En bloc resection and aortic reconstruction for giant retroperitoneal teratoma with encasement of aorta

Abstract

Teratomas are nonseminomatous germ cell tumors typically managed with platinum-based chemotherapy followed by resection of residual disease. We report the case of a 29-year-old man with metastatic nonseminomatous testicular cancer who developed a persistent 16 cm postchemotherapy retroperitoneal teratoma encasing the supraceliac and infrarenal aorta and involving the left renal hilum. He underwent open resection through a midline transperitoneal approach with mediastinal tumor resection, en bloc aortic resection, extended left nephrectomy, and juxtarenal aortic reconstruction using a rifampin-soaked polyester graft to achieve microscopically margin-negative (R0) complete resection. Postoperatively, he had transient renal dysfunction and a chyle leak requiring intervention. At the 3-year follow-up, he remained disease-free.

Germ cell tumors are the most common solid cancers in young adult men and typically arise in the testis.¹ Modern chemotherapy achieves high cure rates, even with metastatic disease.¹ However, a substantial subset of patients with stages II to III disease have a residual retroperitoneal mass with possible vascular involvement after systemic therapy. Residual teratoma is chemotherapy-resistant, and complete surgical resection is recommended due to continued growth, local invasion, and potential malignant transformation despite benign histology. Large-volume postchemotherapy retroperitoneal resections often require meticulous dissection and reconstruction of adjacent arterial and venous vasculature.1, 2, 3 We present a patient with a large residual retroperitoneal and left supraclavicular mass following chemotherapy for retroperitoneal teratoma, treated by extensive resection requiring aortic reconstruction and nephrectomy to achieve complete (R0) resection. Study publication consent was received from the patient.

Case report

A 29-year-old man with nonseminomatous testicular cancer and metastatic disease (supraclavicular and hilar lymphadenopathy with pulmonary nodules) was treated with orchiectomy and systemic chemotherapy. Postchemotherapy imaging showed resolution of hilar and pulmonary disease but a persistent left supraclavicular mass and 16-cm retroperitoneal mass encasing the juxta- and infrarenal aorta, involving the left renal hilar vessels and left ureter, and extending posterior to the aorta to the lower mediastinum (Fig 1). The supraclavicular mass was confirmed by percutaneous biopsy to be metastatic teratoma and was resected through a left transcervical approach. He was subsequently referred for resection of the persistent retroperitoneal mass because of abdominal pain, nausea, constipation, and concern for progressive local invasion.

Fig 1.

A-C, Coronal, axial and sagittal images from the patient’s abdomen and pelvis computed tomography angiogram, demonstrating a persistent 16-cm retroperitoneal mass after chemotherapy. The mass encases the juxta- and infrarenal aorta, involves the left renal hilar vessels and left ureter, and extends posterior to the aorta to the level of the lower mediastinum. (D) Axial post-operative computed tomography angiogram images.

Operative approach

The operation was performed using a midline transperitoneal approach. An Omni self-retaining retractor (Omni-Tract Surgical) was used in standard fashion. The supraceliac aorta was exposed via the lesser sac with division of the diaphragmatic crura (Fig 2, A). The supraceliac segment of the mass was separated from the posterior and left lateral aortic wall, which was not directly involved. Two pairs of lower intercostal arteries arising from the supraceliac aorta were ligated and divided. Once this step was completed, an extended Kocher and Cattel-Braasch maneuver was performed to expose the right lateral wall of the aorta and the inferior vena cava (IVC) (Fig 2, B). The suprarenal retroaortic portion of the tumor mass was painstakingly dissected free, skeletonized, and separated from the aorta to the level of the renal arteries. Multiple pairs of lumbar arteries and veins were ligated and divided. The IVC and right renal vasculature were not involved. The mesocolon was retracted cephalad and mesentery to the right side of the abdomen. The large infracolic tumor mass was exposed. The left renal artery and vein were dissected free, ligated, and divided after a decision was made to proceed with left nephrectomy due to involvement of the left renal hilum and ureter, making partial nephrectomy or renal autotransplantation not feasible. The suprarenal aorta, superior mesenteric artery, and right renal artery were dissected free and controlled with Devon vessel loupes (Dow). The aorta was circumferentially free of tumor above the renal arteries and below for 1-cm length, but it was completely encased by tumor below this level. Both common iliac arteries were dissected free, and the left kidney was fully mobilized (Fig 3). The patient was systematically heparinized. The infrarenal aorta and common iliac arteries were clamped. The aorta was transected flush at the level of the clamp. En bloc resection of the entire tumor mass along with left kidney was completed. The tumor was circumferentially resected to the level of the anterior spinal ligament and to the border of the IVC on the right and psoas muscle on the left side. Numerous pairs of lumbar collateral branches were ligated and divided. Following complete removal of the specimen, the clamp was transferred to the supramesenteric position. A beveled rifampin soaked 16 mm polyester graft was anastomosed end-to-end to the juxtarenal aorta using running 4-0 Prolene suture with felt strip. The clamp was transferred to the infrarenal position after a total suprarenal ischemia time of 15 minutes. The straight graft was anastomosed distally to the aortic bifurcation (Fig 4). Heparinization was reversed. Due to denuding of the right renal artery adventitia during the dissection, the right renal artery was circumferentially wrapped with bovine pericardium without clamp. The graft was reinforced with a 360-degree omental wrap (Fig 5). Due to pleural entry occurred during tumor mobilization, and a right-sided chest tube was placed. The patient was transferred intubated to the intensive care unit hemodynamically stable and without vasopressor support. The patient was extubated on postoperative day (POD) 1. Serum creatinine peaked at 1.47 mg/dL on POD 1 and returned to baseline (1.26 mg/dL) later that same day. He was discharged home on POD 12 without major complications. A low-volume chyle leak developed and was initially managed conservatively and then treated by lymphatic embolization on POD 16. At the 3-year follow-up, computed tomography angiography showed no evidence of recurrent disease. Ongoing multidisciplinary surveillance includes serial cross-sectional imaging of the chest, abdomen, and pelvis with tumor-marker assessment.

Fig 2.

A, Depicting the exposure and Omni self-retaining retractor set up. The supraceliac aorta was exposed through the lesser sac with division of the diaphragmatic crura, and the supraceliac portion of the mass was mobilized off the posterior and lateral aortic wall. B, An extended Kocher and Cattell-Braasch maneuver was performed to expose the right lateral wall of the aorta and the inferior vena cava as well as posterior aortic dissection. Bilateral renal arteries as well as superior mesenteric and ciliac artery are partially visualized.

Fig 3.

C, Gross tumor exposed with illustration of extent of aortic encasement. D, The suprarenal aorta, superior mesenteric artery, and right renal artery were dissected and controlled with Silastic vessel loops. The aorta was circumferentially free of tumor for approximately 1 cm above and below the renal arteries. Both common iliac arteries were dissected and controlled, and the left kidney was fully mobilized.

Fig 4.

E, A rifampin-soaked 16-mm beveled polyester graft was anastomosed end-to-end to the juxtarenal aorta with running 4-0 Prolene and felt reinforcement. F, Completion reconstruction.

Fig 5.

G, 360-degree omental wrap of the reconstruction. H, Gross specimen following en bloc resection of the retroperitoneal tumor mass with nephrectomy.

Discussion

Resection of retroperitoneal teratomas involving major vascular structures is complex but feasible, requires multidisciplinary expertise and careful selection, and remains central to cure in metastatic nonseminomatous germ cell tumors.² Case reports show that vascular infiltration often necessitates en bloc resection with vascular reconstruction, including abdominal aorta and IVC replacement.4, 5, 6, 7, 8, 9, 10, 11, 12, 13

Residual tumor size and International Germ Cell Cancer Collaborative Group risk classification have been shown to predict the need for additional vascular procedures during postchemotherapy retroperitoneal lymph node dissection. In this high-risk subgroup, 20.4% of patients with residual tumors ≥5 cm required an IVC intervention.¹¹ Prosthetic polyester grafts are typically used for arterial and externally supported polytetrafluoroethylene grafts for venous reconstruction, whereas autologous tissue may be needed with enteric or urinary contamination.^14,15 The increased surgical difficulty often results from previous operations and scarred field, inflammation, and the large size of the tumor mass often with involvement of vascular structures. Dense desmoplastic reaction and obliteration of normal tissue planes increase the risk of major vascular injury and incomplete resection. Despite morbidity up to 25%, these procedures can have acceptable perioperative mortality at experienced centers and offer long-term survival, particularly with complete resection5, 6, 7, 8, 9, 10, 11, 12, 13, 14^,16; referral to high-volume multidisciplinary centers is recommended.

In this case, the tumor above the renal arteries was separated from the aorta without compromising oncologic margins. However, the aorta was completely encased by tumor in the infrarenal segment; to minimize renal and mesenteric ischemia, the surgical clamp was first applied below the renal arteries to allow removal of the specimen, followed by repositioning the clamp above the superior mesenteric artery for the proximal anastomosis of the graft. In situ renal cooling or selective renal perfusion was not used because the anticipated suprarenal ischemia time was short, and added manipulation was unlikely to benefit the patient but could have injured the extensively dissected right renal artery. Avoiding dissection in the subadventitial plane is critical to prevent inadvertent arterial disruption. Adjunctive measures, such as omental coverage of prosthetic material and routine retroperitoneal drainage, may reduce infectious and lymphatic complications. Chyle leak remains an anticipated complication after extensive retroperitoneal dissection, and lymphatic embolization is an effective minimally invasive option when conservative therapy fails.¹

Finally, adjunctive nephrectomy during postchemotherapy retroperitoneal surgery may be required when the renal hilum or ureter are inseparable from tumor. Although nephrectomy decreases renal reserve, it does not necessarily preclude subsequent adjuvant or salvage chemotherapy if relapse occurs, underscoring the importance of achieving complete resection when technically required.¹³

Conclusions

Large postchemotherapy retroperitoneal teratomas can encase major vessels and require complex vascular techniques to achieve complete oncologic resection. This case highlights the feasibility of en bloc aortic resection with prosthetic reconstruction and nephrectomy to obtain an R0 resection, emphasizing multidisciplinary planning and anticipation of lymphatic and renal complications.

IRB and informed consent

Per our institutional Committee for the Protection of Human Subjects, case reports are not considered research involving human subjects and therefore do not require previous Institutional Review Board (IRB) review or approval. The participant provided informed consent before enrollment. No identifiable patient information has been included.

Funding

None.

Disclosures

None.