THE EFFECT OF PNEUMOPERITONEUM ON DISSEMINATION AND SCAR IMPLANTATION OF INTRA-ABDOMINAL TUMOR CELLS

Robot-assisted retroperitoneal lymph node dissection: a systematic review of perioperative outcomes

OBJECTIVE

To assess the safety and feasibility of robot-assisted retroperitoneal lymph node dissection (R-RPLND) and to compare the perioperative outcomes of R-RPLND with open RPLND (O-RPLND), as RPLND forms an integral part of the management of testis cancer and R-RPLND is a minimally invasive treatment option for this disease.

MATERIALS AND METHODS

The PubMed^® , Scopus^® , Cochrane Central Register of Controlled Trials, and Web of Science™ databases were searched for studies reporting perioperative outcomes of primary and post-chemotherapy R-RPLND and studies comparing R-RPLND with O-RPLND.

RESULTS

The search yielded 42 articles describing R-RPLND, including five comparative studies. The systematic review included 4222 patients (single-arm studies, n = 459; comparative studies, n = 3763). Of 459 patients in the single-arm studies, 271 underwent primary R-RPLND and 188 underwent post-chemotherapy R-RPLND. For primary R-RPLND, the operative time ranged from 175 to 540 min and the major complication rate was 4.1%. For post-chemotherapy R-RPLND, the operative time ranged from 134 to 550 min and the major complication rate was 8.5%. The conversion rate to open surgery was 2.2% in primary R-RPLND and 9.0% in post-chemotherapy R-RPLND. In comparison with O-RPLND, R-RPLND was associated with a lower transfusion rate (14.5% vs 0.9%, P < 0.001) and a lower complication rate (18.5% vs 7.8%, P = 0.002).

CONCLUSION

Robot-assisted RPLND has acceptable perioperative outcomes in both the primary and post-chemotherapy settings but a notable rate of conversion to open surgery in the post-chemotherapy setting. Compared with O-RPLND, R-RPLND is associated with a lower transfusion rate and fewer overall complications. Given the potential impact of selection bias, the optimal patient selection criteria for R-RPLND remain to be elucidated.

The effect of CO2 pressure and flow variation on carbon particles spread during pneumoperitoneum: an experimental study

BACKGROUND

A correlation between atypical recurrences and minimally-invasive surgery has been suggested in case of urothelial cancer; however, very few data are available on the role of pneumo peritoneum in terms of gas flow and intra-abdominal pressure. The objective of the study is to analyze the impact of CO2 pneumoperitoneum variation on an inert material as surrogate of neoplastic cells.

MATERIAL AND METHODS

We designed an experimental model mimicking pneumoperitoneum in three settings: sealed flow (no leakage), pulsatile flow (alternating efflux and influx) and continuous flow (AirSeal® insufflator). Each experiment was characterized by a pre-determined gas flow and pressure, trocar distance and position from the particles. Hounsfield density (HD) variation in the areas of interest was measured as index of graphite powder dispersion. A Linear regression model was employed to measure the correlation between modifiable variables and HD.

RESULTS

HD was lower in the pulsatile compared to both the sealed and continuous flows (p < 0.03). On multivariate analysis for sealed setting, flow and total gas liters delivered (i.e. gas leakage) were inversely and independently related to HD (all p <0.03). In pulsatile setting, trocar position, trocar distance and gas flow independently predicted HD (all p <0.03). In continuous setting, gas pressure was directly and independently related to HD (p = 0.004) due to decreased pneumoperitoneum stability and increased CO2 liters delivered. In case of in-flow trocar positioned laterally to the particles, low flow (1 L/min) or low pressure (8 mmHg), HD values recorded in the three settings were all overlapping (all p > 0.05).

CONCLUSIONS

Flow and pressure setting, in-flow trocar distance and contiguity from the tumor, and pneumoperitoneum stability may be all crucial component in minimally invasive surgery. In vivo, these variables should be considered as potential risk factors for tumor cells spread within the abdominal cavity.

Port-site metastasis and atypical recurrences after robotic-assisted radical cystectomy (RARC): an updated comprehensive and systematic review of current evidences

The objective of this systematic review is to evaluate the current evidence regarding atypical metastases in patients undergoing robotic-assisted radical cystectomy (RARC). A review of the current literature was conducted through the Medline and NCBI PubMed, Cochrane Central Register of Controlled Trials (CENTRAL) and Google Scholar databases in October 2019. From the literature search using the cited keys and after a careful evaluation of the full texts, we included 31 articles in the study. Fourteen studies (45.2%) reported at least an atypical recurrence during the follow-up period with a rate between 4 and 40% of all the recurrences. Overall, 105 (1.63%) of the 6720 patients who have been evaluated in the included studies developed an atypical recurrence. Sixty-three (60%) of these atypical metastases were peritoneal carcinomatosis, 16 (15.2%) extrapelvic lymph nodes metastases, 11 (10.5%) port-site metastases, 10 (9.5%) retroperitoneal nodal metastases, while 5 (3.8%) patients developed more than one type of atypical recurrence. In literature, there is a low but not negligible incidence of atypical recurrences after RARC. However, publication bias and retrospective design of most studies could influence the evidences. Further prospective randomized studies are needed to clarify the real risk of patients undergoing RARC to develop atypical metastases.

Does carbon dioxide pneumoperitoneum enhance wound metastases following laparoscopic abdominal tumor surgery? A meta-analysis of 20 randomized control studies

The mechanisms involved in the development of wound metastasis following laparoscopic abdominal tumor surgery remain unclear. The aim of this study was to accurately assess whether the duration of carbon dioxide pneumoperitoneum (CDP) during laparoscopic abdominal tumor surgery enhances wound metastases. We conducted a systematic review of PubMed, Cochrane Library, and Embase through December 2013 to identify animal experiments comparing wound recurrence between laparoscopic and gasless laparoscopic procedures or open procedures. The outcome of interest was the number of animals with a wound tumor. Meta-regression was used to assess whether heterogeneity was explained by study level covariates (animal model, study size, CDP pressure, duration, and evaluated time). Twenty randomized control studies involving 1,229 animals were included. Wound recurrence was not significant in the laparoscopic surgery (LP) vs. gasless laparoscopic surgery (GLP) subgroups [odds ratio (OR), 2.23; 95 % confidence interval (CI), 0.90-5.55; P = 0.08) or the LP vs. laparotomy (LA) subgroups (OR, 0.97; 95 % CI, 0.31-3.00; P = 0.08). Overall postoperative wound recurrence results were not significantly different between the study groups and controls (OR, 1.47; 95 % CI, 0.74-2.92; P = 0.28). A meta-regression analysis showed that the outcome was not correlated with the covariates (animal model: P = 0.82; evaluated time: P = 0.30; pressure of CDP: P = 0.12; duration time: P = 0.80). Current evidence suggests that CDP does not enhance wound metastases following laparoscopic abdominal tumor surgery. Additional large sample, well-designed, randomized, controlled trials are needed to further confirm whether CDP duration in laparoscopic abdominal tumor surgery significantly enhances wound recurrence.

Camera-port site metastasis of a renal-cell carcinoma after robot-assisted partial nephrectomy

BACKGROUND AND PURPOSE

Port-site metastasis (PSM) is a rare complication of laparoscopic intervention in urologic malignancies. Of the greater than 50 reported cases of PSM in the urologic oncology literature, only 9 have occurred after surgery for renal-cell carcinoma (RCC). We report a 10th instance of RCC metastasis-in this case to the camera-port site after robot-assisted partial nephrectomy (RAPN). To our knowledge, this case is the first reported PSM of RCC after RAPN.

PATIENT AND METHODS

A 68-year-old man underwent an uncomplicated right RAPN for a 4-cm right renal mass (stage T1aN0M0). Five months later, he was found to have metastatic disease with an isolated peritoneal recurrence at the camera-port site. Biopsy of the lesion confirmed RCC, and the lesion was surgically resected. A comprehensive MEDLINE search for all published studies of port-site recurrences after laparoscopic renal surgery for RCC was performed.

RESULTS

Nine cases of PSM after successful laparoscopic radical or partial nephrectomy for locally confined RCC have been reported. Proposed etiologic factors for port-site recurrence include biologic aggressiveness of the tumor, patient immunosuppression, local wound factors, and technique-related factors. We report an unusual case of PSM to a camera port that was not used for specimen manipulation or extraction.

CONCLUSION

PSM after laparoscopic renal surgery for RCC is a rare occurrence. Our case, in which PSM occurred without specimen bag rupture or extraction through the port in question, highlights the importance of local and systemic factors in contributing to PSM occurrence. We also demonstrate that when PSM is the only site of disease recurrence, it can be successfully managed with minimally invasive surgical resection.

Port-site metastasis after laparoscopic surgery for urological malignancy: forgotten or missed

Purpose. Port-site metastasis has been a concern with the common use of laparoscopy in urologic oncology. We conducted this study to provide a review of port-site metastases reported after the laparoscopy in managing urologic malignancies, possible contributing factors and preventative measures. Materials and Methods. An electronic search of MEDLINE using the combined MESH key words “port-site metastasis” and “Urology”. Results. 51 articles addressing port-site metastasis after laparoscopic surgery for urolo¬gical malignancy were identified. Conclusion. Port-site metastasis after laparoscopic surgery for urolo¬gical malignancy is rare. The incidence is comparable to the rate for surgical wound metastases.

Port site metastases

PURPOSE OF REVIEW

The aim of this article is to provide an overview of the incidence, pathophysiology, risk factors and possible methods of reducing the risk of port site metastases following uro-oncological procedures.

RECENT FINDINGS

To our knowledge, 28 cases of port site metastasis have been reported in the urologic literature. There has been an increased interest in the use of intraperitoneal instillation of various tumoricidals in order to reduce the risk of port site seeding.

SUMMARY

The risk of port site metastases remains low, provided that surgeons rigorously adhere to the principles of oncological surgery.

Port-Site Metastasis after Laparoscopic Partial Nephrectomy: Case Report and Literature Review

Local recurrence and port-site metastasis remain a concern in urologic laparoscopic oncologic surgery. Portsite recurrence of renal-cell carcinoma after retroperitoneal and transperitoneal radical nephrectomy has been well documented. We report the first case of a port-site metastasis secondary to a partial nephrectomy and perform a literature review of this subject.

Port site metastases in urological laparoscopic surgery

PURPOSE

Laparoscopic surgery is rapidly gaining widespread acceptance among urologists, including extensive application in malignant conditions. However, untoward occurrences of port site metastases have not eluded to urological applications. This up-to-date review on port site metastases in urology delineates possible contributing factors and describes techniques to prevent it.

MATERIALS AND METHODS

We comprehensively reviewed published experimental and clinical studies with special emphasis on the incidence, pathophysiology and prevention of port site metastases.

RESULTS

Nine cases of port site metastases after urological laparoscopy have been described in clinical and experimental studies. Etiological factors include natural malignant disease behavior, host immune status, local wound factors, laparoscopy related factors such as aerosolization of tumor cells (the use of gas, type of gas, insufflation and desufflation, and pneumoperitoneum) and sufficient technical experience of the surgeons and operating team (adequate laparoscopic equipment, skill, minimal handling of the tumor, surgical manipulation and wound contamination during instruments change, organ morcellation and specimen removal).

CONCLUSIONS

Port site metastases is a multifactorial phenomenon with an as yet undetermined incidence. The problem is influenced to some extent by surgeon and operating team experience and, therefore, it could be partially prevented. The suggested preventive steps are avoiding laparoscopic surgery when there are ascites, trocar fixation to prevent dislodgment, avoiding gas leakage along and around the trocar, sufficient technical readiness of the operating team (adequate laparoscopic equipment and technique, minimal handling and avoiding tumor boundary violation of the tumor), using a bag for specimen removal, placing drainage when needed before desufflation, povidone-iodine irrigation of instruments, trocars and port site wounds, and suturing 10 mm. and larger trocar wounds.