ESMO Asia Virtual Congress 2020

Abstract 346P

Background

Chemotherapy-induced neutropenia (CIN) is a main side effect in chemotherapy of breast cancer (BC) patients. It may lead to febrile neutropenia that requires hospitalization and antibiotic treatment resulting in increased cost and unfavourable outcome. Little is known about the incidence of CIN in Indonesia despite the fact that BC is the most prevalent malignancy. This study investigates the occurence of severe CIN and identify its associated risk factors.

Methods

We considered 123 newly-diagnosed BC patients without terminal conditions and multiple cormobidities from July 2018 to July 2019. All patients received a three-weekly adjuvant, neo-adjuvant, or palliative chemotherapy without primary prophylaxis of GCSF. We defined severe CIN as the condition where absolute neutrophil count <0.5x10⁹/L during any chemotherapy cycle. We evaluated the association of clinical, pathological, and treatment factors with the risk of CIN in a logistic regression methodology, adjusted for patients’ demography.

Results

In this cohort, 73% patients had experienced severe CIN at least once during their chemotherapy. The risk of severe CIN in the 2nd, 3rd, and 4th cycle did not differ from the 1st cycle. However, after the 5th cycle, the risk significantly increased (p values ≤ 0.001 up to the 8th cycle). Higher age, poor ECOG index, lower pre-treatment monocyte count, and palliative intention were associated with the increased risk of severe CIN, while diabetes comorbidity was associated with the decreased risk (p= 0.049, < 0.001, 0.022, 0.037, and 0.017, respectively).

Conclusions

We have identified some risk factors for increasing the risk of severe CIN. These factors can serve as a guidance to support care and recognize those at high risk.