Response to spray cryotherapy in a patient with adenocarcinoma in the parietal pleura

Malignancies of the parietal pleura, whether primary or metastatic, are a therapeutic challenge, and current therapies target their symptoms and not their tumor burden. Therefore, alternatives to standard approaches seem warranted. A patient with a parietal pleura-based adenocarcinoma was treated with low-pressure spray cryotherapy after failing more traditional approaches. The patient underwent therapeutic pleuroscopy with moderate sedation and local analgesia of the right chest. She was treated with the CSA Medical spray cryotherapy system, which was introduced into the chest via the working channel of a semi-rigid pleuroscope. Pleuroscopic examination 3 days after spray cryotherapy revealed >50% reduction in tumor size. No adverse events or complications occurred as a result of treatment. At the 3-month follow-up, a slightly raised mound of tissue was noted at the treatment site. This area was biopsied and found to be negative for tumor, containing only chronic inflammatory tissue. No evidence of residual cancer was observed. Initial observations include lack of a bystander effect on lung and pleura; no significant side effects or symptoms; a 50% tumoricidal response 3 days after treatment, and a complete tumoricidal response 90 days after treatment without evidence of tumor on the parietal pleura.