INTRODUCTION Malignant pleural effusion (MPE) is one of the commonest causes of pleural effusion in Myanmar. The diagnosis of MPE can be sometimes difficult to make because of the inconclusive result of pleural biopsy report. We studied the clinical features of MPEs as well as diagnostic procedures.
OBJECTIVE Our research goal and the objective of the study are to review the natural history of patients with a malignant pleural effusion but without obvious evidence of a primary lesion and to assess the value of diagnostic investigations to confirm the malignant pleural effusion. To follow the objectives, we collect the information on the disease characteristics such as age, gender, clinical features, nature and microscopic examination of pleural fluid, positivity rate of blind pleural biopsy results in patients diagnosed with bronchogenic carcinoma in the Chest Medical Department in Yangon General Hospital, Myanmar.
METHODS This study was a hospital based descriptive cross sectional study, performed at Chest Medical Department, Yangon General Hospital, Myanmar, from January 2004 through January 2005. Thorough history taking and physical examinations, radiological findings, hematological and serum biochemical profiles were recorded. Pleural aspiration and biopsy were also performed.
RESULTS 43 males and 30 females presenting with malignant pleural effusion were included in this study. The commonest age group lies between 61 to 70 years old with mean ± SD age of 63.45. 60 patients (82.2%) of malignant pleural effusions are heavy smokers or ex-smokers. 65 patients (88.9%) were diagnosed by identification of malignant pleural tissue in blind pleural biopsy, 8 patients (11.1%) were diagnosed by identification of malignant cells in the pleural fluid cytology because biopsies revealed chronic nonspecific pleuritis. Among histologically identified cell types most patients (33) had metastatic large cell carcinoma. Pleural fluid cytology for malignant cells was positive in 47 patients (64.4%). Common symptoms of malignant pleural effusions were breathlessness, cough, chest pain, weight loss and loss of appetite. Common physical signs were cachexia, fever on admission, palpable lymph node. Clinical features of consolidation and collapse were also noted in chest examinations. 45 patients had left sided effusion (61.6%) and 28 had right sided (38.4%). 47.9 % of pleural aspirate were blood stained. Mean ADA activity (SD) in malignant pleural effusion was 23.83 U/L. Mean protein concentration was 41.02 g/l, mean pleural fluid serum protein ratio was 0.61, LDH was 599.56 U/L, mean pleural fluid / serum LDH ratio was 1.18. Mean total and differential white cell counts of peripheral blood were within normal limits. Mean ESR was 62.23.
CONCLUSION Pleural fluid biochemical analysis can have an important contribution for investigation of patients with pleural effusion. The Light’s criteria is fulfilled in all cases of MPEs. Repeated pleural biopsy procedures will be necessary if first session failed to fetch the definitive tissue diagnosis. Pleuroscopy is recommended procedure for tissue diagnosis in MPEs.