Das thorakale Growing Teratoma Syndrom von nichtseminomatösen Keimzelltumoren: Eine interdisziplinäre Herausforderung

In our retrospective study, prospectively collected data were used to analyze the rare clinical presentation of 29 TGTS patients. Since the pathophysiological basis of a GTS is not clear, different theories still exist. Simultaneously, the diagnosis is proven challenging due to the pretreatment. The gold standard of therapy is the complete resection of the growing teratoma with a curative approach. On one hand, this clarifies the histology of the tumor and, on the other hand, minimizes the likelihood of a relapse or malignant transformation. We were able to achieve a complete resection in all patients with mostly extended resections. Due to their size, growing teratomas can cause compression phenomena or infiltration of important central structures. Because of this and its proximity to central structures, resection represents a surgical challenge. The thoracic growing teratomas in our collective data showed a median size of 64.5 mm (10-210 mm). We were able to detect multilocalized infestation in approximately every third patient (34.5%, n = 10). A total of 44 operations were performed, 25 of which were thoracotomies (including 6 double thoracotomies), 6 sternotomies, 7 transabdominal resections and 6 neck dissections. Regarding the prognosis, the following factors were examined in relation to survival: 1) patient's age at diagnosis (p = 0.140), 2) tumor size (p = 0.119), 3) multilocalisation of the TGTS (p = 0.159), 4) need for high-dose chemotherapy and autologous stem cell transplantation (p = 0.373), 5) necessity of an extended resection (p = 0.159) and 6) time of diagnosis of TGTS (p = 0.987) - during treatment of the primary tumor or during relapse. None of the above factors showed a significant impact on survival. The recognition of the rare syndrome, the interdisciplinary consultation and the understanding of the treatment strategy, are all critical for success. Thanks to this interdisciplinary approach, the optimal time point for the appropriate therapeutic approach can be precisely planned, while procedures unnecessary for the patient can be spared. In our patient population, this approach resulted in low morbidity, a 5-year and 10-year survival rate of 93%, and a 15-year survival rate of 84% without mortality. At the same time, only 14.3% (n=4) of the patients in total, suffered a relapse. Limitations of our study include the small patient population size, the retrospective study design and the absence of data such as IGCCCG-classification or the initial tumor markers. However, to the best of our knowledge, this is so far the largest group of TGTS patients, examined in literature, after testicular or extragonadal non-seminomatous germ cell tumors. In summary, the complexity of this disease requires close collaboration between oncologists, urologists and thoracic surgeons.