Parenchymal splenic metastasis is an independent negative predictor of overall survival in advanced ovarian, fallopian tube, and primary peritoneal cancer

Neglected Anatomical Areas in Ovarian Cancer: Significance for Optimal Debulking Surgery

Ovarian cancer (OC), the most lethal gynecological malignancy, usually presents in advanced stages. Characterized by peritoneal and lymphatic dissemination, OC necessitates a complex surgical approach usually involving the upper abdomen with the aim of achieving optimal cytoreduction without visible macroscopic disease (R0). Failures in optimal cytoreduction, essential for prognosis, often stem from overlooking anatomical neglected sites that harbor residual tumor. Concealed OC metastases may be found in anatomical locations such as the omental bursa; Morison's pouch; the base of the round ligament and hepatic bridge; the splenic hilum; and suprarenal, retrocrural, cardiophrenic and inguinal lymph nodes. Hence, mastery of anatomy is crucial, given the necessity for maneuvers like liver mobilization, diaphragmatic peritonectomy and splenectomy, as well as dissection of suprarenal, celiac, and cardiophrenic lymph nodes in most cases. This article provides a meticulous anatomical description of neglected anatomical areas during OC surgery and describes surgical steps essential for the dissection of these "neglected" areas. This knowledge should equip clinicians with the tools needed for safe and complete cytoreduction in OC patients.

Splenectomy in epithelial ovarian cancer surgery

OBJECTIVE

Splenectomy is performed in 4-32% of cytoreductive surgeries for ovarian cancer. The objective of our study was to assess splenectomy and evaluate its impact on overall and disease-free survival.

METHODS

We conducted a retrospective single-center study between January 2000 and December 2016. Patients who underwent a cytoreduction for epithelial ovarian cancer, regardless of stage and surgical approach, were eligible for the study. Patients deemed not operable were excluded from the study. Patients were stratified into two groups, splenectomy or no splenectomy. A univariate analysis followed by a multivariate analysis was conducted to evaluate the postoperative complications after splenectomy and the overall and disease-free survival.

RESULTS

This cohort included 464 patients. Disease stages, peritoneal carcinomatosis scores, and the rate of radical surgery (Pomel classification) were significantly higher in the splenectomy group, p=0.04, p<0.0001, and p<0.001, respectively. However, no significant difference was found in the rate of complete cytoreduction between the two groups (p=0.26) after multivariate analysis. In univariate analysis, splenectomy was significantly associated with extensive surgical procedures. In multivariate analysis, the two more prevalent complications in the splenectomy group were the risk of abdominopelvic lymphocele (overall response (OR) =4.2; p=0.01) and blood transfusion (OR=2.4; p=0.008). The average length of hospital stay was significantly longer in the splenectomy group, 17.4 vs 14.6 days (p<0.0001). The delay in adjuvant chemotherapy was longer in the splenectomy group (p=0.001). There was no significant difference in overall and disease-free survival (p=0.09) and (p=0.79), respectively.

CONCLUSION

Splenectomy may be considered an acceptable and safe procedure; however, with no impact on overall or disease-free survival. In addition, it is associated with longer hospital stay and longer time to chemotherapy.

Upper-Abdominal Cytoreduction for Advanced Ovarian Cancer—Therapeutic Rationale, Surgical Anatomy and Techniques of Cytoreduction

Cytoreductive surgery (CRS) is the cornerstone of treating advanced ovarian cancer. Approximately 60–70% of patients with advanced ovarian cancer will have involvement in the upper abdomen or the supracolic compartment of the abdominal cavity. Though the involvement of this region results in poorer survival compared, complete cytoreduction benefits overall survival, making upper-abdominal cytoreduction an essential component of CRS for advanced ovarian cancer. The upper abdomen constitutes several vital organs and large blood vessels draped with the parietal or visceral peritoneum, common sites of disease in ovarian cancer. A surgeon treating advanced ovarian cancer should be well versed in upper-abdominal cytoreduction techniques, including diaphragmatic peritonectomy and diaphragm resection, lesser omentectomy, splenectomy with or without distal pancreatectomy, liver resection, cholecystectomy, and suprarenal retroperitoneal lymphadenectomy. Other procedures such as clearance of the periportal region, Glisson’s capsulectomy, clearance of the superior recess of the lesser sac, and Morrison’s pouch are essential as these regions are often involved in ovarian cancer. This manuscript covers the surgical anatomy of the upper abdomen, the techniques and therapeutic rationale of upper-abdominal cytoreduction, and specific measures for perioperative management of these patients. The main focus is the description of various peritonectomies and regional lymphadenectomies.

Oncologic outcomes after splenectomy during initial cytoreductive surgery in advanced epithelial ovarian cancer: a nationwide population-based cohort study

INTRODUCTION

Epithelial ovarian cancer (EOC) patients undergoing splenectomy during cytoreductive surgery represent a small subgroup of patients. Splenic metastases or technical reasons due to extensive upper abdominal disease may require a splenectomy. It has been hypothesized that as the spleen's antitumor immunologic functions may inhibit cancer growth, splenectomy may promote the growth of residual disease as observed in other cancer types of murine studies. The few studies assessing the impact of splenectomy on the oncologic outcomes of advanced stage EOC patients have reported inconsistent results. It remains unclear whether splenectomy during cytoreductive surgery is justified to achieve complete cytoreduction. The aim of this study was to assess the impact of a splenectomy on perioperative outcomes and survival of advanced stage EOC patients.

MATERIAL AND METHODS

In this nationwide population-based study, all consecutive patients diagnosed with FIGO stage IIIC and IV EOC between 1 January 2008 and 31 December 2015 were identified from the Netherlands Cancer Registry. Patients who underwent cytoreductive surgery combined with platinum-based chemotherapy as primary treatment were selected. Differences in clinicopathologic characteristics between splenectomy and non-splenectomy patients were assessed. Progression-free survival (PFS) and overall survival (OS) were analyzed using Kaplan-Meier survival curves and log-rank tests. Cox proportional hazards models were used to adjust for covariates that influence survival.

RESULTS

A total of 3911 patients were identified: 99 splenectomy and 3812 non-splenectomy patients. Splenectomy patients were more likely to undergo extensive surgery or surgical reintervention, to receive intraperitoneal chemotherapy, intraoperative and postoperative blood transfusion, to experience postoperative infections, and to be admitted to an intensive care unit (all p < 0.002). No significant differences in PFS or OS were observed between splenectomy versus non-splenectomy patients after adjusting for covariates.

CONCLUSIONS

Although advanced stage EOC patients who undergo splenectomy during cytoreductive surgery have less favorable perioperative outcomes, no adverse impact of splenectomy on the survival of advanced stage EOC patients was observed. Splenectomy during cytoreductive surgery seems to be justified to achieve complete cytoreduction in advanced stage EOC patients.

Does the Performance of Splenectomy as Part of Cytoreductive Surgery Carry a Worse Prognosis Than in Patients Not Receiving Splenectomy? A Propensity Score Analysis and Review of the Literature

BACKGROUND & OBJECTIVES

Ultra-radical (UR) procedures, including splenectomy, are utilized to increase complete cytoreduction rates during Cytoreductive Surgery (CRS) performed with the aim of complete macroscopic clearance of disease. The purpose of this study was to investigate if splenectomy negatively impacts survival when undertaken during CRS for advanced ovarian cancer (AOC) and compare published splenectomy and cytoreduction rates.

METHODS

A retrospective review of all consecutive patients who underwent cytoreductive surgery for AOC between 16/05/2013-28/01/2019. Survival, baseline patient characteristics, complications and surgical parameters were recorded. Propensity scored matching (PSM) was performed to reduce bias.

RESULTS

154 patients identified over 71 months. 97 underwent standard, 57 underwent UR surgery, 27 patients received splenectomy (17.5%) No difference was seen in overall survival (OS) between all patients (median OS 34 months (95%CI 25.9-41.1) and patients who underwent splenectomy (median OS not yet reached) (p = >0.05). After PSM for various baseline covariates, no significant difference in splenectomy versus non-splenectomy patients (3-year survival 54% compared to 56%) (P > 0.05). Three splenectomy specific complications occurred; one each of pancreatic tail injury, left pleural effusion and streptococcal pharyngitis during chemotherapy. We found wide variation in utilization of splenectomy in published case series; from 9% to 35%.

CONCLUSIONS

Splenectomy performed as part of CRS is not detrimental to survival in AOC. There is a wide variation in utilization of splenectomy in published case series with little correlation with cytoreduction rates.

Metastasis patterns of the spleen and association with survival outcomes in advanced ovarian-tubal-peritoneal epithelial cancer

PURPOSE

To evaluate the significance of parenchymal, hilar and capsular involvement of the spleen with regard to survival.

METHODS

All patients who underwent primary cytoreductive surgery for advanced ovarian-tubal-peritoneal (OTP) epithelial cancer were reviewed retrospectively. Stage 3C patients who had an upper abdomen involvement and who were optimally debulked were included. Patients who had abdomen-confined disease, but were upstaged to stage 4B due to splenic parenchymal metastases were also included.

RESULTS

Seventy four patients eligible with the inclusion criteria who underwent splenectomy and 69 patients who did not undergo splenectomy were included. The median follow-up time was 39.1 months. The median overall survival of the study group was 61.4 months. Patients who underwent splenectomy were grouped according to the involved site of the spleen: parenchyma subgroup, hilus subgroup, capsule subgroup and benign subgroup. The median overall survival of patients in the hilus subgroup was 41.1 months. The median overall survival of patients who were not in the hilus subgroup was 65.5 months. Patients in the hilus subgroup showed significantly shorter survival (p = 0.035). Hilus subgroup was associated with a statistically significant increase in mortality risk (hazard ratio 1.971; 95% confidence interval 1.1-3.531).

CONCLUSIONS

Splenic hilus involvement predicts poorer survival outcomes among stage 3C epithelial OTP cancer patients with disease expansion to upper abdomen. According to current study and many published studies, hilar involvement had a higher incidence rate compared to parenchymal involvement. Thus, hilar involvement would be a beneficial clinical predictor of survival for larger number of patients.

Molecular Mechanisms Regulating Organ-Specific Metastases in Epithelial Ovarian Carcinoma

Epithelial ovarian carcinoma is the most predominant type of ovarian carcinoma, the deadliest gynecologic malignancy. It is typically diagnosed late when the cancer has already metastasized. Transcoelomic metastasis is the most predominant mechanism of dissemination from epithelial ovarian carcinoma, although both hematogenously and lymphogenously spread metastases also occur. In this review, we describe molecular mechanisms known to regulate organ-specific metastasis from epithelial ovarian carcinoma. We begin by discussing the sites colonized by metastatic ovarian carcinoma and rank them in the order of prevalence. Next, we review the mechanisms regulating the transcoelomic metastasis. Within this chapter, we specifically focus on the mechanisms that were demonstrated to regulate peritoneal adhesion—one of the first steps in the transcoelomic metastatic cascade. Furthermore, we describe mechanisms of the transcoelomic metastasis known to regulate colonization of specific sites within the peritoneal cavity, including the omentum. Mechanisms underlying hematogenous and lymphogenous metastatic spread are less comprehensively studied in ovarian cancer, and we summarize mechanisms that were identified to date. Lastly, we discuss the outcomes of the clinical trials that attempted to target some of the mechanisms described in this review.