Manabu Yasuda

Prospective phase II study of gefitinib in non-small cell lung cancer with epidermal growth factor receptor gene mutations.

BACKGROUND This study prospectively assessed the efficacy of gefitinib and the survival benefit for non-small cell lung cancer (NSCLC) patients with epidermal growth factor receptor (EGFR) mutations. METHOD Patients with either recurrent disease after undergoing surgery or advanced NSCLC disease (IIIB or IV) which demonstrated EGFR mutations were eligible for this study. EGFR mutations in exons 19-21 were examined. The patients with EGFR mutations were enrolled in this study after obtaining their informed consent a second time, and they were thereafter treated with gefitinib. RESULTS EGFR mutations were detected in 20 of 48 patients with NSCLC, and 19 patients were enrolled onto this study and treated with gefitinib. Seven patients had an exon 19 deletion, 10 had L858R, 1 had both, and 1 had an exon 19 deletion and G796A. The overall response rate was 63.2%, and the disease control rate was 89.5%. In patients with an exon 19 del and L858R, the response rates were 71.4% and 60.0%, respectively. The median progression-free survival time was 7.1 months, and the median survival time was 20.0 months. No life-threatening toxicity was observed. Four of five acquired resistant tumors showed an acquired T790M mutation. CONCLUSIONS EGFR mutations in exons 19 or 21 are considered to be a good predictor of the efficacy of gefitinib.

Survival and prognostic factors of surgically resected T4 non-small cell lung cancer

BACKGROUND Category T4 nonsmall cell lung cancer (NSCLC) encompasses heterogenous subgroups. We retrospectively analyzed the survival of patients with surgically resected T4 NSCLC to evaluate the evidence for prognostic implications according to the subgroups of T4 category, nodal status, and resection completeness. METHODS Seventy-six patients with T4N0-2M0 NSCLC were divided into three subgroups within the T4 category: 24 patients with the tumor invading the mediastinal organs (mediastinal group), 16 with a malignant pleural effusion or dissemination (pleural group), and 36 with satellite tumor nodules within the ipsilateral primary tumor lobe (satellite group). Complete resection was possible in 47 patients (61.8%). The pathologic N statuses were N0 in 28, N1 in 13, and N2 in 35 patients. RESULTS The overall survival of the 76 patients was 19.1% at 5 years. The overall 5-year survivals according to the three subgroups of the T4 category were as follows: mediastinal group, 18.2%; pleural group, 0%; and satellite group, 26.7% (mediastinal/satellite versus pleural, p = 0.037). Factors significantly influencing the overall 5-year survival were the pathologic N status (N2 versus N0-1, p = 0.022) and the completeness of resection (complete versus incomplete, p = 0.0001). A multivariate survival analysis demonstrated that the pathologic N status and the completeness of resection were significant independent predictors of a poorer prognosis even after adjusting for the subgroup of the T4 category. CONCLUSIONS Resectable T4N0-1 NSCLC that is not due to pleural disease deserves consideration of aggressive surgical resection with expected 5-year survival of about 20%.

A point mutation in the NFYC gene generates an antigenic peptide recognized by autologous cytolytic T lymphocytes on a human squamous cell lung carcinoma

We have identified an antigen recognized by cytolytic T lymphocytes (CTL) on the autologous tumor cells of a nonsmall cell lung cancer patient. The antigenic peptide, presented by HLA‐B*5201 molecules, was encoded by a mutated sequence in the gene coding for the C subunit of transcription factor NF‐Y. The mutation was present in the tumor sample from which the cell line was derived, and appeared to be unique to the tumor of this patient. In a lymph node draining the tumor, precursors of CTL recognizing the autologous tumor cells were detected at a frequency of about 1/30,000 of the CD8 cells, and 85% of them recognized the mutated NF‐YC peptide, suggesting that the patient mounted a T cell response against this antigen. These results strengthened the notion that unique tumor‐specific antigens are highly represented not only in melanoma but also in other types of tumors, like nonsmall cell lung cancer.

Clinical significance of cancer/testis antigens expression in patients with non-small cell lung cancer

Cancer/testis antigens (CT antigens) are thought to be suitable targets for antigen-specific immunotherapy, because of the cancer-specific expression except for the testis among various normal tissues and no-expression of HLA class I in the testis. In the present study, the expressions of CT antigens (MAGE-A3, MAGE-A4, NY-ESO-1 and KK-LC-1) in non-small cell lung cancer (NSCLC) were analyzed by RT-PCR. The subjects were 239 patients with NSCLC who underwent surgery from 2001 to 2005 in our department. The expression rates of MAGE-A3, MAGE-A4, NY-ESO-1 and KK-LC-1 were 23.8%, 20.1%, 10.5% and 32.6% in patients with NSCLC, respectively. MAGE-A4 was expressed more frequently in male (25.3%) than in female (10.6%) (p<0.01). The positive proportion of MAGE-A4 was higher in stages II-IV (30.6%) than in stage I (12.8%) (p<0.01). Both of MAGE-A3 and MAGE-A4 were expressed more frequently in squamous cell carcinoma than in adenocarcinoma (p<0.01). Such tendency was not observed among NY-ESO-1 and KK-LC-1 expression. KK-LC-1 was expressed in 32.1% of patients with adenocarcinoma and in 36.5% of patients with squamous cell carcinoma. Patients with positive MAGE-A4 expression showed significantly poorer overall survival than those without MAGE-A4 expression (p=0.013), and such effect on survival was also observed, when the analysis was limited to patients at stage I (p=0.0037). Expression of MAGE-A3, NY-ESO-1 or KK-LC-1 did not affect survival of patients with NSCLC significantly, however, expression of at least one of such CT antigens negatively affect survival of patients with NSCLC (p=0.045).

Simultaneous Cellular and Humoral Immune Response against Mutated p53 in a Patient with Lung Cancer

We recently identified several Ags recognized by tumor-infiltrating B lymphocyte-derived Ab using SCID mice and a xenografted non-small cell lung cancer system. One of these identified Ags was mutated p53 with a point mutation resulting in the alteration of codon 158 from Arg to Leu. The aim of this study was to ascertain whether cellular immunity against mutated p53 exists in the same patient together with humoral immunity. Two different nona peptides (mutated p53150 and p53155 peptides), including a mutated amino acid derived from p53, were synthesized according to the binding motif of HLA class I of the established cancer cell line A904L from the patient. Mediastinal lymph node lymphocytes of the patient were stimulated weekly with the peptides. The mutated p53155 peptide-stimulated lymphocytes showed specific cytotoxicity against both autologous EBV-transformed B cells pulsed with mutated p53155 peptide and A904L. The mutated p53155 peptide-specific CTL clone in an HLA-Cw*0702 restriction was established and analyzed for its TCR usage. Clonotypic PCR using CDR3-specific primers was applied to the tumor tissue containing the tumor-infiltrating lymphocytes. The specific amplification of PCR was found in the tumor tissue. These results demonstrated that not only B lymphocytes producing specific Ab against the p53 protein, but also CTL against mutated p53, expressed in autologous lung cancer cells exist in the tumor tissue. This approach may allow us to better understand the mechanisms of T and B cell immunity against the same tumor Ag in cancer patients.

Time Trends of Surgical Outcome in Patients with Non-small Cell Lung Cancer

Purpose: A surgical resection is a potentially curative treatment for non-small cell lung cancer (NSCLC). This study investigated the time trends of the surgical outcome in patients with NSCLC. Methods: This study clinicopathologically evaluated 1487 patients who had undergone a resection for NSCLC between 1979 and 2008 during the five periods of 1979–1988, 1989–1993, 1994–1998, 1999–2003, and 2004–2008. Results: The number of patients who underwent a resection during the five respective periods increased: 167, 261, 248, 382, and 429. The percentage of pathologic stage IA lung cancers was 16.2, 21.5, 23.0, 38.5, and 52.0% in each period, respectively, and it has risen rapidly in recent years. The percentage of adenocarcinoma has also progressively increased during each period: 49.1, 52.1, 54.7, 62.8, and 69.7%, respectively. The diameter of the tumors resected during each period was 36, 37, 38, 33, and 26 mm, respectively, showing that the tumor tended to be diagnosed at an increasingly smaller size. The postoperative 5-year survival rates during the five periods improved markedly: 34.1, 44.0, 44.9, 65.4, and 76.5%, respectively. Patients with pathologic stage IA lung cancer also exhibited increasingly higher 5-year survival rates during the five periods: 70.0, 71.2, 80.4, 89.2, and 88.7%, respectively. Conclusion: The prognosis of NSCLC patients has remarkably improved in recent years. The increase in the number of patients with adenocarcinoma in the early stage is thought to have strongly contributed to the favorable results. Thus, early diagnosis remains a key factor for improving the survival of lung cancer patients after surgical treatment.

Successful Induction of Tumor‐specific Cytotoxic T Lymphocytes from Patients with Non‐small Cell Lung Cancer Using CD80‐transfected Autologous Tumor Cells

Cytotoxic T lymphocytes (CTL) against human lung cancer cells are difficult to induce by a conventional method using tumor cell stimulation probably due to an insufficiency of tumor antigens (TA) or costimulatory molecules such as CD80. We, therefore, investigated the potential of CD80‐transfected tumor cells as stimulators of the in vitro induction of autologous tumor‐specific CTL from regional lymph node lymphocytes in patients with lung cancer. Five non‐small cell lung cancer cell lines (two adenocarcinomas, 1 squamous cell carcinoma, 1 large cell carcinoma and 1 adenosquamous cell carcinoma) were established from surgical specimens and were successfully transduced with a plasmid constructed with expression vector pBj and human CD80 cDNA, using a lipofection method. CD80‐transfected tumor cells (CD80‐AT) significantly augmented the proliferation of autologous lymphocytes from all cases as compared with non‐transfected tumor cells (AT). AT‐stimulated lymphocytes from 4 out of 5 cases did not show any cytotoxicity against AT; however, lymphocytes stimulated with CD80‐AT exhibited substantial cytotoxicity against parental AT in all 5 cases tested. AT‐stimulated lymphocytes derived from only one out of 5 cases showed major histocompatibility complex (MHC)‐class I‐restricted cytokine production in response to AT, while the MHC‐class I‐restricted responses were found in CD80‐AT‐stimulated lymphocytes from 4 out of 5 cases. These results indicate that CD80 on tumor cells could be a beneficial costimulatory molecule to elicit CTL against lung cancer, and also show that TA recognized by CTL was frequently expressed on lung cancer cells.

Significance of Smoking as a Postoperative Prognostic Factor in Patients with Non-small Cell Lung Cancer

Introduction: In this study, we investigated the influence of smoking on the postoperative prognosis in patients with non-small cell lung cancer. Methods: The subjects consisted of 770 patients who underwent a resection of lung cancer in our department between 1994 and 2005. We compared the clinico-pathological findings between the smoking and never-smoking groups. The pack-year index (PYI) was used as a smoking index. Results: The smoking group consisted of 569 patients (74%), and the never-smoking group consisted of 201 patients (26%). The smokers were composed of 492 men and 77 women. Among the adenocarcinoma patients, there were 293 (61%) smokers and 185 (39%) never-smokers. The patients with squamous cell carcinoma included 204 (95%) smokers and 10 (5%) never-smokers. The proportion of patients with stage IA disease was significantly higher in the never-smokers than that of the smokers. The 5-year survival rate after surgery was 66% in the never-smoking group; however, the rates were 56% in patients with a PYI more than or equal to 20, and 55% in those with PYI more than 20. Seventy-nine (13.9%) patients in the smoking group and seven (3.5%) patients in the never-smoking group died of other diseases, with a significant difference (p < 0.01). Of these patients, 44 (56%) and 13 (16%) in the smoking group died of respiratory and cardiovascular disorders, respectively. In our series, excluding those who died of other diseases, there were no significant differences in the postoperative prognosis. Conclusions: In the smoking group, the prognosis was poorer than that in the never-smoking group. The higher proportion of early stage disease (stage IA) and female gender were major causes of the better prognosis of the never-smokers. Nevertheless, the high pulmonary/cardiovascular complication-related mortality was another cause of the poor prognosis of the smokers with lung cancer.

Clinical significance of HLA class I alleles on postoperative prognosis of lung cancer patients in Japan.

BACKGROUND The role of the HLA phenotype in cancer prognosis has been frequently discussed. We previously reported the correlation between HLA alleles and the postoperative prognosis of 204 patients with non-small cell lung cancer (NSCLC). The present study was based on 695 patients with NSCLC to confirm these correlations. METHODS We evaluated the medical records of 695 NSCLC patients who underwent surgical resection. The serological typing of HLA class I was performed using a microcytotoxicity test of lymphocytes or PCR-sequence-specific oligonucleotides (PCR-SSO), and the correlation between the HLA alleles and the clinicopathological features was analyzed. The survival curves were calculated, and then a comparison of the survival curves was carried out. RESULTS The HLA-A2 positive(A2(+)) group at stage I showed a more unfavorable prognosis than HLA-A2(-) group in overall survival. At stage II+III, the HLA-A24(+) group had a poorer prognosis than the HLA-A24(-) group, and the HLA-B52(+) group showed unfavorable prognosis. Multivariate analysis demonstrated that HLA-A2 at stage I and HLA-A24 at stage II+III were the independent factors that affected the survival period. CONCLUSIONS The expression of HLA-A2 was considered as one of the unfavorable prognostic factors in the NSCLC patients at stage I. HLA-A24(+) group showed a significant unfavorable prognosis at stage II+III. These results suggested that HLA-A2 and HLA-A24 could be the prognostic factors in patients with NSCLC according to the state of advancement of the disease.

Gender Difference as a Prognostic Factor in Patients Undergoing Resection of Non-Small Cell Lung Cancer

PurposeWe studied the effects of gender difference on the incidence of lung cancer and its mortality rate, which is a subject of much discussion.MethodsWe examined gender difference in the clinical features of 491 men and 222 women who underwent resection of primary non-small cell lung cancer (NSCLC) between 1994 and 2004.ResultsThe histological types of cancer were adenocarcinoma in 249 (51%) of the men and 182 (82%) of the women, and squamous cell carcinoma in 182 (37%) of the men and 27 (12%) of the women. The incidence of adenocarcinoma was significantly higher in the women. The proportion of stage IA disease was significantly higher in the women than in the men (45% vs 29%, respectively). The 5-year overall survival rates were 50% in the men and 63% in the women. In a multivariate analysis, gender difference was an independent prognostic factor; however, when death as a result of unrelated disease was excluded, there was no significant difference in prognosis.ConclusionAlthough the higher incidences of adenocarcinoma and stage IA cancer contributed to the good results of surgery in women, the low incidence of death attributed to diseases other than lung cancer was a major reason for their better prognosis.