Introduction Cervical cancer is the 4^th most frequent cancer in women worldwide. In the Philippines, it is the 2nd most common cancer among women. For locally advanced cervical cancer (LACC), chemoradiotherapy is the standard of care and assessment of tumor response to treatment is significant. In developing countries, ultrasound plays an essential role for treatment monitoring. This study aims to evaluate the treatment response to concurrent chemoradiotherapy (CCRT) and brachytherapy among patients with LACC through the use of ultrasound.

Methods Patients histologically diagnosed with LACC were prospectively enrolled. Series of ultrasound examination was performed during: initial consult (T0), day 14-16 of chemoradiotherapy (T1), after CCRT (T2), and 4 weeks after brachytherapy (T3). The following parameters were evaluated: tumor size, doppler studies, involvement of pelvic/para-aortic lymph nodes, parametrial involvement and extension to the uterus/vagina. After the T3 ultrasound, treatment response was evaluated based on WHO response criteria and categorized to: Complete Response (CR), Partial Response (PR), Stable Disease (SD), Progression.

Results 32 patients were initially recruited. 11 were withdrawn due to different reasons and 21 were able to complete the study protocol. 90% had CR, while 10% demonstrated disease progression. Among patients with CR, significant changes were noted in the median tumor size, Doppler color score, lymph node involvement, parametrial involvement, and tumor extension to the uterus/vagina post CCRT and brachytherapy. Whereas, no significant changes among the different parameters were noted among the progression group.

Conclusion/Implications Chemoradiotherapy is effective in the management of LACC. Ultrasound is valuable and practical in the evaluation of treatment response.