Mehmet Erdogan, Aykut Recep Aktas, Sevim Sureyya Cerci, Murat Kocer, Celal Cerci, Hasan Erol Eroglu

DOI: http://dx.doi.org/10.15379/2408-9788.2016.03.01.03

Published: 17 March 2016

Purpose: To evaluate the response to therapy with PET-CT in metastatic colorectal cancer patients treated with Bevacizumab and chemotherapy.

Methods: Twenty-two patients with metastatic colorectal cancer that were treated with bevacizumab and 6 cycles of chemotherapy were evaluated by whole-body PET-CT scan before and after the treatment in accordance with the European Organization for Research and Treatment of Cancer criteria.

Results: While 31.8% of patients responded to treatment (complete response + partial response), 68.2% did not respond to treatment (stable disease + progressive disease). The mean hepatic, extra hepatic, abdomen, lung and bone metastases SUVmax values were higher after treatment in comparison to the pre-treatment values. There was an increase in SUVmax values in those who did not respond to the treatment, while a decrease was observed in those who responded to the treatment. Survival was significantly increased in all patients that responded to the treatment. The difference in terms of gender, histological subtype, histological grade, primary tumor location, presence of metastases in regional lymph nodes and liver at the time of diagnosis or the response to the treatment was not statistically significant.
Conclusions: In this study we detected metabolic response before anatomical response with PET-CT in one third of metastatic colorectal cancer patients treated with Bevacizumab and chemotherapy. This finding suggests that PET-CT may be used as a measure to follow therapy response and predict the prognosis in metastatic colorectal cancer patients.

Metastatic colorectal cancers, Bevacizumab, Chemotherapy, Response to therapy, PET-CT.