Pharmacokinetics of mitomycin C after resection of peritoneal carcinomatosis and intraperitoneal chemohyperthermic perfusion

Starting a peritoneal carcinomatosis treatment program in a developing country: A prospective analysis

BACKGROUND

Cytoreductive surgery (CRS) plus hyperthermic intraperitoneal chemotherapy (HIPEC) has become a valuable treatment strategy for selected patients with peritoneal carcinomatosis (PC). In Chile, it is an emerging technique. The aim of this study is to describe our protocol and report our perioperative results.

METHODS

A prospectively maintained database for patients undergoing exploratory surgery for PC was reviewed. Eligible patients were selected using the peritoneal cancer index in correlation with the primary tumor. Patients underwent HIPEC using mitomycin C. Clinical data and postoperative results were analyzed.

RESULTS

Seventy-six patients underwent exploratory surgery. Most patients were female (55%) with a median age of 62 years (range, 25-83). Complete CRS and HIPEC were achieved in 53 patients. The most frequent primary tumor site was colon-rectum (49%). The median number of resected organs was 4 (range, 1-13). Overall 90-day incidence of major complications was 26%. After a median follow-up of 26 months, 44 patients (83%) in the resected group were alive with no evidence of disease.

CONCLUSIONS

The PC treatment program at our institution has been established in a safe manner, with acceptable morbidity comparable to high-volume centers. A comprehensive preoperative evaluation, careful patient selection, and a cohesive team are necessary for successful results.

Tailoring heated intraperitoneal mitomycin C for peritoneal metastases originating from colorectal carcinoma: a translational approach to improve survival

Background:

Patients with peritoneal metastases (PMs) originating from colorectal carcinoma (CRC) are curatively treated by cytoreductive surgery (CRS) and hyperthermic intraperitoneal chemotherapy (HIPEC) with mitomycin C (MMC). We aim to improve patient selection for HIPEC by predicting MMC sensitivity.

Methods:

The MMC sensitivity was determined for 12 CRC cell lines and correlated to mRNA expression of 37 genes related to the Fanconi anaemia (FA)–BRCA pathway, ATM–ATR pathway and enzymatic activation of MMC. Functionality of the FA–BRCA pathway in cell lines was assessed using a chromosomal breakage assay and western blot for key protein FANCD2. Bloom syndrome protein (BLM) was further analysed by staining for the corresponding protein with immunohistochemistry (IHC) on both CRC cell lines (n=12) and patient material (n=20).

Results:

High sensitivity correlated with a low BLM (P=0.01) and BRCA2 (P=0.02) at mRNA expression level. However, FA–BRCA pathway functionality demonstrated no correlation to MMC sensitivity. In cell lines, weak intensity staining of BLM by IHC correlated to high sensitivity (P=0.04) to MMC. Low BLM protein expression was significantly associated with an improved survival in patients after CRS and HIPEC (P=0.04).

Conclusions:

Low BLM levels are associated with high MMC sensitivity and an improved survival after HIPEC.

Validation and use of microdialysis for determination of pharmacokinetic properties of the chemotherapeutic agent mitomycin C - an experimental study

BACKGROUND

Mitomycin C is a chemotherapeutic agent used in the treatment of peritoneal surface malignancies, administered as hyperthermic intraperitoneal chemotherapy after cytoreductive surgery. Pharmacokinetic studies have been based on analyses of blood, urine and abdominal perfusate, but actual tissue concentrations of the drug have never been determined. Microdialysis is an established method for continuous monitoring of low-molecular substances in tissues, and in the present study microdialysis of mitomycin C was studied in vitro and in vivo.

METHODS

Using in vitro microdialysis, relative recovery was determined when varying drug concentration, temperature and perfusion flow rate. In vivo microdialysis was performed in rats to verify long-term stability of relative recovery in four compartments (vein, peritoneum, extraperitoneal space and hind leg muscle). Subsequently, intravenous and intraperitoneal bolus infusion experiments were performed and pharmacokinetic parameters were calculated.

RESULTS

In vitro, compatibility of mitomycin C and microdialysis equipment was demonstrated, and relative recovery was stable over an adequate concentration range, moderately increased by raising medium temperature and increased when flow rate was reduced, all according to theory. In vivo, stable relative recovery was observed over seven hours. Mitomycin C exhibited fast and even distribution in rat tissues, and equal bioavailability was achieved by intravenous and intraperitoneal infusion. The half-life of mitomycin C calculated after intravenous infusion was 40 minutes.

CONCLUSIONS

Mitomycin C concentration can be reliable monitored in vivo using microdialysis, suggesting that this technique can be used in pharmacokinetic studies of this drug during hyperthermic intraperitoneal chemotherapy.

Treatment of peritoneal carcinomatosis by cytoreductive surgery and intraperitoneal hyperthermic chemoperfusion (IHCP): postoperative outcome and risk factors for morbidity

BACKGROUND

Cytoreductive surgery with limited or extended peritonectomy associated with intraperitoneal hyperthermic chemoperfusion (IHCP) has been proposed for treatment of peritoneal carcinomatosis (PC) from abdominal neoplasms.

METHODS

Fifty-nine patients with PC from abdominal neoplasms underwent 61 treatments using this technique from January 2000 to August 2005. Surgical debulking, completed by partial or total peritonectomy, was performed in most cases. In 16 patients with positive peritoneal cytology without macroscopic peritoneal disease, IHCP was performed in order to prevent peritoneal recurrence. IHCP was carried out throughout the abdominopelvic cavity for 60 minutes using a closed abdomen technique. Intra-abdominal temperature ranged between 41 degrees C and 43 degrees C; mitomycin C (25 mg/mq) and cisplatin (100 mg/mq) were the anticancer drugs generally used, and they were administered with a flow rate of 700-800 ml/minute.

RESULTS

Mean hospital stay was 13 +/- 7 (range 7-49) days. Postoperative complications occurred in 27 patients (44.3%); of these, major morbidity was observed in 17 (27.9%). The most frequent complications were wound infection (9 cases), grade 2 or greater hematological toxicity (5 cases), intestinal fistula (5 cases), and pleural effusion requiring drainage (5 cases). Reoperation was necessary in 5 patients (8.2%). One patient with multiorgan failure died in the postoperative period (mortality rate: 1.6%). Multivariate analysis of several variables identified completeness of cancer resection (CCR-2/3 vs. CCR-0/1, relative risk: 9.27) and age (relative risk: 1.06 per year) as independent predictors of postoperative morbidity. Preliminary follow-up data indicate that survival probability may be high in patients with ovarian or colorectal cancer and low in patients with gastric cancer.

CONCLUSIONS

IHCP combined with cytoreductive surgery involves a high risk of morbidity, but postoperative complications could be resolved favorably in most cases with correct patient selection and adequate postoperative care. Tumor residual and advanced age significantly increase the risk of morbidity after this procedure.

Treatment of peritoneal carcinomatosis by cytoreductive surgery and intraperitoneal hyperthermic chemoperfusion (IHCP): postoperative outcome and risk factors for morbidity

BACKGROUND

Cytoreductive surgery with limited or extended peritonectomy associated with intraperitoneal hyperthermic chemoperfusion (IHCP) has been proposed for treatment of peritoneal carcinomatosis (PC) from abdominal neoplasms.

METHODS

Fifty-nine patients with PC from abdominal neoplasms underwent 61 treatments using this technique from January 2000 to August 2005. Surgical debulking, completed by partial or total peritonectomy, was performed in most cases. In 16 patients with positive peritoneal cytology without macroscopic peritoneal disease, IHCP was performed in order to prevent peritoneal recurrence. IHCP was carried out throughout the abdominopelvic cavity for 60 minutes using a closed abdomen technique. Intra-abdominal temperature ranged between 41 degrees C and 43 degrees C; mitomycin C (25 mg/mq) and cisplatin (100 mg/mq) were the anticancer drugs generally used, and they were administered with a flow rate of 700-800 ml/minute.

RESULTS

Mean hospital stay was 13 +/- 7 (range 7-49) days. Postoperative complications occurred in 27 patients (44.3%); of these, major morbidity was observed in 17 (27.9%). The most frequent complications were wound infection (9 cases), grade 2 or greater hematological toxicity (5 cases), intestinal fistula (5 cases), and pleural effusion requiring drainage (5 cases). Reoperation was necessary in 5 patients (8.2%). One patient with multiorgan failure died in the postoperative period (mortality rate: 1.6%). Multivariate analysis of several variables identified completeness of cancer resection (CCR-2/3 vs. CCR-0/1, relative risk: 9.27) and age (relative risk: 1.06 per year) as independent predictors of postoperative morbidity. Preliminary follow-up data indicate that survival probability may be high in patients with ovarian or colorectal cancer and low in patients with gastric cancer.

CONCLUSIONS

IHCP combined with cytoreductive surgery involves a high risk of morbidity, but postoperative complications could be resolved favorably in most cases with correct patient selection and adequate postoperative care. Tumor residual and advanced age significantly increase the risk of morbidity after this procedure.