Chemotherapeutic (cyclophosphamide) effects on rat breast tumor hemodynamics monitored by multi-channel NIRS

Jae G. Kim, Dawen Zhao, Ralph P. Mason, Hanli Liu

Research output: Chapter in Book/Report/Conference proceedingConference contribution

Abstract

We previously suggested that the two time constants quantified from the increase of tumor oxyhemoglobin concentration, Δ[HbO 2], during hyperoxic gas intervention are associated with two blood flow/perfusion rates in well perfused and poorly perfused regions of tumors. In this study, our hypothesis is that when cancer therapy is applied to a tumor, changes in blood perfusion will occur and be detected by the NIRS. For experiments, systemic chemotherapy, cyclophosphamide (CTX), was applied to two groups of rats bearing syngeneic 13762NF mammary adenocarcinomas: one group received a single high dose i. p. (200 mg/kg CTX) and the other group continuous low doses (20 mg/kg CTX i. p. for 10 days). Time courses of changes in tumor Δ[HbO 2] were measured at four different locations on the breast tumors non-invasively with an inhaled gas sequence of air-oxygen-air before and after CTX administration. Both rat body weight and tumor volume decreased after administration of high dose CTX, but continuous low doses showed decrease of tumor volume only. Baselines (without any therapy) intra- and inter-tumor heterogeneity of vascular oxygenation during oxygen inhalation were similar to our previous observations. After CTX treatment, significant changes in vascular hemodynamic response to oxygen inhalation were observed from both groups. By fitting the increase of Δ[HbO 2] during oxygen inhalation, we have obtained changes of vascular structure ratio and also of perfusion rate ratio before and after chemotherapy. The preliminary results suggest that cyclophosphamide has greatest effect on the well perfused tumor vasculature. Overall, our study supports our earlier hypothesis, proving that the effects of chemotherapy in tumor may be monitored non-invasively by using NIRS to detect changes of hemodynamics induced with respiratory challenges.

Original languageEnglish (US)
Title of host publicationProgress in Biomedical Optics and Imaging - Proceedings of SPIE
EditorsB. Chance, R.R. Alfano, B.J. Tromberg, M. Tamura, E.M. Sevick-Muraca
Pages282-292
Number of pages11
Volume5693
DOIs
StatePublished - 2005
EventOptical Tomography and Spectroscopy of Tissue VI - San Jose, CA, United States
Duration: Jan 23 2005Jan 26 2005

Other

OtherOptical Tomography and Spectroscopy of Tissue VI
CountryUnited States
CitySan Jose, CA
Period1/23/051/26/05

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Keywords

  • Breast Cancer
  • Cyclophosphamide
  • Hemodynamics
  • NIR Spectroscopy
  • Tumor vascular oxygenation

ASJC Scopus subject areas

  • Engineering(all)

Cite this

Kim, J. G., Zhao, D., Mason, R. P., & Liu, H. (2005). Chemotherapeutic (cyclophosphamide) effects on rat breast tumor hemodynamics monitored by multi-channel NIRS. In B. Chance, R. R. Alfano, B. J. Tromberg, M. Tamura, & E. M. Sevick-Muraca (Eds.), Progress in Biomedical Optics and Imaging - Proceedings of SPIE (Vol. 5693, pp. 282-292). [57] https://doi.org/10.1117/12.591423