T.R. KI*^#, S. HIEN**, OUEDRAOGO ZOUNGRANA**, H. KONATÉ***, D. LOMPO***,               K. ADAMBOUNOU ****, M.  ZOUNGRANA*****

*Department of Medical Imaging, CHU Sourô Sanou, “Nazi Boni” University, Bobo-Dioulasso, Burkina Faso

**Ouagadougou Cancer Center, “Joseph Ki-Zerbo” University, Ouagadougou, Burkina Faso

***Department of Medical Imaging, CHU ”Sourô Sanou”, Bobo-Dioulasso, Burkina Faso

****Department of Medical Imaging, CHU Campus de Lomé, University of Lomé, Lomé, Togo

*****Renewable Thermal Energy Laboratory, ”Joseph Ki-Zerbo” University, Ouagadougou, Burkina Faso

Abstract. Breast cancer follow-up frequently relies on repeated thoraco-abdomino-pelvic (TAP) computed tomography (CT) scan, exposing patients to cumulative radiation doses. This prospective, single-center study, conducted at CHU ”Sourô Sanou” (Bobo-Dioulasso, Burkina Faso) in 47 patients followed for histologically confirmed breast cancer, evaluated the dosimetric and diagnostic value of a single-phase (portal-phase) TAP CT scan protocol compared with each patient’s standard multiphasic reference examination. The single-phase protocol gave an average effective dose of 15.53 ± 2.10 mSv, compared to 26.84 ± 6.40 mSv for the standard protocol, which corresponds to a dose reduction of 42.13 % (P < 0.001), with no patient exceeding the 20 mSv alert threshold. The image quality was rated satisfactory or excellent in over 95 % of the exams by two reviewers, with good to almost perfect agreement between observers, especially for liver metastases (kappa = 0.81), the main metastatic site in this group (40.42 % of metastatic cases). These results support adopting a single-phase portal protocol as the standard follow-up strategy for breast cancer, in line with the ALARA (As low as reasonably achievable) principle, while preserving diagnostic performance.

Key words: optimization, radiation, breast cancer, CT scan, Burkina Faso.

Corresponding author’s e-mail: medecinenucleaire.ceco@gmail.com