Short-term outcomes in older patients with peritoneal malignancy treated with cytoreductive surgery and HIPEC: Experience with 245 patients from a national centre.

BACKGROUND: Cytoreductive Surgery (CRS) combined with hyperthermic intraperitoneal chemotherapy (HIPEC) is increasingly accepted as the optimal management of selected patients with peritoneal malignancy. There is limited published evidence on outcomes in older patients treated by this complex therapeutic strategy. METHODS: A retrospective review of a prospective database of all patients who underwent CRS with HIPEC in a single institution over seven years. A comparative analysis of outcomes in patients under 65 undergoing CRS and HIPEC with patients ≥65 years was performed. The key endpoints were morbidity, mortality, reintervention rate and length of stay in the high dependency/intensive care (HDU/ICU) units. RESULTS: Overall, 245 patients underwent CRS and HIPEC during the study period, with 76/245 (31%) ≥65 years at the time of intervention. Tumour burden measured by the peritoneal carcinomatosis index (PCI) score was a median of 11 for both groups. Median length of hospital stay in the ≥65-year-old group was 14.5 days versus 13 days in the <65-year-old group (∗p = 0.01). Patients aged ≥65-years spent a median of one more day in the critical care unit ∗(p = 0.001). Significant morbidity (Clavien-Dindo ≥ Grade IIIa) was higher in the ≥65-year than the <65-year group (18.4% versus 11.2%). There were no perioperative deaths in the ≥65-year group. CONCLUSION: This study demonstrates higher perioperative major morbidity in ≥65-year group, but with low mortality in patients undergoing CRS/HIPEC for disseminated intraperitoneal malignancy. This increased morbidity does not translate into higher rates of re-interventions and highlights the importance of optimal patient selection.

Cytoreductive surgery and hyperthermic intraperitoneal chemotherapy for colorectal peritoneal metastases: outcomes from a national centre in the current era.

BACKGROUND: Multimodal therapy incorporating cytoreductive surgery (CRS) and hyperthermic intraperitoneal chemotherapy (HIPEC) improve survival for selected patients with colorectal peritoneal metastases (CPMs). Many countries have centralised management of these patients, aiming to improve outcomes. There is ongoing debate on the need for and complications associated with HIPEC administration. We report indications and outcomes after CRS/HIPEC treated in a national centre in the modern era. METHODS: A retrospective review of all CPM patients who underwent CRS and HIPEC since the initiation of an Irish national program in 2013. The primary endpoint was the overall survival associated with CRS/HIPEC. RESULTS: During the study period (April 2013-June 2020), 123 patients proceeded to planned CRS/HIPEC for CPM. Median age was 58 (IQR 47-67) and 55 patients (44.7%) were male. In 65 patients (52.8%), CPM was synchronous. In 7/123 (5.8%), disease was unresectable. The median peritoneal cancer index (PCI) was 10 (IQR 5-17). Overall, 104/123 (84.5%) underwent a complete cytoreduction (CC0/CC1). Thirteen out of 123 (10.5%) patients also had a synchronous liver resection. Forty out of 123 (32.5%) patients had adverse pathological features (poorly differentiated or signet ring cells). The median survival in patients after CC0, CC1 and CC2/3 resection was 50, 18 and 11 months respectively (*p = < 0.0001, Log-rank Mantel-Cox). In total, 14/123(11.4%) had a major post-operative complication and 4/123 (3.3%) required re-operation. There was one (0.8%) post-operative death. The median length of stay was 14 days (IQR 9-19). CONCLUSION: This study reports encouraging outcomes in patients with CPM undergoing CRS and HIPEC, especially when complete cytoreduction is achieved.

Gold nanowire electrodes in array: simulation study and experiments.

Recent developments in nanofabrication have enabled fabrication of robust and reproducible nanoelectrodes with enhanced performance, when compared to microelectrodes. A hybrid electron beam/photolithography technique is shown that permits discrete gold nanowire electrode arrays to be routinely fabricated at reasonable cost. Fabricated devices include twelve gold nanowire working electrode arrays, an on-chip gold counter electrode and an on-chip platinum pseudo reference electrode. Using potential sweep techniques, when diffusionally independent, these nanowires exhibit measurable currents in the nanoAmpere regime and display steady-state voltammograms even at very high scan rates (5000 mV s(-1)) indicative of fast analyte mass transport to the electrode. Nanowire electrode arrays offer the potential for enhancements in electroanalysis including increased signal to noise ratio and increased sensitivity while also allowing quantitative detection at much lower concentrations. However, to achieve this goal a full understanding of the diffusion profiles existing at nanowire arrays is required. To this end, we simulate the effects of altering inter-electrode separations on analyte diffusion for a range of scan rates at nanowire electrode arrays, and perform the corresponding experiments. We show that arrays with diffusionally independent concentration profiles demonstrate superior electrochemical performance compared to arrays with overlapping diffusion profiles when employing sweep voltammetric techniques. By contrast, we show that arrays with diffusionally overlapping profiles exhibit enhanced performance when employing step voltammetric techniques.