Retroperitoneal tumour resection in fifteen consecutive cases: Single centre experience

Summary

Introduction: Retroperitoneal tumours (RTs) in adults are a rare heterogeneous group of neoplasms arising from the retroperitoneal space. RTs’clinical manifestations are nonspecific and depend on their anatomical positioning and relation with bordering structures. Our study aimed to retrospectively evaluate our patients’ diagnosis, length of hospital stay, disease-free period and postoperative metastasis occurrence.

Methods: From 2011 to 2019, fifteen suspected RT resections were performed at our centre. Retrospective analysis of patients’ hospital stays, follow-up, histological and immunological tumour profile, and metastasis occurrence/ re-occurrence was performed.

Result: All of the 15 (100%) patients were males. The average age of our patients was 44 years (SD ± 11.2 years), average hospital stay was 7.4 days (SD±3.4 days) (Tab.1). All resected tumours underwent histological and immunological evaluation. Based on histological examination of the resected tumours, nonseminomatous germ cell tumours were present in 12 (80%) patients – including teratoma in 4 (26.6%) patients, seminoma in 2 (13.3%) patients, and malignant B-cell lymphoma in 1 (6.6%) patient. The average patient follow-up was 42.7 months (SD±31.4.9 months). Complete remission after the surgery was achieved in 11 (76.9%) patients, and 2 (13.3%) patients were lost in follow-up.

Conclusion: RT is a rare heterogeneous group of neoplasm. The patient’s prognosis dramatically depends on the type of tumour, metastasis occurrence and re-occurrence, and the surgeons’ ability to resect the tumour completely.

Keywords:

resection – treatment – tumours – retroperitoneal – surgical

INTRODUCTION

Retroperitoneal tumours (RTs) in adults are a rare heterogeneous group of neoplasm arising from the retroperitoneal space with an incidence of 0.2–0.5% [1]. RTs are more prevalent in older adults. They can occur at an age [2]. Approximately 75% of RTs are of mesenchymal origin [3]. RTs’ clinical manifestations are nonspecific and depend on their anatomical location and relation with bordering structures. Surgical resection is challenging due to the RT anatomical location, dimensions, and proximity to the retroperitoneal and neighbouring vascular structures [4]. Complete and safe resection of a RT is possible, but organ and major vascular resections are frequently required to complete the procedure [6]. These factors can affect local recurrence, completeness of resection, postoperative outcomes and long-term survival rates of patients [5]. For the most part, these factors, including distant metastasis, are affected by RT biology. Complete surgical resection, especially for malignant RTs, has an immense impact on longterm patient survival [6,7]. Our study aimed to retrospectively evaluate our patients’ diagnosis, length of hospital stay, disease-free period and postoperative metastasis occurrence.

METHODS

From 2011 to 2019, fifteen patients with RT diagnosed based on computer tomography evaluation or biopsy results underwent open RT resection. We performed a retrospective analysis of the patients’ diagnosis, histological and immunological tumour evaluation, hospital stay, follow-up, metastasis occurrence/re-occurrence, and survival.

RESULTS

All of the 15 (100%) patients were males. The average age of our patients was 44 years (SD±11.2 years), average hospital stay was 7.4 days (SD±3.4 days).

The average patient follow-up was 42.7 months (SD±31.4.9 months). Complete remission after the surgery was achieved in 11 (76.9%) patients, and 3 (20%) patients underwent chemotherapy. Two (13.3%) patients had lung metastasis during their oncologic follow- up. 2 (13.3%) patients were lost during oncologic follow-up. Three (20%) patients required chemotherapy, and one (6.6%) patient died 70 months after the surgery (Tab.1).

All resected tumours underwent histological and immunological evaluation. Based on histological examination of the resected tumours, nonseminomatous germ cell tumours were present in 12 (80%) patients (including teratoma in 4 [26.6%] patients), seminoma in 2 (13.3%) patients, and malignant B-cell lymphoma in 1(6.6%) patients (Tab. 2).

DISCUSSION

RTs are defined as neoplasms not derived from tissue typical of kidneys, adrenal glands, pancreas, or bowel loops. The retroperitoneal space is divided into compartments: anterior pararenal space, posterior pararenal space, and perirenal space. RTs are located in the retroperitoneal space extending from the diaphragm to the pelvis, posteriorly bordered by the transverse fascia and anteriorly by the posterior parietal peritoneum. The retroperitoneum also includes a central region containing the aorta and inferior vena cava, as well as lymphatic chains and the nerve plexuses [8,11].

If a RT meets the above mentioned histological and anatomical criteria, it is classified as primary and is categorized as solid or cystic depending on its imaging [9]. Solid RTs are divided into four groups based on their origin: mesenchymal, neural, germ-cell, and lymphoproliferative. Cystic RT includes lymphangiomas and cystic mesotheliomas. Non-neoplastic processes resulting in a retroperitoneal mass include retroperitoneal fibrosis, non-Langerhans histiocytosis (Erdheim-Chester disease), and extramedullary haematopoiesis [10]. Approximately 70%–80% of primary retroperitoneal neoplasms are malignant [11].

Even though there is an overlap of imaging modalities, the gold standard in imaging methods and diagnostics are computed tomography (CT) and magnetic resonance imaging (MRI) [12]. Both CT and MRI are used in the differential diagnosis of RT, tumour staging, biopsy guiding, and surgical strategy planning [13,14].

The spectrum of RTs in surgical series is determined by the specialization of the centre and by referral pathways. A large single-centre series suggests that most RTs are malignant [1,15]. For malignant RT, the completeness of surgical resection is a critical prognostic factor for patient survival [16]. Due to the immense role of complete surgical resection in patients with malignant RT, newly proposed revised staging systems incorporate this factor into the staging system and survival nomogram [7]. However, complete surgical resection is often difficult due to the RT anatomical location and interaction with neighbouring structures and vasculature [4]. Major intraabdominal vasculature is involved in up to 18%. Right-sided tumours most frequently affect the inferior vena cava (IVC). Resection of the IVC is frequently required. IVC resection and synthetic graft substitution have a patency ranging from 90–94% in 36 months. Aortic resection using synthetic graft have a reported patency of 89% in 19 months [17]. Multi-organ resection is required in 80% of patients. The kidney is the most common en bloc resected organ. This fact underlines the importance of preoperative planning [16].

Newly some centres are in favour of “complete compartmental surgery”. The available data suggests that despite a 3-fold decrease in local recurrence, there is no difference in patient survival [18]. Furthermore, Santos et al. showed that “complete compartmental surgery” is associated with higher per-operative risk and postoperative morbidity in tumours with unfavourable anatomical localization [19]. Only a small RT with favourable anatomical localization benefits from compartmental resection [20].

The limitation of our analysis is the small number of patients with diverse histological tumour diagnoses, not allowing us to conclude patients’ short- and longterm survival, the occurrence of metastasis, and the success of the surgical procedure.

CONCLUSION

RT is a rare heterogeneous group of neoplasm. The patient’s prognosis dramatically depends on the type of tumour, metastasis occurrence and re-occurrence, and the surgeon’s ability to resect the tumour completely. Cooperation between surgeons and oncologists plays a crucial and fundamental role in patients’ survival. Early tumour diagnosis, resection planning, postoperative oncological screening, and chemotherapy are essential for survival.

Conflict of interests

The authors declare that they have not conflict of interest in connection with this paper and that the article has not been published in any other journal, except congress abstracts and clinical guidelines.

MUDr. Robert Novotny,

Department of Transplant Surgery,

Institute for Clinical and Experimental Medicine,

Videnska 1958/9

Prague

e-mail: novr@ikem.cz