Cytoreductive Surgery with Radical Pleurectomy/Decortication and Intraoperative photodynamic therapy as a treatment for Stage IVa and pleural recurrence thymic tumors

Managing stage IV thymoma with pleural spread or recurrence remains a complex clinical challenge. While complete resection is considered essential for achieving long-term survival, its feasibility and outcomes vary. Inspired by surgical strategies used in malignant pleural mesothelioma, we applied a multimodal approach combining extensive thymectomy, cytoreductive lung-preserving pleurectomy/decortication, and intraoperative photodynamic therapy (PDT) to enhance local control and survival outcomes. We retrospectively analyzed cases from April 2006 to December 2010 involving patients who underwent extended thymectomy, lung-sparing pleurectomy/decortication, and adjunctive intraoperative photodynamic therapy (PDT) for pleural thymic malignancies at our institution. The surgical technique was adapted from the methodology established by Dr. Friedberg at the Presbyterian Medical Center of the University of Pennsylvania. Intravenous sodium porfimer (2 mg/kg) was administered 48 hours prior to surgery, and the entire pleural cavity was illuminated with 630 nm light at a total dose of 30 J/cm² during the procedure. Each patient received only a single PDT session intraoperatively. Fifteen patients (4 men and 11 women; mean age: 43.9 years) were included, comprising six with de novo stage IVa disease and nine with pleural recurrence after initial thymoma resection. Histologically, 14 had thymoma and one had thymic carcinoma. Myasthenia gravis coexisted in 11 cases and was managed preoperatively with plasmapheresis. Six patients underwent upfront surgery; the others received neoadjuvant chemoradiotherapy. Surgical access was determined by tumor distribution: VATS (n=1), thoracotomy (n=9), sternotomy (n=4), and clamshell incision (n=1). In 11 patients, radical P/D was supplemented by pericardial and diaphragmatic resection. All patients underwent intraoperative PDT following gross total resection. Postoperative complications included two cases of chylothorax, both successfully managed conservatively, and one perioperative death due to hemorrhage. One patient was lost to follow-up; the remaining 13 patients received adjuvant chest wall irradiation and systemic chemotherapy. Local or pleural recurrence occurred in six patients and was managed with salvage surgery and/or additional oncologic treatments. One patient died from complications related to a repeat procedure, while another patient with thymic carcinoma subsequently developed distant metastases. No cases of skin burn injury were observed; only transient skin hyperpigmentation was noted. Over a mean follow-up of 106.8 ± 65.4 months, median recurrence-free survival was 75 ± 34.4 months (61.5% at 5 years, 36.9% at 10 years), and median overall survival reached 104 ± 23.4 months (69.2% at 5 years, 38.5% at 10 years). Three individuals remain alive: one with no recurrence for 205 months, and two with recurrent disease who are alive at 172 and 186 months, respectively, following additional treatment. A comprehensive surgical approach combined with intraoperative photodynamic therapy may offer improved regional disease control and extended survival in patients with advanced or pleural recurrent thymoma.