Sunitinib induced pleural...

Sunitinib Induced Pleural Effusion

Background:

Pleural effusion is the second most common presentation of extra-pulmonary tuberculosis. Drug induced pleural effusions is one of the rare causes of exudative pleural effusion encountered in day to day practice . High index of clinical suspicion leads to early diagnosis and helps to avoid inadvertent use of empirical anti tubercular drugs which unfortunately still remains a common practice in our country.

Case:

A 39 year old male, known case of metastatic gastro-intestinal stromal tumor (GIST) presented with right sided pleuritic chest pain for two weeks. Patient was on sunitinib for the last 9 months due to partial response to initial treatment with imatinib. Chest radiograph revealed a right costophrenic angle blunting suggestive of pleural effusion.

Investigations: 
- USG guided thoracentesis revealed the effusion to be straw coloured, exudative, monomorphic (70%) and low ADA (20 IU/ml). 
- Two consecutive samples sent for cytological analysis did not demonstrate any malignant cells. 
- CECT chest showed enlarged lymph node (LN) at 4R station; EBUS-TBNA from the same showed reactive lymphoid hyperplasia on cytology. 
- Microbiological workup of TBNA aspirate and BAL from right middle lobe came out to be negative.

Follow-up: 
- After ruling out the usual causes of exudative pleural effusions, Sunitinib was withheld being the suspected inciting drug. 
- After three weeks of stopping the drug, repeat chest radiograph and USG chest screening, showed resolution of pleural effusion. 
- Further plan for  oncological treatment is to be decided after multidisciplinary discussion.

Discussion: 
- Sunitinib is a receptor tyrosine kinase inhibitor. 
- Most common adverse events of sunitinib are hypertension, diarrhea, nausea and hematological toxicity. 
- To the best of our knowledge, this is the first reported case of sunitinib induced pleural effusion. 

Conclusion: 
- Our case demonstrates the importance of regular follow up and monitoring of patients on TKI therapy. 
- The usual suspects of exudative effusions in a pulmonary medicine OPD are Tubercular, parapneumonic and malignant effusions.
- However, diagnosis of drug induced effusions requires exclusion of other causes.
- Pleural effusion usually resolves spontaneously after cessation of the implicating drug.