Influence of Extraperitoneal Metastases on the Curative-Intent Management of Colorectal Peritoneal Metastases.

BACKGROUND: Selected patients with colorectal cancer peritoneal metastasis (CRPM) and extraperitoneal disease could be treated radically with a multimodal approach combining complete cytoreductive surgery, thermoablation, radiotherapy, and systemic and intraperitoneal chemotherapy. The impact of extraperitoneal metastatic sites (EPMS) in this setting remains unclear. PATIENTS AND METHODS: Patients with CRPM undergoing complete cytoreduction in 2005-2018 were grouped in: peritoneal disease only (PDO), one EPMS (1 + EPMS), two or more EPMS (2 + EPMS). A retrospective analysis compared overall survival (OS) and postoperative outcomes. RESULTS: Of 433 patients, 109 had 1 + EPMS and 31 had 2 + EPMS. Overall, 101 patients had liver metastasis, 19 lung metastasis, and 30 retroperitoneal lymph node (RLN) invasion. The median OS was 56.9 months. There was no significant OS difference between PDO and 1 + EPMS groups (64.6 and 57.9 months, respectively), whereas OS was lower in the 2 + EPMS group (29.4 months, p = 0.005). In multivariate analysis, 2 + EPMS [hazard ratio (HR) 2.86, 95% confidence interval (CI) 1.33-6.12, p = 0.007], Sugarbaker's Peritoneal Carcinomatosis Index (PCI) > 15 (HR 3.86, 95% CI 2.04-7.32, p < 0.001), poorly differentiated tumors (HR 2.62, 95% CI 1.21-5.66, p = 0.015), and BRAF mutation (HR 2.10, 95% CI 1.11-3.99, p = 0.024) were independent poor prognostic factors, while adjuvant chemotherapy was beneficial (HR 0.33, 95% CI 0.20-0.56, p < 0.001). Patients with liver resection did not show higher severe complication rates. CONCLUSION: In patients with CRPM selected for a radical surgical approach, limited extraperitoneal disease involving one site, notably the liver, does not seem to significantly impair postoperative results. RLN invasion appeared as a poor prognostic factor in this population.

Surfalize: A Python Library for Surface Topography and Roughness Analysis Designed for Periodic Surface Structures.

Surface roughness measurement is an integral part of the characterization of microtextured surfaces. Multiple established software packages offer the calculation of roughness parameters according to ISO 25178. However, these packages lack a specific set of features, which we hope to address in this work. Firstly, they often lack or have limited capabilities for automated and batch analysis, making it hard to integrate into other applications. Secondly, they are often proprietary and therefore restrict access to some potential users. Lastly, they lack some capabilities when it comes to the analysis of periodic microtextured surfaces. Namely, common parameters such as the peak-to-valley depth, spatial period and homogeneity cannot be calculated automatically. This work aims to address these challenges by introducing a novel Python library, Surfalize, which intends to fill in the gaps regarding this functionality. The functionality is described and the algorithms are validated against established software packages or manual measurements.

Increasing Heat Transfer from Metal Surfaces through Laser-Interference-Induced Microscopic Heat Sinks.

With the increasing processing power of micro-electronic components and increasing spatial limitations, ensuring sufficient heat dissipation has become a crucial task. This work presents a microscopic approach to increasing the surface area through periodic surface structures. Microstructures with a periodic distance of 8.5 µm are fabricated via Direct Laser Interference Patterning (DLIP) on stainless steel plates with a nanosecond-pulsed infrared laser and are characterized by their developed interfacial area ratio. The optimal structuring parameters for increasing the surface area were investigated, reaching peak-to-valley depths up to 12.8 µm and increasing surface area by up to 394%. Heat dissipation in a natural convection environment was estimated by measuring the output voltage of a Peltier element mounted between a hot plate and a textured sample. The resulting increase in output voltage compared to an unstructured sample was correlated to the structure depth and developed interfacial area ratio, finding a maximum increase of 51.4%. Moreover, it was shown that the output voltage correlated well with the structure depth and surface area.