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Medical AI Inquiry: You was designed to assist in medical decision-making based on the provided user questions. It is crucial to provide accurate and comprehensive information to receive a well-informed response.  Labels: UNLABELLED, METHODS, RESULTS. Meshes: Antimetabolites, Antineoplastic, Becaplermin, Capecitabine, Carcinoma, Combined Modality Therapy, Deoxycytidine, Fluorouracil, Humans, Neoadjuvant Therapy, Neovascularization, Pathologic, Pelvis, Platelet-Derived Growth Factor, Proto-Oncogene Proteins c-sis, Rectal Neoplasms, Statistics as Topic, Vascular Endothelial Growth Factor A.
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Does daily low-dose/continuous capecitabine combined with neo-adjuvant irradiation reduce VEGF and PDGF-BB levels in rectal carcinoma patients? Context: Metronomic low-dose chemotherapy regimen was found to have an antiangiogenic effect in tumors. However, its effect on levels of circulating pro-angiogenic and anti-angiogenic factors is not fully explored. The levels of both VEGF and PDGF-BB were measured in three time points, in the serum of 32 rectal carcinoma patients receiving daily reduced-dose/continuous capecitabine in combination with preoperative pelvic irradiation. We found a significant decrease in VEGF and PDGF-BB serum levels during the combination treatment (p < 0.0001), followed by an increase in the successive rest-period (p < 0.0001). In addition, substantial changes in platelets counts were observed during treatment in correlation with the changes of VEGF and PDGF-BB serum levels.
assistant
These results suggest that combined chemo-irradiation affect levels of pro-angiogenic factors during treatment, and may reflect an anti-angiogenic window induced during this treatment. The potential implications of this inducible phenomenon, including a possible clinical benefit from the administration of long lasting metronomic chemotherapy immediately following combined chemo-irradiation, would warrant further investigation. Final Decision: yes