Introduction/Background Locally advanced cervical cancer presents a challenge in the realm of oncology.Its multimodal treatment has demonstrated notable success in tumor control, yet concerns persist regarding the high rate of acute hematology toxicity leading to treatment disruption and affecting patient prognosis.

Our purpose is to determine the impact of the dose received in the bone marrow of the pelvic on the hematology toxicity in patients receiving concomitant radio-chemotherapy.

Methodology A retrospective study was conducted in the radiotherapy department of Salah Azaiez’s institution. The medical records of patients undergoing concurrent chemotherapy and intensity-modulated radiotherapy were reviewed. The baseline and weekly hematological parameters were collected. Pelvic bone marrow was retrospectively delineated and divided into 3 sites: whole pelvic, small pelvic and iliac crests. V20, V5 and mean dose were calculated.

Results 21 patients were included. The average age was 58.47. Sixty-six of the patients were treated with volumetric modulated arc therapy. Only three patients received a para-aortic irradiation.

Nine patients presented anemia superior to or equal to 2, only two presented leukopenia, 3 with neutropenia and only 2 patients presented a grade 3 thrombopenia.

The mean dose of the iliac crest was respected in all patients. Only 8 patients respected V95% of the little pelvis and 10 patients of the V65%. For the whole pelvic, the dosimetry constraint was respected only in three patients.

Conclusion The clinical benefit of pelvic active bone marrow protection needs to be further validated in randomized controlled trials.

Disclosures The authors declare no competing interests.