Impact of the surgical peritoneal environment on pre-implanted tumors on a molecular level: a syngeneic mouse model

Surgical peritoneal stress creates a pro-metastatic niche promoting resistance to apoptosis via IL-8

Background

The mainstay of treatment of advanced ovarian cancer (AOC) involves chemotherapy, and debulking surgery. However, despite optimal surgical procedure and adjuvant chemotherapy, 60% of patients with AOC will relapse within 5 years. Most recurrences occur in the peritoneal cavity, suggesting the existence of occult sanctuaries where ovarian cancer cells (OCC) are protected. In murine models, surgical stress favors tumor growth; however, it has never been established that surgery may affect OCC sensitivity to subsequent chemotherapy. In this study, we investigated how the surgical stress could affect the chemosensitivity of OCC.

Methods

To avoid bias due to tumor burden in peritoneal cavity and duration of surgery, we used peritoneal biopsies from patients without a malignancy at precise time points. During laparotomies, peritoneal biopsies at the incision site were performed at the time of incision (H0 sample) and 1 h after initiation of surgery (H1 sample). We evaluated the chemoresistance to Taxol (0–20 µM) induced by H0 or H1 incubation (24 h) in two ovarian cancer cell lines OVCAR3 and SKOV3 and a primary cancer cell lines derived in our laboratory.

Results

Our results indicate that stressed peritoneum overexpressed cytokines, resulting in OCC increased resistance to therapy. Among these cytokines, IL8 was responsible for the resistance to apoptosis through the AKT pathway activation. Chemoresistance in OCC persists through the establishment of an autocrine IL8 loop. Finally, in a cohort of 32 patients, we showed an impact of IL8 tumoral overexpression on chemosensitivity and survival outcomes with a significant association to earlier recurrence.

Conclusions

Our study demonstrated that precision surgery where targeted treatment would be used in combination with surgery is essential to obtain better tumor control.

Electronic supplementary material

The online version of this article (10.1186/s12967-018-1643-z) contains supplementary material, which is available to authorized users.

What is the evidence for the use of low-pressure pneumoperitoneum? A systematic review

Background

Laparoscopic surgery has several advantages when compared to open surgery, including faster postoperative recovery and lower pain scores. However, for laparoscopy, a pneumoperitoneum is required to create workspace between the abdominal wall and intraabdominal organs. Increased intraabdominal pressure may also have negative implications on cardiovascular, pulmonary, and intraabdominal organ functionings. To overcome these negative consequences, several trials have been performed comparing low- versus standard-pressure pneumoperitoneum.

Methods

A systematic review of all randomized controlled clinical trials and observational studies comparing low- versus standard-pressure pneumoperitoneum.

Results and conclusions

Quality assessment showed that the overall quality of evidence was moderate to low. Postoperative pain scores were reduced by the use of low-pressure pneumoperitoneum. With appropriate perioperative measures, the use of low-pressure pneumoperitoneum does not seem to have clinical advantages as compared to standard pressure on cardiac and pulmonary function. Although there are indications that low-pressure pneumoperitoneum is associated with less liver and kidney injury when compared to standard-pressure pneumoperitoneum, this does not seem to have clinical implications for healthy individuals. The influence of low-pressure pneumoperitoneum on adhesion formation, anastomosis healing, tumor metastasis, intraocular and intracerebral pressure, and thromboembolic complications remains uncertain, as no human clinical trials have been performed. The influence of pressure on surgical conditions and safety has not been established to date. In conclusion, the most important benefit of low-pressure pneumoperitoneum is lower postoperative pain scores, supported by a moderate quality of evidence. However, the quality of surgical conditions and safety of the use of low-pressure pneumoperitoneum need to be established, as are the values and preferences of physicians and patients regarding the potential benefits and risks. Therefore, the recommendation to use low-pressure pneumoperitoneum during laparoscopy is weak, and more studies are required.