ability to release interferon-gamma (IFN-gamma) were found in post- but not in pre-vaccination PBL. In the same patient, as well as in another patient, limiting dilution analysis showed that vaccination resulted in an increased frequency of melanoma-specific cytotoxic T lymphocyte (CTL) precursors. These results indicate that vaccination with cells releasing IL-2 locally can expand a T cell response against antigen(s) of autologous, untransduced tumor, although this response occurred in a minority of the melanoma patients studied.

Multiple melanoma-associated epitopes recognized by HLA-A3-restricted CTLs and shared by melanomas but not melanocytes

The molecular characterization of melanoma-associated Ags allowed the definition of several HLA class I-presented peptides recognized by T cells. However, no HLA-A3.1-restricted melanoma epitopes have been identified to date. To gain insight into the HLA-A3.1-restricted T cell epitope repertoire of human melanoma, we analyzed the immunologic reactivity of CTLs isolated from tumor-involved or tumor-free lymph nodes in two HLA-A3.1+ melanoma patients. Three CTL lines, clonal or highly oligoclonal in their TCR composition, and two CTL clones were selected for HLA class I-restricted lysis of the autologous tumor and then tested for the recognition of HLA-A3+ and HLA-A3- normal or neoplastic cells of the melanocyte lineage. One CTL recognized a unique HLA-A3.1-restricted Ag expressed only by the autologous tumors, while all the other CTLs defined three HLA-A3.1 epitopes shared by melanomas, but not by melanocytes. Moreover, the epitopes of two CTL lines with different specificity were reconstituted by nonoverlapping fractions of HLA-A3+ melanoma-derived peptides resolved by reverse phase-HPLC, indicating that distinct naturally processed peptides were specifically recognized on melanoma cells in association with HLA-A3.1 molecules. These novel lineage-unrelated HLA-A3.1-restricted melanoma epitopes do not derive from MAGE, BAGE, or GAGE gene families, as evaluated by the COS-7 transfection assay. Our data show that CTLs may recognize HLA-A3.1-class 1 complexes presenting melanoma (but not melanocyte)-associated epitopes that are either unique to a given patient's tumor or that are shared between multiple melanomas.

Multiple melanoma-associated epitopes recognized by HLA-A3-restricted CTLs and shared by melanomas but not melanocytes

The molecular characterization of melanoma-associated Ags allowed the definition of several HLA class I-presented peptides recognized by T cells. However, no HLA-A3.1-restricted melanoma epitopes have been identified to date. To gain insight into the HLA-A3.1-restricted T cell epitope repertoire of human melanoma, we analyzed the immunologic reactivity of CTLs isolated from tumor-involved or tumor-free lymph nodes in two HLA-A3.1+ melanoma patients. Three CTL lines, clonal or highly oligoclonal in their TCR composition, and two CTL clones were selected for HLA class I-restricted lysis of the autologous tumor and then tested for the recognition of HLA-A3+ and HLA-A3- normal or neoplastic cells of the melanocyte lineage. One CTL recognized a unique HLA-A3.1-restricted Ag expressed only by the autologous tumors, while all the other CTLs defined three HLA-A3.1 epitopes shared by melanomas, but not by melanocytes. Moreover, the epitopes of two CTL lines with different specificity were reconstituted by nonoverlapping fractions of HLA-A3+ melanoma-derived peptides resolved by reverse phase-HPLC, indicating that distinct naturally processed peptides were specifically recognized on melanoma cells in association with HLA-A3.1 molecules. These novel lineage-unrelated HLA-A3.1-restricted melanoma epitopes do not derive from MAGE, BAGE, or GAGE gene families, as evaluated by the COS-7 transfection assay. Our data show that CTLs may recognize HLA-A3.1-class 1 complexes presenting melanoma (but not melanocyte)-associated epitopes that are either unique to a given patient's tumor or that are shared between multiple melanomas.

Differences in frequency distribution of HLA-A2 subtypes between North American and Italian white melanoma patients: relevance for epitope specific vaccination protocols

Cytotoxic T lymphocytes (CTL) associated in vivo with tumor regression recognize the product of nonmutated genes expressed by most melanoma cells as peptides bound to human leukocyte antigen (HLA) molecules. Multiple HLA-A*0201 restricted peptides derived from melanoma associated antigens (MAA) have been described, and peptide-based vaccination protocols against melanoma are being developed worldwide for the treatment of HLA-A2 melanoma patients based on the assumption that most serologically typed HLA-A2+ individuals will be suitable for such vaccinations. Serologic typing of HLA-A2, however, encompasses a family of at least 17 related alleles recognized by molecular typing techniques and differing at one or more functional residues of the HLA class I molecule. We have recently shown that naturally occurring single-residue variants of HLA-A*0201 are responsible for significant differences in CTL response to MAA-peptide stimulation. Existing data for HLA-A*02 subtype frequencies among whites (who are most affected by melanoma) derive from analyses of Northern European and North American populations that are of similar heritage and predict an exceedingly rare (< 5%) frequency of non-HLA-A*0201 alleles. Melanoma however, affects other white populations in which the prevalence of HLA-A*02 alleles could be more variable. This study was done to identify HLA-A*02 subtypes and their prevalence in two ancestrally different white melanoma populations. HLA-A*02 subtype frequencies were compared by polymerase chain reaction between serologically HLA-A2+ melanoma patients referred for treatment to the Istituto Nazionale Tumori of Milan (n = 93), Italy or the National Cancer Institute, Bethesda, MD, U.S.A. (n = 100). This analysis demonstrated differences in subtype specificity and distribution between the two populations, with a significantly higher percentage of non HLA-A*0201 subtypes in the Italian population. Only 2% of serologically HLA-A2+ Northern American white melanoma patients did not express HLA-A*0201. In contrast, 15% of HLA-A2+ Italian patients were not HLA-A*0201 (p2 value = 0.001). As allele-specific/peptide-based vaccination protocols are presently pursued at several institutions, a proportion of patients might be inappropriately enrolled basing their eligibility on serologically defined HLA-typing.

Total rectal resection, mesorectum excision, and coloendoanal anastomosis: a therapeutic option for the treatment of low rectal cancer

BACKGROUND

There is recent and sporadic evidence indicating that patients with very low rectal cancer may be treated via a sphincter-saving procedure, obviating the need for abdominoperineal resection and definitive colostomy. This study confirms these findings.

METHODS

From March 1990 to October 1994, 79 patients affected with primary low rectal cancers were submitted for total rectal resection, mesorectum excision, and coloendoanal anastomosis. All lesions were located within 8 cm of the anal verge (within 6 cm in 64 cases).

RESULTS

Eight patients relapsed at the pelvic level, and one patient only at the paraanastomotic site. Postoperative morbidity attributable to the procedure was low. A perfect continence was documented in 66% of cases after colostomy closure, and many patients (63%) had one or two bowel movements a day. Sixty-two patients of this series are alive, 49 without actual evidence of disease. Follow-up ranged from 2 to 56 months (median 23).

CONCLUSIONS

The clinical and pathological data derived from this study suggest that radical mesorectum excision more than a large clearance margin of resection remains the most important factor in reducing the incidence of local relapse after low rectal cancer surgery and that total rectal resection and coloendoanal anastomosis is a suitable and safe option to traditional, demolitive surgical techniques.

Manual dissection of adenocarcinoma of the lower third of the rectum specimens for detection of lymph node metastases smaller than 5 mm

BACKGROUND

The question of whether manual dissection when searching for metastatic lymph nodes from rectal cancer (less than 5 mm) is a reliable method remains controversial.

METHODS

We examined 50 consecutive cases of primary adenocarcinoma of the rectum treated with a sphincter-sparing total rectum resection, total mesorectum excision, and coloanal anastomosis. We used a manual method for the detection of lymph nodes.

RESULTS

One thousand seven hundred ninety-three lymph nodes were found (mean, 36 per patient). One hundred seventy-four contained metastases. Seventy-nine (45.4%) of the affected lymph nodes were less than 5 mm in greatest dimension. The percentage of metastases to small lymph nodes was similar to the percentage reported by Kotanagi (50%), but lower than the report of Herrera (78%), who used a clearing technique to search for regional lymph nodes.

CONCLUSIONS

A median 17 months follow-up in these patients demonstrated that metastases in small lymph nodes are important in the accurate staging of rectal tumors and that a manual method of searching for small lymph nodes is reliable.

Biological activity and clinical efficacy of intravenous high-dose thymopentin in metastatic melanoma patients

Eight patients with cutaneous metastatic melanoma were submitted to high-dose intravenous thymopentin (TP5) treatment for 5 weeks: three patients received 1 g three times a week, three received 1 g daily and two received 2 g daily. Four out of eight patients presented a partial response of cutaneous lesions lasting for 1-7 months, and six remain alive with evidence of disease after a follow-up of 2-7 months. A remarkable histologic observation is the presence of tumour necrosis, which was seen as both single cells and large confluent areas. The majority of lymphoid cells present in the tumour are CD45RO+ and CD4+. The CD4+ cells might play an important role in the anti-tumour immune local response by secreting cytokines and inducing apoptotic and necrotic cell death. This hypothesis seems to be confirmed by the presence of a high number of CD4+ cells around intratumoral vessels, while the presence of endovascular micro-thrombosis provides indirect evidence of cytokine activity. Cellular lysis may be produced by the activity of both CD8+ and CD4+ lymphoid cells. The role of TP5 may be an activation of CD4+ and CD8+ lymphoid cells. Clinical and pathological data indicate that TP5 is able to produce consistent clinical and immunological effects in melanoma patients with cutaneous metastases.

Cytokine-based gene therapy of human tumors. An overview

This review first summarizes the different strategies of gene therapy of cancer and then focuses on the immunological approach. Several studies in animal models with cytokine gene-transduced tumor cells indicate that local cytokine release usually results in tumor growth inhibition. Moreover, in a number of cases vaccination with such cells can reduce growth of established tumors or even cure the tumor-bearing animals. Translation of such a principle in human clinical setting is reported. We have transduced human melanoma cells with genes coding for interleukin (IL)-2, IL-4 or B7-1 and characterized such lines. The phenotype did not change after gene insertion but the functional, immunostimulatory activity of IL-2 or B7-1 gene-transduced melanoma cells was significantly increased compared to that of parental lines. These-lines were then used to vaccinate melanoma patients. Preliminary results of trials with IL-2 gene-transduced cells are presented which indicate a weak clinical response and the activation of a melanoma-specific cytotoxic T lymphocyte response in a low percentage of patients.