Introduction

We evaluated volumetric tumor measurements and computed tomography texture analysis as prognostic indicators in patients with advanced non-small-cell lung cancer when compared with the unidimensional tumor size measurements used in Response Evaluation Criteria in Solid Tumors (RECIST).

Patients and methods

In a retrospective review, computed tomography examinations in 77 patients with advanced non-small-cell lung cancer were evaluated before and after 2 cycles of chemotherapy. Baseline and changes in tumor diameter, volume, and texture were analyzed. Survival was analyzed with Cox regression analysis and Kaplan-Meier survival statistics.

Results

Cox regression analysis demonstrated that only change in tumor volume (exp(B) = 1.006; P = .02) and the initial sum of the largest target lesion diameters predicted survival (exp(B) = 1.013; P = .02). Kaplan-Meier statistics demonstrated that patients with an initial sum of the largest target lesion diameters less than 88 mm had median survival time of 587 days (95% confidence interval [CI], 269-905 days), compared with the survival of those with larger tumor burden of 407 days (95% CI, 235-579 days). Patients in whom tumor volume decreased by more than 29% had a median survival time of 622 days (95% CI, 448-796 days), compared with 305 days for those with less decrease (95% CI, 34-240 days).

Conclusion

This study demonstrates that change in lung tumor volume is a better marker of patient survival than change of unidimensional diameter measurements in our cohort. If confirmed in larger studies, this suggests that volumetry might improve clinical decision-making for individual patients and allow for faster assessment of new treatments.

The study of flow and particle dynamics in microfluidic cross-slot channels is of high relevance for lab-on-a-chip applications. In this work, we investigate the dynamics of a rigid spherical particle in a cross-slot junction for a channel height-to-width ratio of 0.6 and at a Reynolds number of 120 for which a steady vortex exists in the junction area. Using an in-house immersed-boundary-lattice-Boltzmann code, we analyse the effect of the entry position of the particle in the junction and the particle size on the dynamics and trajectory shape of the particle. We find that the dynamics of the particle depend strongly on its lateral entry position in the junction and weakly on its vertical entry position; particles that enter close to the centre show trajectory oscillations. Larger particles have longer residence times in the junction and tend to oscillate less due to their confinement. Our work contributes to the understanding of particle dynamics in intersecting flows and enables the design of optimised geometries for cytometry and particle manipulation.