Although lung metastasis excision in various types of tumors is well known and documented, the data is limited to the role of the surgery for metastases of urogenital cancers on literature (Table 5).
Considering the renal cell carcinoma, it was reported that 5-years survival rates are between 21% and 60% after pulmonary metastasectomy [2–8]. It was also shown that metastasectomy would have an additional contribution to prognosis, especially in patients with few and small metastases and longer DFI [5–9]. Our study demonstrated 2-years survival rates 66.6% from renal cell carcinoma, after pulmonary metastasectomy.
In literature, studies have demonstrated 5-years survival rates between 15,9%-%33 from urothelial carcinoma, after pulmonary metastasectomy [9–14]. It was also shown that patients who had shown great response to chemotherapy and had no evidence of early or rapid progression elsewhere had been shown to benefit more from metastasectomy. In our experience, we had four cases of metastatic urothelial carcinoma with a 57.1% 2-years survival rate. Adjuvant therapy was not administered after the pulmonary metastasectomy. There is limited data in the literature regarding the benefit of giving adjuvant treatment after complete metastasectomy in renal cell carcinoma. In these studies, there was no significant difference in survival in the group with and without systemic adjuvant therapy [15]. However, pulmonary metastasectomy combined with systemic targeted therapy and/or immunotherapy could be an optimal treatment approach in the future, but it needs to be supported by clinical trials.
The lung is the most common site of metastases in patients with testicular germ cell tumors. Studies demonstrated that resection of the pulmonary metastases has a positive effect on survival rates, especially patients with lesions limited to one site. In literature, 5-years survival rates were reported between 45%-65% after metastasectomy [16–22]. McGuire MS et al. have reviewed 105 patients with NSGCTs who undergone thoracotomy because of pulmonary metastasis and the viable non-teratomatous disease in the chest or retroperitoneum was described as a poor prognostic factor [18]. In another study, Pfannschmidt J et al. have reviewed 52 cases of NSGCT who undergone pulmonary metastasectomy, and 5-year survival was reported as 75.8%. The authors described incomplete resection and elevated tumor marker levels, AFP and/or hCG as poor prognostic factors [19]. In our study, we had 4 cases of testicular tumors which histological types were embryonal carcinoma. These patients underwent radical inguinal orchiectomy, retroperitoneal lymph node dissection, and adjuvant chemotherapy. However, because of metachronous pulmonary metastases, surgical resection was needed, and adjuvant chemotherapy was administered. The 2-years survival was detected as 50% after pulmonary metastasectomy.
Isolated solitary pulmonary metastases are extremely rare in prostate carcinomas. In prostate carcinoma, lung metastases usually present diffuse interstitial or multinodular patterns, and there is no clue about the survival benefit of pulmonary metastasectomy [23, 24]. Therefore, pulmonary metastasectomy should be performed only if the patient has solitary pulmonary metastasis resistant to hormone therapy or has severe respiratory symptoms refractory to conservative management. In our experience, we had only two patient of prostate carcinoma who underwent wedge resection. These two patients died in the first six postoperative month due to disease progression.
It is also important to choose the appropriate surgical method in patients with pulmonary metastases. Video-assisted thoracoscopic surgery (VATS) has well-documented benefits over open thoracotomy like less pain, less inflammatory response, shorter hospitalization and fast recovery after surgery [25–27]. The main concern regarding the use of VATS for metastasectomy is the risk of inability to performing complete resection. There isn’t any information in the literature to confirm these concerns. Several studies even reported no relation between VATS and open thoracotomy in recurrence in the ipsilateral lung [28, 29]. Therefore, VATS is routinely used in our clinic for pulmonary metastasectomy. Sometimes it would be difficult to localize metastatic nodules or ground-glass opacities (GGO) intraoperatively during the VATS procedure. Thankfully, various methods that make it possible to localize these kinds of lesions with the VATS technique have been described. The most commonly used methods for this purpose are methylene blue and hook wire marking [30]. We routinely use CT-guided methylene blue staining techniques in patients with small nodules and GGOs (Fig. 1). Although the lesion is localized with almost complete accuracy by these marking methods, the confirmation should be performed with a frozen section.
In highly selected patients, resection of pulmonary metastases present minimal risk and prolong survival in urogenital tumors. Previous studies described the presence of prolonged DFI, unilateral metastases, surgically resectable tumors, and less than 3 radioimagistic detectable metastases, as a positive predictive factor. With this study, we aim to evaluate the results of pulmonary metastasectomy in patients with primary urogenital tumors in our clinic.