Combination therapy inhibits tumor growth. (A) Combination PDT and L-IRI enhanced MIA PaCa-2 tumor volume reduction, determined by longitudinal ultrasound imaging. (B) Representative snapshots of MIA PaCa-2 tumors 3-weeks post-treatment. Scale bar=2cm. Tumor weights at this time showed the combination inhibited tumor growth. (C) Fold change in tumor volume 2-weeks post-treatment shows significantly lower volume in the combination group. (D) Combination PDT and L-IRI also enhanced AsPC-1 tumor volume reduction. (E) Representative snapshots of AsPC-1 tumors 3-weeks post-treatment. Scale bar, 2cm. Tumor weights at this time showed the combination slowed tumor growth. (F) A sustained and prolonged MIA PaCa-2 tumor growth inhibition was observed after two cycles of combination administered on 9 and 27 days post-implantation. Arrow indicates day of treatment. (*P<0.05,**P<0.01,***P<0.001, Kruskal–Wallis One-way ANOVA) (N=8–18)