Masafumi Kawamura

Expression profiles of non-small cell lung cancers on cDNA microarrays: Identification of genes for prediction of lymph-node metastasis and sensitivity to anti-cancer drugs

To investigate genes involved in pulmonary carcinogenesis and those related to sensitivity of nonsmall cell lung cancers (NSCLCs) to therapeutic drugs, we performed cDNA microarray analysis of 37 NSCLCs after laser-capture microdissection of cancer cells from primary tumors. A clustering algorithm applied to the expression data easily distinguished two major histological types of non-small cell lung cancer, adenocarcinoma and squamous cell carcinoma. Subsequent analysis of the 18 adenocarcinomas identified 40 genes whose expression levels could separate cases with lymph-node metastasis from those without metastasis. In addition, we compared the expression data with measurements of the sensitivity of surgically dissected NSCLC specimens to six anti-cancer drugs (docetaxel, paclitaxel, irinotecan, cisplatin, gemcitabine, and vinorelbine), as measured by the CD-DST (collagen gel droplet embedded culture-drug sensitivity test) method. We found significant associations between expression levels of dozens of genes and chemosensitivity of NSCLCs. Our results provide valuable information for eventually identifying predictive markers and novel therapeutic target molecules for this type of cancer.

Surgical treatment for both pulmonary and hepatic metastases from colorectal cancer

OBJECTIVE The role of surgery in the treatment of patients with pulmonary and hepatic metastases from colorectal cancer has not been delineated. METHODS Of the 351 patients enrolled in the Metastatic Lung Tumor Study Group of Japan between June 1988 and June 1996 who underwent thoracotomy for pulmonary metastases from colorectal cancer, 47 also underwent hepatic resection for metastatic tumors. The records of these patients were studied. RESULTS The 47 patients who underwent pulmonary and hepatic resection had a 3-year survival of 36% +/- 8%, a 5-year survival of 31% +/- 8%, and an 8-year survival of 23% +/- 9%. The longest survival was 98 months. This patient was alive without recurrence. There was a significant difference in the cumulative survival of the patients with a solitary pulmonary metastasis and the patients with multiple pulmonary metastases (P =.04). Neither age, sex, location of the primary tumor, maximum diameter of the pulmonary metastases, method of pulmonary resection, number of hepatic metastases, nor method of hepatic resection was correlated with survival. However, 9 of 10 patients who survived 3 years or more after the initial thoracotomy had only one or two hepatic metastases. CONCLUSION Surgical treatment of a solitary pulmonary metastasis concurrent with or after resection of hepatic metastases from colorectal cancer may be appropriate if the hepatic metastases are resectable for cure. Patients with a solitary pulmonary metastasis and a small number of hepatic metastases are good candidates for resection. Long-term survival can be expected.

Frequency of transmission of human parvovirus B19 infection by fibrin sealant used during thoracic surgery

BACKGROUND Fibrin sealant is used in many kinds of surgical procedures. Although pasteurization is insufficient to remove human parvovirus (HPV) B19 from this plasma-derived product, the frequency of HPV B19 infection transmitted by its use has never been known. METHODS Blood samples of 85 patients more than 20 years of age who had undergone pulmonary resection with fibrin sealant were obtained before and 12, 24, and 48 weeks after surgery. Anti-HPV B19 antibody IgG (HPV B19 IgG) and HPV B19 DNA were detected with these samples. RESULTS In 56 (65.9%) of 85 patients, blood samples obtained before operation were positive for HPV B19 IgG. In these 56 patients, blood samples obtained 12 to 48 weeks after surgery were all negative for HPV B19 DNA by polymerase chain reaction (PCR). In 6 (20.7%) of 29 patients whose blood samples were negative for HPV B19 IgG before surgery, blood samples obtained 12 to 48 weeks after surgery were positive for HPV B19 DNA by PCR and also positive for HPV B19 IgG. In 5 of these 6 patients reticulocyte counts decreased to less than 10 x 10(9)/l 12 to 20 days after surgery. CONCLUSIONS Epidemiologic evidence suggests that more than 20% uninfected persons were subsequently infected with HPV B19 by use of fibrin sealant during surgery.

Histopathological features and prognostic significance of the micropapillary pattern in lung adenocarcinoma

The micropapillary pattern is characterized by small papillary tufts with no fibrovascular core lying in spaces and has been reported as an aggressive variant of carcinoma in several organs. We investigated the histopathobiological properties of the micropapillary pattern with immunohistochemistry, serial sections, and electron microscopy in lung adenocarcinoma. We further analyzed its clinicopathological character and prognosis. The subjects included 383 adenocarcinoma cases, of which 184 (48%) were micropapillary pattern-positive and 199 (52%) were micropapillary pattern-negative. On histology, micropapillary tufts seemed to float in the alveolar space or spaces encased by connective tissues, whereas serial sections revealed that most tufts had continuity with other tufts and even with the main tumor. Positive staining for the adhesion molecules E-cadherin and β-catenin suggested the preservation of tight adhesion, and electron microscopy showed the existence of intercellular junctions. Negative staining for laminin and loss of basement membrane as determined by electron microscopy suggest a loss of cell–matrix contact. Positive staining for Ki-67 indicates that cells constituting micropapillary tufts retained their proliferation potency. There were no CD34-positive cells in micropapillary tufts, and the loss of the vascular core was confirmed. In micropapillary pattern-positive cases, lymphatic invasion was identified significantly more frequently than in micropapillary pattern-negative cases (P<0.001), even at stageIA (without lymph node metastasis, N=197) (P<0.001). The 5-year and 10-year overall survival rates of the micropapillary pattern-positive stageIA group were 77.6 and 67.6%, respectively, which were significantly less than those of the micropapillary pattern-negative stageIA group (98.1 and 98.1%) (P=0.001). In conclusion, cells constituting the micropapillary pattern are likely to have acquired anchorage-independent growth and a potential for high malignancy.

Pulmonary Metastasectomy for Pulmonary Metastases of Head and Neck Squamous Cell Carcinomas

BACKGROUND The lung is the major organ for distant metastasis from head and neck cancers, and pulmonary metastasectomy is indicated for selected cases. The efficacy of surgical treatment for pulmonary metastatic lesions from head and neck cancers has not been thoroughly examined. METHODS The database developed by the Metastatic Lung Tumor Study Group of Japan was retrospectively reviewed. Between November 1980 and September 2006, 237 patients underwent resection of pulmonary metastases from primary head and neck cancers. After excluding nonsquamous cell carcinomas, 114 cases were analyzed, and the survival and prognostic factors for pulmonary metastasectomy for metastases from head and neck cancers were determined. RESULTS The overall 5-year survival rate after pulmonary metastasectomy was 26.5%, and the median survival time was 26 months. As determined by univariate analysis, poor prognostic factors were oral cavity cancers, lymph node metastasis, a disease-free interval of 24 months or less, and incomplete resection. Multivariate analysis revealed that poor prognostic factors were being male, having oral cavity cancers, lymph node metastasis, and incomplete resection. When patients were divided into males with oral cavity cancers (n = 17) and all others (n = 97), the 5-year survival rates were 0% and 31.6%, respectively. Survival of male patients with oral cavity cancer that metastasized was significantly reduced (p < 0.001). CONCLUSIONS Male sex, oral cavity cancers, lymph node metastasis, and incomplete resection were poor prognostic factors for pulmonary metastases, but there is the potential for a good surgical outcome in carefully selected patients.

Percutaneous cryoablation of lung tumors: Feasibility and safety

PURPOSE To evaluate the safety and feasibility of cryoablation for lung tumors as well as the incidence of, and risk factors for, complications. MATERIALS AND METHODS This study included 193 cryoablation sessions for 396 lung tumors in 117 consecutive patients. Univariate and multivariate analyses were performed to assess risk factors for common complications. Changes in laboratory values were analyzed the day after cryoablation. RESULTS Pneumothorax, pleural effusion, and hemoptysis occurred after 119 (61.7%), 136 (70.5%), and 71 (36.8%) sessions, respectively. Phrenic nerve palsy, frostbite, and empyema occurred after one session each (0.52%). Proximal tumor implantation was observed in one of 471 punctures (0.20%). Of 119 sessions with pneumothorax, 21 (17.6%) required chest tube insertion and two (1.7%) required pleurodesis. Delayed and recurrent pneumothorax occurred in 15 of 193 sessions each (7.8%). A greater number of cryoprobes was a significant (P = .001) predictor of pneumothorax. Male sex (P = .047) and no history of ipsilateral surgery (P = .012) were predictors for the need for chest tube insertion, and no history of ipsilateral surgery (P = .021) was a predictor for delayed/recurrent pneumothorax. Greater number of cryoprobes (P = .001) and no history of ipsilateral surgery (P = .004) were predictors for pleural effusion. Greater number of cryoprobes (P < .001) and younger age (P = .034) were predictors for hemoptysis. Mean changes in white blood cell count, platelet count, hemoglobin level, and C-reactive protein level were 2,418/μL ± 2,260 (P < .001), -2.0 × 10(4)/μL ± 3.2 (P < .001), -0.77 mg/dL ± 0.89 (P < .001), and 3.0 mg/dL ± 2.9 (P < .001), respectively. CONCLUSIONS Percutaneous cryoablation could be performed minimally invasively with acceptable rates of complications.

Percutaneous cryoablation for the treatment of medically inoperable stage I non-small cell lung cancer.

Background To evaluate the midterm results of percutaneous cryoablation for medically inoperable stage I non-small cell lung cancer. Methodology/Principal Findings Between January 2004 and June 2010, 160 patients underwent computer tomography guided percutaneous cryoablation for lung tumors at our institution. Of these patients, histologically proven stage I lung cancer patients with more than one year of follow-up, were retrospectively reviewed. All of these patients were considered to be medically inoperable with Charlson comorbidity index of 3 or greater. Follow-up was based primarily on computed tomography. There were 22 patients with 34 tumors who underwent 25 sessions of cryoablation treatment. Complications were pneumothoraces in 7 treatments (28%, chest tube required in one treatment), and pleural effusions in 8 treatments (31%). The observation period ranged from 12–68 months, average 29±19 months, median 23 months. Local tumor progression was observed in one tumor (3%). Mean local tumor progression-free interval was 69±2 months. One patient died of lung cancer progression at 68 months. Two patients died of acute exacerbations of idiopathic pulmonary fibrosis which were not considered to be directly associated with cryoablation, at 12 and 18 months, respectively. The overall 2- and 3-year survivals were 88% and 88%, respectively. Mean overall survival was 62±4 months. Median overall survival was 68 months. The disease-free 2- and 3-year survivals were 78% and 67%, respectively. Mean disease-free survival was 46±6 months. Pulmonary function tests were done in 16 patients (18 treatments) before and after cryoablation. Percentage of predicted vital capacity, and percentage of predicted forced expiratory volume in 1 second, did not differ significantly before and after cryoablation (93±23 versus 90±21, and 70±11 versus 70±12, respectively). Conclusions/Significance Although further accumulation of data is necessary regarding efficacy, cryoablation may be a feasible option in medically inoperable stage I lung cancer patients.

Surgical outcomes for pulmonary metastases from hepatocellular carcinoma

BACKGROUND Although favourable prognosis following aggressive treatment of extrahepatic metastases from hepatocellular carcinoma (HCC) has been reported, surgical outcomes for pulmonary metastases are unclear. METHODS AND MATERIALS Sixty-one patients (2.6%) of 2297 registered with the Metastatic Lung Tumor Study Group of Japan between 1990 and 2006, who underwent surgery for pulmonary metastases from HCC, were retrospectively reviewed from the registry. RESULTS The overall 5-year survival rate was 32.2%. The prognosis was significantly better for < or =2 lesions than for > or =3 lesions (p=0.046), for < or =3 lesions than for > or =4 lesions (p=0.0070), and for < or =4 lesions than for > or =5 lesions (p=0.029). No other factors that influence outcomes were identified. A stepwise regression analysis showed three or less pulmonary metastases to be an independent factor for better prognosis (p=0.048). CONCLUSION With careful patient selection, comparatively good outcomes can be expected following surgical resection of pulmonary HCC metastases. Among them, patients with multiple metastases, if number of metastases is small such as four or less, can be expected to survive long after surgery.

An alternative method for screening EGFR mutation using RFLP in non-small cell lung cancer patients

Introduction: Epidermal growth factor receptor (EGFR) mutations are strong determinants of tumor response to EGFR tyrosine kinase inhibitors in non-small cell lung cancers (NSCLCs). Currently available methods of EGFR mutation detection rely on direct sequencing. Here, we describe the use of an alternative way to screen EGFR mutations. Methods: A total of 109 frozen tumor specimens from NSCLC patients were obtained. For mutational analysis of EGFR exons 18, 19, and 21, reverse transcription-polymerase chain reaction was performed on the cDNA using original primers designed for restriction fragment length polymorphism (RFLP). Results: EGFR mutations were detected in 37 patients (34%) by both RFLP and direct sequencing except one case in which it was detected only by RFLP. EGFR mutations were more frequently observed to be significant by multivariate analysis in patients with adenocarcinoma (OR = 5.56), no-smoking history (OR = 4.34), and 65-year-old or younger (OR = 2.64), but not in women (OR = 1.14). Among 37 patients, 18 were treated with gefitinib and 9 responded to the treatment. One patient without any mutation responded. Conclusion: RFLP is a useful method for screening EGFR mutations and can also be applied to predicting the sensitivity of NSCLC patients to EGFR-tyrosine kinase inhibitors.

Staple-line reinforcement with a new type of polyglycolic acid felt

Although various materials have been used for reinforcement in lung-volume-reduction surgery to buttress pulmonary staple-line, absorbable materials are not available for use in thoracoscopic surgery. Moreover, even nonabsorbable types of reinforcements have been used only for lung volume reduction surgery. However, elderly patients with spontaneous pneumothorax secondary to emphysematous lung are well treated with staple-line reinforcement. The authors developed a new type of polyglycolic acid felt to buttress staple-line. This felt is absorbable, easier to cut with a stapler knife than is the conventional polyglycolic acid felt, and inexpensive enough to use for various types of thoracic surgeries for emphysematous lungs in Japan, and it can be attached to staplers with a small amount of fibrin glue. These strips were used to reinforce pulmonary staple lines for resection of emphysematous lungs in 14 patients: pulmonary emphysema (n = 1), bilateral giant bullae (n = 1), ipsilateral giant bullae (n = 6), spontaneous pneumothorax with multiple bullae in an emphysematous lung (n = 5), and lung cancer in a patient with pulmonary emphysema (n = 1). There were no air leaks during surgery. Air leaks were noted in three patients after surgery. In two patients, the air leaks stopped within 2 weeks. In one patient, the air leak was found to originate from an untouched lobe during reoperation. No infection or allergic reaction developed in a patient during a mean follow-up of 12 months (range, 1 to 24 months).