Masanori Kaneda

Rupture of a benign mediastinal teratoma into the right pleural cavity

A 27-year-old woman with a ruptured mediastinal cystic teratoma had high levels of amylase and carcinoembryonic antigen in cystic fluid. The activity of the amylase is thought to be the most likely cause of the rupture. High levels of carcinoembryonic antigen in pleural fluid are not necessarily indicative of a malignant lesion but may suggest the presence of a ruptured teratoma in patients with mediastinal tumors.

Immunohistochemical diagnosis of methylthioadenosine phosphorylase (MTAP) deficiency in non-small cell lung carcinoma

Methylthioadenosine phosphorylase (MTAP) is involved in the metabolism of purines and converts methylthioadenosine (MTA) to adenine. It is abundant in all normal tissues but is deficient in various tumors. Here, we investigated MTAP deficiency in clinical samples of lung cancer using immunohistochemistry (IHC), and compared these results with those obtained by real-time PCR. Seventy-five samples were obtained from patients who underwent operations for non-small cell lung cancer (NSCLC). MTAP genetic analysis, using real-time PCR, and IHC were carried out on the samples. Methylation-specific primers were used to analyze methylation of the MTAP promoter, using DNA treated with sodium bisulfite. Sixty-nine of 75 samples were compared using both IHC and real-time PCR. The IHC results were consistent with those of real-time PCR in 56 samples. Of 62 positive samples tested by real-time PCR, only 49 (79%) were MTAP-positive by IHC. Seven samples were MTAP-negative by real-time PCR and IHC. In 13 samples of PCR (+) and IHC (-), six samples showed that the promoter region of MTAP was methylated. IHC is an accurate and useful diagnostic method for detecting MTAP deficiency in NSCLC, and the frequency of MTAP deficiency was found to be relatively high. The metabolic alterations diagnosed by IHC could be exploited for selective chemotherapy.

The value of pleural lavage cytology examined during surgery for primary lung cancer

OBJECTIVES The pleural invasion (PL) score is a useful prognostic indicator in lung cancer. However, in many cases, the cancer may exfoliate itself into the pleural cavity and may progress to a malignant pleural effusion without invading the parietal pleura. This stage is not currently evaluated, but it is detectable by means of the pleural lavage cytology (PLC). However, PLCs contribution to TNM staging has not yet been clarified. The purpose of this investigation was to demonstrate the usefulness of PLC in the precise staging of patients with such an occult pleural dissemination. METHODS A total of 3231 patients who were included in a multi-institutional database were studied retrospectively. PLC was performed by washing the thoracic cavity with a small amount of physiological saline immediately after opening the thoracic cavity during lung cancer surgery. RESULTS The incidence of positive PLC findings was 4.58%. In comparison with the negative group, the survival curves were significantly worse (P < 0.001) and the incidence of recurrence with pleuritis carcinomatosa was significantly higher (P < 0.001). According to the subset analysis, the survival difference was prominent in earlier stage groups and lower PL score groups. The positive findings were confirmed to be a significantly poor prognostic indicator (P = 0.016) by multivariate analysis using the Cox proportional hazard model (Cox analysis). However, integration of the positive findings with the PL score was attempted for the convenience of TNM staging. To find the accurate PL score for positive PLC findings, the Cox analysis was re-estimated using the PL score upgraded stepwise. The most reliable model with the highest score for the likelihood ratio χ(2) statistic was obtained by scoring positive findings as PL3. So, it was considered to be the most reliable conversion. CONCLUSIONS Examining PLC in clinical practice is useful for detecting occult pleural dissemination before the appearance of a malignant pleural effusion. Evidence of positive findings should be treated as supplemental information to the precise diagnosis of TNM staging. Scoring positive PLC findings as PL3 (=T3) was appropriate.

Clinical features of primary lung cancer adjoining pulmonary bulla.

A few investigators have suggested a possible association between lung cancer and a pulmonary bulla. But its correlation is not yet fully understood. Five hundred and forty-five cases with primary lung cancer were studied retrospectively by re-evaluation of their chest computed tomography (CT)-scans. Cancer adjoined a bulla in 19 cases. In these instances, each cases clinical course, pathological findings and surgical results were investigated. All cases were men and were heavy smokers. Three of them were under 50 years of age. Bulla/cancer incidence was 3.5%. Initial symptoms were common respiratory symptoms in five cases (26.3%) and hemosputa and hoarseness in one case (5.3%), respectively. In comparison with the control group, a ratio of squamous cell carcinoma (SCC) and large cell carcinoma was significantly high (P<0.05) and differentiation of the carcinoma was poor (P<0.001). Although the pathological staging and lung function data revealed no statistical difference, the survival curve of bulla/cancer group was significantly worse (P<0.01). Primary lung cancer adjoining pulmonary bulla tends to be poor in prognosis, even if it was small in size. A low-density mass shadow adjoining the bulla should be frequently examined by CT-scans and should proceed to an exploratory thoracotomy if it have increased in size.

Surgical treatment for chronic lung and thoracic cavity infection

To avoid the complication of aspiration pneumonia, we attempted a new anterior approach of extrapleural pneumonectomy combined with thoracoplasty in four patients with chronic empyema, a bronchopleural fi stula, and severely destroyed lung. The thoracic cage was exposed by an L-shaped parasternal incision making a muscle-skin flap of the anterior chest. The anterior portions of ribs were removed at fi rst, and exfoliation was started in the mediastinal area. After detaching the lung from the mediastinum, an extrapleural pneumonectomy was completed. The backside ribs were then resected by way of the thoracic cavity. The muscle-skin flap was sutured to close the thoracic cavity completely. The procedure was tolerable for three cases. One patient died from accidental rupture of the descending aorta owing to atherosclerotic degeneration. Of the three successful outcomes, recurrence was observed in one case, although it was recurrence of malignant lymphoma associated with chronic empyema.