Quantitative Sensory Analysis of Peripheral Neuropathy Produced by Colorectal Cancer and its Exacerbation by Cumulative Dose of Oxaliplatin Chemotherapy

• Published in: Cancer research (Chicago, Ill.) Ill.), 2014-09, Vol.74 (21), p.5955-5962
• Main Authors: de Carvalho Barbosa, Mariana, Kosturakis, Alyssa K., Eng, Cathy, Wendelschafer-Crabb, Gwen, Kennedy, William R., Simone, Donald A., Wang, Xin Shelley, Cleeland, Charles S., Dougherty, Patrick M.
• Format: Article
• Language: English
• ISSN: 0008-5472; 1538-7445
• DOI: 10.1158/0008-5472.CAN-14-2060

The goal in this study was to determine the impact of colorectal cancer and cumulative chemotherapeutic dose on sensory function to gain mechanistic insight to the subtypes of primary afferent fibers damaged by chemotherapy. Patients with colorectal cancer underwent quantitative sensory testing (QST) before and then prior to each cycle of oxaliplatin. These data were compared to that from age- and sex-matched healthy volunteers. The patients showed significant subclinical deficits in sensory function prior to any therapy compared to healthy volunteers. Sensory deficits became more pronounced in patients with chemotherapy. Sensory deficits were most pronounced for modalities mediated by large Aβ myelinated fibers and unmyelinated C fibers whereas those modalities of sensation conveyed by thinly myelinated Aδ fibers appeared showed less sensitivity to chemotherapy. Patients with baseline sensory deficits went on to develop more symptom complaints during chemotherapy than those who had no baseline deficit. Patients who were re-tested 6 to 12 months following chemotherapy showed the most numbness and pain as well as the most pronounced sensory deficits. The pattern of effects on sensory function has clear mechanistic implications for the fibers types that are vulnerable to the toxicity of chemotherapy.