Effect of laparoscopy versus laparotomy on circulating tumor cells using isolation by size of epithelial tumor cells

Technical Insights into Highly Sensitive Isolation and Molecular Characterization of Fixed and Live Circulating Tumor Cells for Early Detection of Tumor Invasion

Circulating Tumor Cells (CTC) and Circulating Tumor Microemboli (CTM) are Circulating Rare Cells (CRC) which herald tumor invasion and are expected to provide an opportunity to improve the management of cancer patients. An unsolved technical issue in the CTC field is how to obtain highly sensitive and unbiased collection of these fragile and heterogeneous cells, in both live and fixed form, for their molecular study when they are extremely rare, particularly at the beginning of the invasion process. We report on a new protocol to enrich from blood live CTC using ISET^® (Isolation by SizE of Tumor/Trophoblastic Cells), an open system originally developed for marker-independent isolation of fixed tumor cells. We have assessed the impact of our new enrichment method on live tumor cells antigen expression, cytoskeleton structure, cell viability and ability to expand in culture. We have also explored the ISET^®in vitro performance to collect intact fixed and live cancer cells by using spiking analyses with extremely low number of fluorescent cultured cells. We describe results consistently showing the feasibility of isolating fixed and live tumor cells with a Lower Limit of Detection (LLOD) of one cancer cell per 10 mL of blood and a sensitivity at LLOD ranging from 83 to 100%. This very high sensitivity threshold can be maintained when plasma is collected before tumor cells isolation. Finally, we have performed a comparative next generation sequencing (NGS) analysis of tumor cells before and after isolation from blood and culture. We established the feasibility of NGS analysis of single live and fixed tumor cells enriched from blood by our system. This study provides new protocols for detection and characterization of CTC collected from blood at the very early steps of tumor invasion.

Recent advances and prospects in the isolation by size of epithelial tumor cells (ISET) methodology

Current technologies to identify and characterize circulating tumor cells (CTCs) and _ circulating tumor microemboli (CTMs) among hundreds of millions of leukocytes in the bloodstream can be classified into tumor-marker-dependent and -independent technology. Isolation by size of epithelial tumor cells (ISET) is a tumor-marker-independent technology, in which CTCs are isolated by filtration without use of tumor-associated markers, as a result of their large size relative to circulating blood leukocytes. ISET allows cytomorphological, immunocytological, and genetic characterization of CTCs and CTMs. It offers a number of advantages, including retention of cell morphology; non-antigen dependence; amenability of cells to further interrogation by immunolabeling, fluorescence in situ hybridization, and RNA/DNA analysis; ability to isolate CTMs; reliability. Therefore, morphological-analysis-based and antigen-independent ISET methodology can yield more accurate and objective characterization of epithelial-mesenchymal transition. We can evaluate efficacy of _chemotherapy and radiotherapy and other cancer-targeting therapies by using xenografts that are suitable models for mechanistic studies of ISET-isolated CTC/CTM biology. In addition, a new _ISET-based device could be designed to increase sensitivity to CTCs/CTMs greatly and reduce the number of CTCs/CTMs directly during the blood flow, thus decreasing the _possibility of tumor recurrence and metastasis while retaining normal blood cells. This article reviews recent advances and prospects in ISET methodology and provides new insights into ISET methodology, with important implications for the clinical management of cancer patients.

Role of laparoscopy to evaluate candidates for complete cytoreduction in advanced stages of epithelial ovarian cancer

The objective of this study was to evaluate the role of laparoscopy in selecting candidates for complete cytoreduction surgery in epithelial ovarian carcinoma. We performed an explorative laparoscopy in 15 women presenting with advanced ovarian carcinoma, and for whom the preoperative evaluation was considered unsatisfactory, to define the possibility of achieving a complete cytoreduction. We focused on three sites of carcinomatosis: bowel, liver pedicle, and right diaphragmatic dome. Laparoscopic evaluation was successful in all 15 patients. Four patients were considered to have unresectable carcinomatosis because of extensive involvement of the small bowel and therefore had no laparotomy. These women underwent neoadjuvant chemotherapy in the following 2 weeks. Eleven patients were considered to have resectable peritoneal carcinomatosis (PC). Ten women had no macroscopic residual tumor after surgery. A modified posterior exenteration was performed in five patients. The laparoscopic exploration had underestimated the liver pedicle involvement in two patients, but only one had an infracentimetric residual tumor after surgery. Laparoscopy is a reliable method of exploring PC in advanced-stage ovarian cancer. Laparoscopy may obviate the need for unnecessary laparotomy in many cases and may, therefore, contribute to a better quality of life for patients found to have unresectable disease.

Cœlioscopie et cancer en gynécologie : le point en 2005

All the surgical procedures, which may be required to treat a gynecologic cancer, can be performed endoscopically. However prospective randomized studies required to confirm the oncologic efficacy of the technique are still lacking in gynecology, whereas such studies are available in digestive surgery. Animal studies suggested that the risk of tumor dissemination in non traumatized peritoneum is higher after a pneumoperitoneum than after a laparotomy. Experimental studies also emphasized two points: the surgeon and the surgical technique are essential, all the parameters of the pneumoperitoneum may influence the postoperative dissemination. Changing these parameters we may, in the future, be able to create a peritoneal environment adapted to oncologic patients in order to prevent or to decrease the risks of peritoneal dissemination and/or of postoperative tumor growth. Until the results of prospective randomized studies become available, the preoperative selection of the patients and the surgical technique should be very strict. In patients with endometrial cancer, the laparoscopic approach should be reserved to clinical stage I disease, if the vaginal extraction is anticipated to be easy accounting for the volume of the uterus and the local conditions. In cervical cancer, the laparoscopic approach should be reserved to patients with favorable prognostic factors: stage IB of less than 2 cm in diameter. Laparoscopy is the gold standard for the surgical diagnosis of adnexal masses. But the puncture should be avoided whenever possible. The surgical treatment of invasive ovarian cancer should be performed by laparotomy whatever the stage. In contrast restaging of an early ovarian cancer initially managed as a benign mass, is a good indication of the laparoscopic approach. The laparoscopic management of low malignant potential tumors should include a complete staging of the peritoneum. Knowledge of the principles of endoscopy and of oncologic surgery is required. Teaching and diffusion of endoscopic oncological techniques are among the major challenges of gynecologic surgery within the next few years.

Retroperitoneoscopy-Assisted Cryoablation of Renal Tumors Using Multiple 1.5mm Ultrathin Cryoprobes: A Preliminary Report

OBJECTIVES

Laparoscopic cryoablation has recently been proposed as a minimally invasive nephron-sparing treatment for selected patients. We report on our experience with a retroperitoneoscopic technique using multiple ultrathin cryoprobes.

METHODS

Seven patients underwent retroperitoneoscopic renal cryoablation for solid renal masses. Mean tumor size on the CT scan was 2.6 (1.5-3.5) cm. A double freeze-thaw cycle of renal cryoablation was performed under real-time ultrasound monitoring using a total of six 1.5-mm cryoprobes simultaneously.

RESULTS

Cryoablation was technically successful in all patients without any need for conversion. Mean duration of surgery was 161 (130-195) minutes and mean blood loss was 107 (50-250) ml. Perioperative biopsy of the tumor confirmed renal cell carcinoma in four patients and angiomyolipoma in two patients; it was inconclusive in one case. Mean follow-up for 13.6 (4-22) months showed no evidence of residual tumor or recurrence.

CONCLUSIONS

Retroperitoneoscopy-assisted cryosurgical ablation using multiple ultrathin 1.5-mm cryoprobes is a minimally invasive treatment that is suitable to treat small renal tumors.