Continuous manual agitation significantly improves temperature distribution during closed hyperthermic intraperitoneal chemotherapy: Results of a porcine model.

BACKGROUND: Debate persists regarding the need for shaking during hyperthermic intraperitoneal chemotherapy. Studies assessing the thermal behaviors of the perfusate throughout the abdomen during hyperthermic intraperitoneal chemotherapy are limited. METHODS: A closed hyperthermic intraperitoneal chemotherapy technique was performed in an institutional International Animal Care and Use Committee approved porcine model targeting a 41°C outflow temperature. Continuous temperature monitoring was conducted. Abdominal shaking was performed for 60 second intervals and temperatures were allowed to equilibrate without shaking between intervals. Temperature distributions and changes due to shaking were evaluated. These findings were validated against human subjects' data. RESULTS: The experimental procedure was conducted in 2 different animals and with 6 total shaking intervals assessed. Without shaking, temperatures were highly variable ranging between 38.0 to 42.2°C. Shaking the abdomen reduced the mean range of temperatures across all locations observed from 3.9°C to 0.8°C (P < .01). The locations of the most divergent temperatures varied based on perfusion cannula position. The point of minimum temperature heterogeneity was achieved in 28.3 (19.1-37.5) seconds. After shaking stopped, heterogeneity equal to the baseline measurements was seen on average within 25.7 (13.3-38.0) seconds. The outflow catheter differed from the system mean temperature by 1.4°C and from the coldest-reading probe by 2.8°C and outperformed the inflow catheter for all time points. With shaking these were significantly reduced to 0.4°C (P < .01) and 0.6°C (P < .01). The patient data mirrored that of the pig data. CONCLUSION: Shaking significantly reduces temperature variability within the abdomen during hyperthermic intraperitoneal chemotherapy, and significantly improves the ability of the outflow catheter to estimate internal temperatures.

Optimal perfusion chemotherapy: A prospective comparison of mitomycin C and oxaliplatin for hyperthermic intraperitoneal chemotherapy in metastatic colon cancer.

BACKGROUND: Peritoneal carcinomatosis of colorectal adenocarcinoma (CRC) origin is common and is the second-most frequent cause of death in colorectal cancer. There is survival benefit to surgical resection plus hyperthermic intraperitoneal chemotherapy (HIPEC) for patients with metastatic CRC. However, there remains controversy between oxaliplatin (Oxali) and mitomycin C (MMC), as the agent of choice. METHODS: A review of our 285 patients prospective HIPEC database from July 2007 to May 2018 identified 48 patients who underwent cytoreductive surgery plus HIPEC with MMC or Oxali. Patients were stratified based on preoperative and postoperative peritoneal cancer indices (PCI). The primary outcomes of survival and progression-free survival were compared. RESULTS: Type of HIPEC chemotherapy was not found to be predictive of overall survival. Preoperative PCI (P = .04), preoperative response to chemotherapy (P = .0001), and postoperative PCI (P = .05) were predictive for overall survival. CONCLUSIONS: MMC or Oxali based HIPEC chemotherapy are both safe and effective for the management of peritoneal only metastatic CRC. Both perfusion therapies should be considered with all patients receiving modern induction chemotherapy.

Should Sentinel Lymph Node Biopsy Be Performed for All T1b Melanomas in the New 8th Edition American Joint Committee on Cancer Staging System?

BACKGROUND: In the 8th edition of the American Joint Committee on Cancer melanoma staging system, the T1b category has been redefined based solely on thickness and ulceration. National Comprehensive Cancer Network guidelines recommend consideration of sentinel lymph node biopsy (SLNB) for all patients with T1b melanomas (0.8 to 1.0 mm thick). We hypothesized that the new staging system would lead to excessive use of SLNB in patients with non-ulcerated T1b melanomas with a low risk of positive sentinel lymph nodes. STUDY DESIGN: The National Cancer Database 2015 Melanoma Public Use File was used to select patients undergoing SLNB for thin T1 cutaneous melanoma from 2010 to 2015. Clinicopathologic risk factors for having a positive SLNB were evaluated. Univariable and multivariable logistic regression models and classification and regression tree analysis were performed to identify groups with high and low risk of positive SLNB. RESULTS: We selected patients undergoing SLNB without ulceration with thickness 0.75 to 1.04 mm, staged T1b in the new 8th edition American Joint Committee on Cancer by thickness criteria alone (6,894 patients). Independent risk factors for a positive sentinel lymph node were age 56 years or younger (odds ratio [OR] 1.74; 95% CI 1.38 to 2.17), thickness 1.0 vs 0.8 to 0.9 mm (OR 1.36; 95% CI 1.09 to 1.70), female sex (OR 1.36; 95% CI 1.09 to 1.69), and mitotic rate ≥1/mm2 (OR 2.01; 95% CI 1.54 to 2.64). Classification and regression tree analysis identified 2 groups based on age, mitotic rate, and thickness with a risk of positive SLNB <5%. These 2 groups made up 55% of T1b, nonulcerated melanoma patients who underwent SLNB. CONCLUSIONS: The new 8th edition American Joint Committee on Cancer melanoma staging system T1b category should not be used to determine use of SLNB in thin melanoma, as more than one half of T1b lesions without ulceration have a low risk of positive sentinel lymph nodes.