Malignant pleural mesothelioma with heterologous elements.

AIMS: Malignant pleural mesothelioma with heterologous elements (such as osseous, cartilaginous or rhabdomyoblastic differentiation) is very rare. We tried to differentiate such mesothelioma cases from extraskeletal pleural osteosarcoma, which is very challenging. METHODS: We compared 10 malignant pleural mesotheliomas (three biphasic and seven sarcomatoid types) with two pleural osteosarcomas using clinicopathological and immunohistochemical methods, and also fluorescence in situ hybridisation (FISH) to examine for homozygous deletion of p16. RESULTS: The median age was 72 years for mesotheliomas, and 69 years for osteosarcoma. For mesothelioma, eight cases were male and two were female. Growth was diffuse in all mesothelioma cases except case 10, where it was localised, as it was for the two osteosarcomas. Among mesothelioma cases, 80% displayed osteosarcomatous and 60% chondromatous elements, while 10% exhibited rhabdomyoblastic ones. Immunohistochemical labelling for calretinin and AE1/AE3 was present in 8/10 and 7/10 mesotheliomas, respectively, but in only one osteosarcoma. Loss of methylthioadenosine phosphorylase was seen in 5/7 mesotheliomas. FISH analysis revealed homozygous deletion of p16 in 5/8 mesothelioma and 2/2 osteosarcoma. Median survival was 6.5 months after biopsy or surgical operation in mesothelioma, and 12 months after operation in osteosarcoma. CONCLUSIONS: Although median survival was longer for osteosarcoma than for malignant mesothelioma, we could not differentiate mesothelioma from pleural osteosarcoma on the combined basis of clinicopathological and immunohistochemical data, and FISH analysis. However, diffuse growth was more frequent in mesothelioma than in osteosarcoma.

Photodynamic therapy for pulmonary mucoepidermoid carcinoma.

Pulmonary mucoepidermoid carcinoma (PMEC) are rare, accounting for 0.1-0.2% of all malignant lung tumors. Furthermore, endobronchial lesions are rare and are more commonly found in the segmental or lobar bronchi. We present, to the best of our knowledge, the first case of successful treatment with photodynamic therapy (PDT) for PMEC. A 77-year-old male presented with cough and hemosputum for 4 months. Chest computed tomography showed a mass in the right intermediate bronchus. Endobronchial biopsy revealed a diagnosis of PMEC. An optimal surgical technique to preserve respiratory function was desirable as most of the tumor emerged from the bronchial glands in the central airways and was of low-grade type. Hence, PDT was performed. Repeat bronchoscopies were performed 5 years after the PDT and showed no evidence of tumor recurrence. PDT is more likely to be effective for low-grade PMECs that are visible on bronchoscopy.

Clinicopathological characteristics and treatment strategies for young lung cancer patients.

BACKGROUND: The reported age-specific survival rates of lung cancer patients have been largely inconsistent. Management strategies for younger patients and treatment outcomes are not well characterized. METHODS: Out of the 4,697 lung cancer patients with treatment history at Tokyo Medical University Hospital between January 2000 and December 2014, 266 patients were <49 years of age. Patient characteristics were investigated, and the association of overall survival (OS) with age, sex, stage, and histological type were investigated. RESULTS: The 1-, 3-, and 5-year survival rates in the ≤49 years age group were 82.9%, 64.6%, and 57.0%. Among surgical cases, the survival rate of patients in the ≤49 years age group was significantly better than that in the 50-69 and ≥70 years age groups (P=0.29 and P<0.0001, respectively). In comparison with the OS rate with clinical stages, I, II, and III (but not with clinical stage IV) in the older than 50 years age group, the rates in the ≤49 years age group were better. The 1-, 3-, and 5-year OS rates of females were higher than those of their males. The 1-, 3-, and 5-year OS rates for lung adenocarcinoma patients were higher than that of lung non-adenocarcinoma patients. CONCLUSIONS: Despite the higher proportion of advanced disease, the postoperative survival rate of the younger was higher than that of the older. Aggressive multimodality treatments, including surgery, are more feasible and effective for younger patients as compared with that in older patients.

[Bronchial Typical Carcinoid Requiring Left Upper Sleeve Lobectomy after Rigid Bronchoscopic Intervention].

A 17-year-old girl was referred to our hospital with atelectasis of left lung due to tumor occlusion. Clearance of the tumor was performed by mechanical removal and application of Nd-YAG laser or electrocautery. The histopathological diagnosis was typical carcinoid. Chest computed tomography showed extraluminal residual lesions. Left upper lung sleeve lobectomy was performed 1 year after initial treatment. Interestingly, the histology of the resected specimen showed that the tumor cells exist only on the outer side of the bronchial cartilage and not in the bronchial luminal surface, suggesting the effectiveness of the initial bronchoscopic treatment.

Effectiveness of Polyglycolic Acid Sheet Covering and Platelet-Rich Plasma after Video-Assisted Thoracic Surgery for Spontaneous Pneumothorax.

Background Video-assisted thoracic surgery (VATS) is widely used for the treatment of spontaneous pneumothorax, and the recurrence rate is high. The goal of the study was to examine the use of polyglycolic acid (PGA) sheets, together with platelet-rich plasma (PRP) from autologous blood for the prevention of postoperative recurrence of spontaneous pneumothorax. Materials and Methods We performed a retrospective study of 65 patients who underwent VATS for spontaneous pneumothorax from March 2008 to November 2011. The patients were divided into groups: without reinforcement (Group A, n = 33) and with reinforcement of the visceral pleura around the staple lines with the PGA sheet and PRP (Group B, n = 32). The postoperative follow-up period was 18 months. Results Chest tubes were used for 3.4 and 3.1 days in Groups A and B, respectively, with no significant difference between the groups. However, the recurrence rate (18.2%; 6 cases) in Group A was significantly higher than that in Group B (p = 0.02). The recurrence rates in patients younger than 25 years in Group A and Group B were 26.1 and 0.0%, respectively (p = 0.03). In Group A, the mean age with recurrence (18.3 years old) was significantly lower than the mean age without recurrence (p = 0.03). Conclusion These results suggest that the use of PGA sheets and PRP might be effective for the prevention of postoperative recurrence of spontaneous pneumothorax.

Photodynamic Therapy (PDT) with Chemotherapy for Advanced Lung Cancer with Airway Stenosis.

Intractable advanced lung cancer can be treated palliatively with photodynamic therapy (PDT) combined with chemotherapy to remove central and peripheral (lobar or segmental bronchi) bronchial stenosis and obstruction. We present data for 12 (eight men, four women) consecutive patients with 13 advanced non-small cell lung carcinomas in whom curative operations were contraindicated, who underwent PDT combined with chemotherapy for local control of the intraluminal lesions. The mean age was 73.3 years (range, 58-80 years), and the stages of cancer were IIA-IV. The median stenosis rates before treatment, one week post-treatment, and one month post-treatment were 60% (range, 30%-100%), 15% (range, 15%-99%), and 15% (range 15%-60%), respectively. The mean and median survival times were 9.3 and 5.9 months, respectively. The overall 1-year survival rate was 30.0%. No PDT-related morbidity or mortality occurred. In this single-institution study, all patients experienced improved symptoms and quality of life at one week after treatment; furthermore, an objective response was evidenced by the substantial increase in the openings of the bronchial lumen and prevention of obstructive pneumonia. Therefore, PDT with chemotherapy was useful and safe for the treatment of bronchial obstruction.

Management of thyroid carcinoma showing thymus-like differentiation (CASTLE) invading the trachea.

PURPOSE: To define the clinicopathological features and discuss the optimal management of carcinoma showing thymus-like differentiation (CASTLE). METHODS: We retrospectively analyzed six patients with CASTLE. RESULTS: The subjects comprised two men and four women (average age at initial diagnosis, 61 years, range 47-75 years). Preoperative biopsy yielded a correct diagnosis in two patients. Five patients underwent surgery and one was treated with radiation therapy alone. Four had extrathyroidal invasion and three had lymph node metastasis. During the clinical course, tracheal invasion was detected in five patients, the upper extent of the tumor being the lower half of the first tracheal ring. Two of these patients underwent tracheal sleeve resection. Two patients received postoperative radiotherapy for nodal metastasis, and one, after palliative surgery. The median follow-up period was 67 months (range 38-129). Recurrence was found 10 years post-therapy in the patient treated with radiation therapy only, resulting in death soon after. Although local recurrence was not found in the remaining five patients, new pulmonary metastases were diagnosed in the patient who underwent non-curative surgery. CONCLUSIONS: CASTLE can be diagnosed preoperatively by core needle biopsy and CD5 staining. Curative resection with neck dissection followed by radiotherapy can yield a good outcome. Larynx-sparing complete resection may be more feasible for CASTLE, even though it has a higher incidence of tracheal invasion than differentiated thyroid carcinoma.

Clinical response of large cell neuroendocrine carcinoma of the lung to perioperative adjuvant chemotherapy.

Patients with large cell neuroendocrine carcinoma (LCNEC) of the lung are considered to have poor prognosis. However, the benefit of adjuvant chemotherapy for these patients has not been established. In this study, we retrospectively evaluated the efficacy of perioperative chemotherapy for patients with completely resected LCNEC in a single-center setting. From 1999 through 2007, 45 patients with surgically resected LCNEC or mixed LCNEC containing at least one portion of the neuroendocrine differentiation or morphology in non-small cell lung carcinoma were enrolled as participants of this study. Survival rates were calculated by the Kaplan-Meier method. Differences between survival curves were computed with the log-rank test. For multivariate analysis, the Cox's proportional hazards regression model was used to evaluate variables that were significant predictors of survival. Of 1397 patients undergoing surgical resection for primary lung cancer from 1999 to 2007, 45 (3.2%) were classified as LCNEC. Thirty-six (80%) patients were men, and nine (20%) were women. Twenty-four (92%) of 26 patients were present or past smokers. Twenty-three (41%) of 45 patients received perioperative chemotherapy, including seven induction chemotherapies and 16 adjuvant chemotherapies. Survival of patients who underwent perioperative adjuvant chemotherapy was significantly higher than that of those who received surgery alone (P = 0.04). The 5-year survival rate of patients who underwent perioperative adjuvant chemotherapy was 87.5%, whereas that of patients who underwent surgery alone was 58.5%. Even in stage I cases, perioperative adjuvant chemotherapy still favors survival compared with surgery alone. In the Cox proportional hazard multivariate analysis, surgery with or without chemotherapy showed an independent prognostic influence on overall survival (P = 0.0457). Patients who received surgery alone were 9.5 times more likely to die than patients who underwent surgery plus chemotherapy. In conclusion, perioperative chemotherapy will be needed to improve survival in patients with LCNEC. As the population of LCNEC is small, it has been difficult to conduct randomized controlled trials to show the survival benefit of adjuvant chemotherapy. This should be, therefore, evaluated further in prospective multi-institutional phase II trials.

The prognostic impact of main bronchial lymph node involvement in non-small cell lung carcinoma: suggestions for a modification of the staging system.

BACKGROUND: The therapeutic strategies for non-small cell lung carcinoma (NSCLC) with N1 and N2 disease differ remarkably. Debate exists about the definition of the borderline between N1 and N2 stations. This study evaluated the prognostic effect of N1 disease, especially focused on the significance of the main bronchial node (No. 10) vs N2 disease. METHODS: The records of 1601 patients who underwent complete pulmonary resection for NSCLC were reviewed to examine the clinical features of lymph nodal involvement. RESULTS: There were 1086 patients (67.8%) with pN0 disease, 202 (12.6%) with pN1, and 274 (17.1%) with pN2 disease; overall 5-year survival rates were 74.7%, 56.1% and 28.9%, respectively (p < 0.001). Overall 5-year survival rates were 60.2% in hilar N1 and 49.6% in intralobar N1. Overall 5-year survival rates were 58.6% in N1 without node 10 and 35.1% in N1 with node 10. A significant difference was observed between N0 and N1 without node 10 (p < 0.001), and N1 without node 10 and N1 with node 10 (p = 0.033); however, the difference between N1 with node 10 and N2 was not significant. The status of node 10 involvement was an independent prognostic factor of pN1 patients, as well as age and gender. CONCLUSIONS: Patients with node 10-positive N1 disease have an unfavorable prognosis, and the disease behaves like N2 disease. The definition of clear borderline between N1 and N2 is mandatory to achieve a uniform classification map. This study offers further information for clinical and therapeutic purposes.

Quantitative p16 and ESR1 methylation in the peripheral blood of patients with non-small cell lung cancer.

Inactivation of the p16 and ESR1 tumor suppressor genes by promoter lesion methylation has been reported in many tumor types, including lung cancer. We examined the blood of 95 non-small cell lung cancer patients (66 cases of adenocarcinoma, 23 of squamous cell carcinoma and 6 of large cell carcinoma) and 30 controls consisting of normal subjects and benign disease patients to determine the methylation ratios of p16 and ESR1 using real-time PCR. For both genes, there was a statistically significant difference in the methylation ratio between non-small cell lung cancer patients and controls (p16; p<0.01, ESR1; p<0.001). In addition, there was a strong correlation between the methylation ratio of each gene and old age (p16; p<0.01, ESR1; p<0.001 and p16 or ESR1; p<0.001), and between p16 or ESR1 methylation rate and smoking history (p<0.01). Moreover in Stage I cases, the methylation positive rate of each gene (p16, ESR1 and p16 or ESR1) was higher than the CEA positive rate (p<0.05, p<0.001, p<0.001). Evaluation of p16 and ESR1 promoter methylation in blood using real-time PCR appears to be very useful for lung cancer diagnosis and there is some possibility that these methylated genes might come to represent useful biomarkers for the early detection of lung cancer. Our study results also suggested that comparative evaluation of the methylation ratio before and after surgery might be a powerful tool to predict the prognosis of lung cancer patients.

Endoscopic tumor ablation for laryngotracheal intraluminal invasion secondary to advanced thyroid cancer.

CONCLUSIONS: Endoscopic tumor ablation is a valuable option for inoperable postoperative laryngotracheal intraluminal invasion of well-differentiated thyroid carcinoma (DTC). OBJECTIVES: To investigate whether DTC invasion to the laryngotracheal mucosa can be controlled by 'simple' tumor ablation considering its relatively slow-growing nature. PATIENTS AND METHODS: Twenty-two consecutive patients underwent endoscopic tumor ablation caused by DTC for local control of intraluminal lesions with no significant extrinsic laryngotracheal compression in symptomatic or asymptomatic patients in whom radical operations were contraindicated. Debulking by Nd:YAG laser was followed by electrocoagulation and microwave coagulation for the residual tumor base. RESULTS: The critical complication, post-treatment supraglottic stenosis, was managed by prophylactic minitracheotomy. During the follow-up period of up to 125 months, 6 of 22 patients died (median survival 50 months), mainly of lung metastases, but all had a patent airway at death. Post-surgical extraluminal lesion growth is indolent and since relapse of the intraluminal lesion is the main cause of symptoms, satisfactory local control could be obtained by re-ablation of the mucosal lesion every few years. Lesions requiring retreatment within 1 year after initial treatment usually have high-grade malignancy, causing extrinsic compression, and prognosis is unfavorable.

Airway stenting for the treatment of laryngotracheal stenosis secondary to thyroid cancer.

BACKGROUND AND OBJECTIVE: Airway stenting can be a valuable therapeutic option for symptomatic airway stenosis, but its role in the palliation of advanced thyroid cancers invading the upper airway is unclear. This study examined the hypothesis that durable and replaceable silicone stents would give better results than self-expanding metallic stents. METHODS: A retrospective analysis was conducted of consecutive patients stented for laryngotracheal obstruction due to thyroid cancer. Stenting was performed via a rigid bronchoscope when airway patency after dilatation was

The present status of postoperative adjuvant chemotherapy for completely resected non-small cell lung cancer.

Non-small cell lung cancer (NSCLC) constitutes approximately 85% of all lung cancers, with patients having a poor prognosis. Approximately one third of NSCLC patients present with early-stage disease in which potentially curative resection and multi-modality therapy. Although adjuvant chemotherapy is the standard practice for patients with stages I-III breast and colorectal cancer, the therapeutic efficacy of adjuvant chemotherapy, following complete surgical resection of early stage NSCLC, has not been fully established. Several prospective randomized trials for patients with early stage NSCLC (stages I-IIIA) have confirmed a survival benefit with cisplatin-based adjuvant chemotherapy, as demonstrated in the 1995 meta-analysis performed by the NSCLC Collaborative Group. Studies from Japan have reported that adjuvant therapy with uracil-tegaful (UFT) afforded an improvement of 4% in the 5-year survival rate and a relative risk reduction of 26% in mortality at 5 years among patients with T1-2N0 (stage I) disease. In particular, the Japan Lung Cancer Research Group has demonstrated an improvement in the 5-year survival rate of 11%, favoring chemotherapy with UFT in the subset of patients with T2N0 (stage IB) disease. Two published meta-analyses based on abstracts have estimated a relative risk reduction in mortality of 11-13% at 5 years. The Lung Adjuvant Cisplatin Evaluation (LACE), which was based on a pooled analysis of five randomized trials, has demonstrated that cisplatin-based adjuvant chemotherapy improved survival in patients with completely resected NSCLC. This benefit depended on stage, being greatest in patients with stage II or IIIA disease. This analysis has suggested that platinum-based adjuvant chemotherapy may have no benefit for patients with stage IA and only a marginal benefit for patients with stage IB. Thus, the information available at the current time supports the administration of adjuvant chemotherapy for patients who have undergone complete resection of stages IB-IIIA NSCLC. Further research is needed to define the role of adjuvant platinum-based chemotherapy and its use, in conjunction with chest radiotherapy as the treatment for patients with resected stages IB and IIIA NSCLC.

Met-RANTES ameliorates fibrous airway obliteration and decreases ERK expression in a murine model of bronchiolitis obliterans.

OBJECTIVES: Bronchiolitis obliterans (BO) is the main cause of late mortality among long-term survivors of lung transplantation. Chemokine-chemokine receptor (CCR) interaction and subsequent recruitment of infiltrating cells to the graft are early events in the development of chronic rejection of transplanted lungs. The present study investigated whether blockade of chemokine receptors CCR1 and CCR5 with Met-regulated-on-activation, normal T cells expressed and secreted (RANTES), an amino-terminal modified derivative of RANTES/CCL5, affects the development of BO in murine model and we sought to determine the expression of RANTES/CCL5 and their relationship with extracellular signal-regulated kinase (ERK). MATERIALS AND METHODS: BALB/c mouse tracheas were heterotopically transplanted into C57Black6 recipients and treated for 21 days with either Met-RANTES at 20 microg/day or vehicle. Animals were killed at 21 days after transplantation for histologic examination of ERK expression. RESULTS: RANTES/CCL5 was highly expressed in allografts compare to isografts. Met-RANTES treatment ameliorated fibrous airway obliteration in a mouse model of BO and decreased ERK expression. CONCLUSION: Blockade of chemokine receptors by Met-RANTES ameliorated airway obliteration and decreased ERK expression. These findings suggest that chemokine receptors CCR1 and CCR5 play significant roles in the development of chronic rejection and ERK may be a new molecular target for chronic rejection.

Hypereosinophilia in a patient with invasive thymoma with clonal T-lymphocyte expansion expressing CD4, CD8, and CD25 antigens.

We report the case of a patient with hypereosinophilia and invasive thymoma harboring probable clonal proliferation of CD4+, CD8+, and CD25+ T-lymphocytes. A 64-year-old woman had eosinophilia (14.1 x 10(9)/L) and an anterior mediastinal tumor with elevated levels of serum immunoglobulin E (609.8 mg/dL) and interleukin 5 (239 pg/mL). Bone marrow aspirate showed marked infiltration by morphologically normal eosinophils with a normal karyotype but no FIP1L1-PDGFRA fusion gene. Flow cytometric analysis revealed an increasing number of CD3+/CD25+ lymphocytes in the peripheral blood, and the resected thymoma had infiltrated lymphocytes with CD4/CD8/CD25 antigens. Moreover, the thymoma had T-cell receptor rearrangements with a cytogenetically clonal nature, ie, t(2;4)(p22;q26). Although the number of patients with thymoma showing hypereosinophilia is small, this case suggests that a subset of patients with thymoma may have clonal expansion of T-lymphocytes with abnormal phenotypes that affect clinical manifestations, including hypereosinophilia.

Methylation of apoptosis related genes in the pathogenesis and prognosis of prostate cancer.

We investigated aberrant methylation in 101 prostate cancers(PCa) and 32 histologically normal prostate tissues. We focused on genes largely in the apoptotic pathway. Methylation frequencies of the genes were Reprimo, 54%; TMS1, 47%; DcR1, 45%; RRAD, 37%; DcR2, 37%; CRBP1, 34%; HPP1, 32%; RIZ1, 31%; DRM/Gremlin, 21%; SOCS1, 20%; DR4, 5%; DR5, 1%. Methylation of Reprimo and TMS1 correlate with preoperative serum prostate-specific antigen. Methylation of TMS1, DcR1, DcR2, and CRBP1 correlate with Gleason score. Methylation of TMS1 and unmethylation of both DcR1 and DcR2 correlate with poorer disease free survival by univariate and multivariate analyses. Our data suggest that methylation of multiple genes may be involved in pathogenesis and correlate with prognosis of PCa.

Cytokine responsiveness in cultured human small airway epithelial cells in relation to lung transplantation.

BACKGROUND: We report a new method for collecting and establishing small airway epithelial cells (SAEC). This method enables the evaluation of the cytokine responsiveness of SAEC, which is still unknown. In this study we evaluated intercellular adhesion molecule-1 (ICAM-1) expression on SAEC stimulated with several inflammatory cytokines and compared it with that on large airway epithelial cells (LAEC). MATERIALS AND METHODS: LAEC and SAEC were treated with IFN-gamma, TNF-alpha, IL-1beta, or their combination. ICAM-1 expression under various conditions was quantified by flow cytometry. Furthermore, immunocytochemical staining was performed to determine intranuclear displacement of signal transducer and activator transcription 1 (Stat1) during ICAM-1 expression by various cytokine stimulations. RESULTS: 1) ICAM-1 expression on both LAEC and SAEC was significantly increased by IFN-gamma stimulation alone and synergistically enhanced by IFN-gamma plus TNF-alpha or IL-1beta stimulation, 2) intranuclear displacement of Stat1 in SAEC by the stimulation with IFN-gamma plus TNF-alpha or IL-1beta was recognized earlier in comparison with that by IFN-gamma stimulation alone. CONCLUSION: The previously unknown peripheral cytokine responsiveness and its mechanisms of SAEC were revealed by this study, which contributes to the understanding of chronic lung allograft rejection recognized around small airways.

Aberrant methylation of HIN-1 (high in normal-1) is a frequent event in many human malignancies.

HIN-1 (high in normal-1) is a putative cytokine with growth inhibitory activities and is downregulated by aberrant methylation in breast cancers. We studied HIN-1 methylation status in many types of adult and pediatric malignancies and cell lines. We examined the expression of HIN-1 mRNA in 52 cell lines and the promoter methylation status in the cell lines and in over 800 primary tumors representing 17 tumor types using methylation specific PCR. Promoter methylation was observed in 73% of breast cancer, 67% of nonsmall cell lung cancer (NSCLC), 30% of small cell lung cancer (SCLC) and 57% of malignant mesothelioma (MM) cell lines, and methylation was completely correlated with loss of expression. Expression negative cell lines restored HIN-1 expression after treatment with 5-aza-2'-deoxycytidine. Promoter methylation of HIN-1 was found in 90% of retinoblastomas, 73% of Wilms' tumors, 61% of rhabdomyosarcomas, 57% of breast cancers, 52% of prostate cancers, 40% of MMs, 28% of NSCLCs and 27% of lymphomas. Methylation frequencies in colorectal cancers, cervical cancers, bronchial carcinoids, SCLCs, neuroblastomas, osteosarcomas, leukemia, medulloblastomas and bladder cancers were lower (4-21%), while hepatoblastomas lacked methylation. HIN-1 methylation was rarely detected in nonmalignant tissues (8 of 165, 5%). Aberrant methylation of HIN-1 with loss of expression is a common event and may contribute to the pathogenesis of many types of human malignancies.

Aberrant methylation profile of human malignant mesotheliomas and its relationship to SV40 infection.

Malignant mesothelioma (MM) is associated with asbestos exposure and the presence of SV40 viral sequences. Recently, we reported that SV40 infection of human mesothelial cells (HM) causes aberrant methylation of the tumor suppressor gene (TSG) RASSF1A. We investigated methylation of 12 genes by methylation-specific PCR in 63 MMs, six MM cell lines, and two foci of SV40-infected HM. Methylation percentages of the tested genes ranged from 3 to 65%. The frequencies of HPP1, RASSF1A, Cyclin D2, and RRAD methylation, and the value of the methylation index, were significantly higher in SV40 sequence-positive MMs than in SV40-negative MMs. Methylation of TMS1 and HIC-1 was associated with shortened survival. SV40-infected HM showed progressive aberrant methylation of seven genes (RASSF1A, HPP1, DcR1, TMS1, CRBP1, HIC-1, and RRAD) during serial passage. Our results demonstrate a relationship between SV40 and methylation of multiple genes in MM, indicating that the virus plays a role in the pathogenesis of MM.