A fifty-two-year-old, nonsmoker female presented with right-sided severe dull aching chest pain, dry cough, and exertional dyspnoea for four months. Severity of chest pain was gradually increasing and disturbs her sleep at night. Shortness of breath was initially of mMRC grading 2; later it was increased to grade 3. There was no history of hemoptysis, fever, weight loss, and loss of appetite. There was no past history of pulmonary tuberculosis.
On examination, general survey revealed no abnormality. Her temperature was 97.2 F, pulse rate, 84 beats/minute, respiratory rate, 24 beats/minute, and blood pressure, 124/80 mmHg. Examination of respiratory system revealed diminished movement of chest wall on right side, tracheal shifting to left, apical impulse in left fifth intercostal space, 1.5 cm lateral to the left midclavicular line, stony dull percussion note over right chest wall, absent vesicular breath sound, and diminished vocal resonance on right side, suggestive of right-sided pleural effusion. Examination of other systems revealed no abnormality.
Complete hemogram and blood biochemistry (including serotonin, gastrin, somatostatin, and glucagon) were within normal limit. Chest X-ray posteroanterior view (CXR, PA view) revealed right-sided pleural effusion (Figure 1). Ultrasound of abdomen revealed no abnormality. Pleural fluid was aspirated from right hemithorax and its analysis showed haemorrhagic, exudative, and lymphocyte predominant pleural effusion with adenosine deaminase level 16 U/L. No malignant cell or acid fast bacilli were seen in pleural fluid. Contrast enhanced computed tomography (CECT) of thorax showed only right-sided pleural effusion (Figure 2). No mass lesion or mediastinal lymphadenopathy was detected on CECT thorax. Closed pleural biopsy was done with Abram's needle and histopathological examination of biopsy tissue taken from right parietal pleura showed diffuse sheets of round to oval cells with hyperchromatic nuclei and scant to moderate amount of cytoplasm. Few scattered large cells with abundant eosinophilic cytoplasm were present. Focally spindle cells with hyperchromatic nuclei were seen. Focal micropapillae formation was also noted; features were suggestive of a poorly differentiated malignant tumour (Figure 3). Immunohistochemistry of pleural tissue showed that majority of tumour cells were positive for synaptophysin and a few cells were positive for Ki-67 (2%) and negative for pan-cytokeratin, calretinin, Wilm's tumour protein 1 (WT1), desmin, vimentin, carcinoembryonic antigen (CEA), thyroid transcription factor 1 (TTF1), and CD 56 (Figure 4). Hence, tissue diagnosis was well-differentiated malignant neuroendocrine tumour of pleura. Histopathology and IHC findings were reviewed by another pathologist of different centre, and the diagnosis was confirmed. Fibreoptic bronchoscopy (FOB) was normal. CECT of abdomen and brain revealed no abnormality. No abnormality was detected on endoscopic examination of upper gastrointestinal tract and on colonoscopy. Radionuclide bone scan did not show any metastatic deposit in bones. So, final diagnosis was primary, well-differentiated, malignant neuroendocrine tumour of pleura, presenting as isolated right-sided pleural effusion.
Six cycles of cytotoxic chemotherapy comprising of intravenous infusion of carboplatin (at an area under the concentration-time curve 6.0 on day 1, 450 mg in this case) and etoposide (100 mg/m2/day, 130 mg in this case on days 1, 2, and 3) were given. Along with chemotherapy, intercostal tube drainage under water seal was given in right hemithorax through fifth intercostal space at right midaxillary line, as recurrent and rapid collection of massive amount of pleural fluid occurred and repeated aspiration of pleural fluid failed to reduce the volume of pleural fluid. When there was clinicoradiological evidence of complete expansion of right lung parenchyma, chemical pleurodesis with 20 mL of 10% povidone-iodine was done. On one-year follow-up, progressive regression of pleural effusion with alleviation of chest pain was documented.