Basal 18F-FDG PET/CT as a predictive biomarker of tumor response for neoadjuvant therapy in breast cancer / 18F-FDG PET/TC basal como biomarcador predictor de respuesta tumoral al tratamiento neoadyuvante en el cáncer de mama

Purpose. To explore the relation between tumor kinetic assessed by 18F-FDG PET and final neoadjuvant chemotherapy (NC) response within a molecular phenotype perspective. Material and Methods. Prospective study included 144 women with breast cancer. All patients underwent a dual-time point 18F-FDG PET/CT previous to NC. The retention index (RI), between SUV-1 and SUV-2 was calculated. Molecular subtypes were re-grouped in low, intermediate and high-risk biological phenotypes. After NC, all residual primary tumor specimens were histopathologically classified in tumor regression grades (TRG) and response groups. The relation between SUV-1, SUV-2 and RI with the TRG and response groups was evaluated in all molecular subtypes and in accordance with the risk categories. Results. Responder's lesions showed significant greater SUVmax compared to non-responders. The RI value did not show any significant relation with response. Attending to molecular phenotypes, statistical differences were observed with greater SUV for responders having high-risk molecular subtypes. Conclusion. Glycolytic tumor characteristics showed a significant correlation with NC response and dependence of risk phenotype (AU)

Objetivo. Estudiar la relación entre la cinética tumoral valorada por 18F-FDG PET y la respuesta final al tratamiento neoadyuvante (TN) bajo la perspectiva del fenotipo molecular. Material y métodos. Estudio prospectivo que incluye 144 mujeres con cáncer de mama. A todas las pacientes se les realizó una 18F-FDG PET/CT de doble fase previa al TN. El índice de retención (IR) entre el SUV-1 y el SUV-2 fue calculado. Los subtipos moleculares se agruparon en bajo, intermedio y alto riesgo. Tras el TN, los especímenes residuales tumorales se clasificaron histológicamente en grados de regresión tumoral (GRT) y grupos de respuesta. La relación entre el SUV-1, SUV-2 y el IR con los GRT y los grupos de respuesta se evaluó para todos los subtipos moleculares y las categorías de riesgo. Resultados. Las lesiones que experimentaron respuesta mostraron mayores valores de SUVmax comparadas con las no respondedoras. El IR no mostró ninguna relación significativa con la respuesta. De acuerdo con los fenotipos moleculares, se observaron diferencias significativas con mayores valores de SUV en los respondedores pertenecientes a los subtipos moleculares de alto riesgo. Conclusión. Las características glucolíticas tumorales mostraron una relación significativa con la respuesta al TN y dependencia del fenotipo de riesgo (AU)

Basal (18)F-FDG PET/CT as a predictive biomarker of tumor response for neoadjuvant therapy in breast cancer.

PURPOSE: To explore the relation between tumor kinetic assessed by (18)F-FDG PET and final neoadjuvant chemotherapy (NC) response within a molecular phenotype perspective. MATERIAL AND METHODS: Prospective study included 144 women with breast cancer. All patients underwent a dual-time point (18)F-FDG PET/CT previous to NC. The retention index (RI), between SUV-1 and SUV-2 was calculated. Molecular subtypes were re-grouped in low, intermediate and high-risk biological phenotypes. After NC, all residual primary tumor specimens were histopathologically classified in tumor regression grades (TRG) and response groups. The relation between SUV-1, SUV-2 and RI with the TRG and response groups was evaluated in all molecular subtypes and in accordance with the risk categories. RESULTS: Responder's lesions showed significant greater SUVmax compared to non-responders. The RI value did not show any significant relation with response. Attending to molecular phenotypes, statistical differences were observed with greater SUV for responders having high-risk molecular subtypes. CONCLUSION: Glycolytic tumor characteristics showed a significant correlation with NC response and dependence of risk phenotype.