Regional lymph node metastasis from port site implants after laparoscopic surgery

Rectus Abdominis Muscle Resection for Abdominal Wall Recurrence of Mucinous Adenocarcinoma or Peritoneal Mesothelioma

Aims and Background

Diagnostic technologies which penetrate the abdominal wall in an attempt to definitively diagnose an intraabdominal malignancy by biopsy can contaminate the abdominal wall by cancerous cells. With follow-up these entrapped cancer cells may progress as an abdominal wall recurrence of the disease process. Frequently, laparoscopy is the definitive diagnostic study which results in the abdominal wall cancer progression.

Methods

We examined recurrences within the abdominal wall and attempted to establish a surgical approach to this problem which would maximize a functional result and minimize the incidence of disease persistence within the abdominal wall.

Results

Eighteen patients with abdominal wall recurrence were studied. Laparoscopy port sites resulted in the abdominal wall disease in eight patients, in four the recurrence was at a previous ostomy site, in three it was in a Pfannenstiel incision and in three it was in a McBurney incision site. All of these patients were treated by total resection of the rectus abdominis muscle. This resulted in a complete removal of visible disease that was dissecting along the fibers of the rectus abdominis muscle.

Conclusions

No patients required reoperation for abdominal wall hernia and mesh repair was not used in any of these patients. Disease control within the abdominal wall has been excellent.

More Reasonable Animal Model for Study the Effect of Pneumoperitoneum on Abdominal Tumor Cells

Background:

Many animal experimental studies showed that abdominal tumor cells will be widely spread during laparoscopic treatment and grow into metastases. These results are different from clinical observations. There is a hypothesis that too much tumor cells was injected in the animals lead to the results of theses bias. We aim to learn the difference of abdominal cavity volume between human body and the nude mice and to determine reasonable amount of tumor cells in the animal experiments.

Methods:

The insufflated CO₂ volume which represents the capacity of the abdominal cavity was recorded during laparoscopic process in 212 patients and 20 nude mice respectively, the relative volume of nude mice and human body was calculated. Based on data from the literature and this study , the amount of tumor cells in the animal experiments was determined. According to these data, we set up a new animal model and a traditional one respectively, and compared the rate of successful modeling and tumor formation between two animal models.

Results:

The intraperitoneal volumes of humans and nude mice were 3.01±0.36 L and 0.011±0.001 L respectively.The number of tumor cells that be uesd in animal should be approximately 0.26×10⁵ in terms of known data in human beings. Compared with the traditional animal model which formed a large number of intraperitoneal tumor metastasis, the new animal model was shows more moderately, and the rate of successful modeling was similar.

Conclusion:

In animal experiments, to simulate the clinical situation, about 0.26×10⁵ tumor cells should be inject in peritoneal cavity of the nude mice.

Early Oncologic Failure after Robot-Assisted Radical Cystectomy: Results from the International Robotic Cystectomy Consortium

PURPOSE

We sought to investigate the prevalence and variables associated with early oncologic failure.

MATERIALS AND METHODS

We retrospectively reviewed the IRCC (International Radical Cystectomy Consortium) database of patients who underwent robot-assisted radical cystectomy since 2003. The final cohort comprised a total of 1,894 patients from 23 institutions in 11 countries. Early oncologic failure was defined as any disease relapse within 3 months of robot-assisted radical cystectomy. All institutions were surveyed for the pneumoperitoneum pressure used, breach of oncologic surgical principles, and techniques of specimen and lymph node removal. A multivariate model was fit to evaluate predictors of early oncologic failure. The Kaplan-Meier method was applied to depict disease specific and overall survival, and Cox proportional regression analysis was used to evaluate predictors of disease specific and overall survival.

RESULTS

A total of 305 patients (22%) experienced disease relapse, which was distant in 220 (16%), local recurrence in 154 (11%), peritoneal carcinomatosis in 17 (1%) and port site recurrence in 5 (0.4%). Early oncologic failure developed in 71 patients (5%) at a total of 10 institutions. The incidence of early oncologic failure decreased from 10% in 2006 to 6% in 2015. On multivariate analysis the presence of any complication (OR 2.87, 95% CI 1.38-5.96, p = 0.004), pT3 or greater disease (OR 3.73, 95% CI 2.00-6.97, p <0.001) and nodal involvement (OR 2.14, 95% CI 1.21-3.80, p = 0.008) was a significant predictor of early oncologic failure. Patients with early oncologic failure demonstrated worse disease specific and overall survival (23% and 13%, respectively) at 1 and 3 years compared to patients who experienced later or no recurrences (log rank p <0.001).

CONCLUSIONS

The incidence of early oncologic failure following robot-assisted radical cystectomy has decreased with time. Disease related rather than technical related factors have a major role in early oncologic failure after robot-assisted radical cystectomy.

Port--site metastases following bariatric surgery

Morbid obesity is a huge problem of the twenty-first century, mostly treated by bariatric surgery. The authors report the case of a patient with port site metastases from an unknown rectal adenocarcinoma when bariatric surgery took place. Implants in the site of the subcutaneous access port to the band are problematic, particularly in patients with occult intra-abdominal malignancy. This case underlines the importance of preventive measures to avoid cell implant in port sites in benign such as malignant diseases.

Application of a solid tumor model to evaluate tumor recurrence after an open or laparoscopic rectal resection in rats

PURPOSE

We used a solid tumor model to evaluate the influence of laparotomy versus laparoscopy on tumor growth after curative resection for rectal cancer in rats.

METHODS

Colon tumor cells (DHD/K12/TRb) were administered intraperitoneally in 15 rats, which were used as solid tumor donors. Twenty-one days later, a 20-mg piece was then implanted in the rectal submucosa of the study rats (n=45). Animals were randomized into 3 groups for rectal resection either open or laparoscopic using either carbon dioxide (CO2) or helium for pneumoperitoneum. Autopsy took place 21 days after resection and tumor recurrence was evaluated.

RESULTS

Port-site metastasis was observed after laparoscopy with CO2 (1 animal) and helium (1), whereas intraperitoneal tumor growth was detected in 2 and 3 animals of these groups. No tumor recurrence was observed after open surgery.

CONCLUSIONS

Our solid tumor model is a novel neoplastic model that might simulate the clinical situation of an upper rectal carcinoma. It might be helpful to develop new protocols in studying solid tumor biology and different surgical procedures for cancer to address problematic issues in oncologic research.