Hyperthermic intrathoracic chemotherapy (HITHOC) in stage IVA thymomas: a narrative review

Background and Objective: While surgery remains a cornerstone of thymoma treatment, its role as a standalone therapy is limited in ensuring adequate local disease control, particularly in cases involving serous dissemination or recurrence. For disseminated disease, various multidisciplinary approaches have been explored, including systemic chemotherapy and radiotherapy, either as standalone treatments or in combination with surgery. The efficacy is unsatisfactory, and the management is anything but standardized. However, recently, a promising technique has been introduced within the therapeutic algorithm of advanced stage thymomas: the hyperthermic intrathoracic chemotherapy (HITHOC) as an adjunct to surgery. By combining cytoreductive surgery with localized heated chemotherapy perfusion, HITHOC may help in treating residual disease, providing a targeted approach to pleural dissemination. HITHOC has demonstrated efficacy in managing stage IVA thymomas and thymoma-related pleural recurrences, establishing itself as a potential critical component of modern multimodal treatment strategies. This narrative review aims at providing a detailed examination of the mechanisms, indications, procedural aspects, and outcomes of HITHOC in pleural localization of thymomas, as well as its future potential in thoracic oncology. Methods: A literature search was performed using the MEDLINE and Google Scholar databases, including original full-length articles, meta-analyses, review articles, and case reports published up to January 2025. Key Content and Findings: HITHOC has been developed as an adjunct to macroscopic radical pleural tumor resection. By enhancing local tumor control and lowering recurrence rates, HITHOC provides a valuable addition to the multimodal treatment of advanced thymomas. Conclusions: HITHOC may represent a promising approach in the treatment of advanced thymomas with pleural dissemination. By combining cytoreductive surgery with localized hyperthermic chemotherapy, it may address the limitations of conventional therapies, potentially offering improved local disease control and survival.