ABSTRACT
BACKGROUND: The presence of >94% classical monocytes (MO1, CD14++/CD16-) in peripheral blood (PB) has an excellent performance for the diagnosis of chronic myelomonocytic leukemia (CMML). However, the monocyte gating strategy is not well defined. The objective of the study was to compare monocyte gating strategies and propose an optimal one. METHODS: This is a prospective, single center study assessing monocyte subsets in PB. First, we compared monocyte subsets using 13 monocyte gating strategies in 10 samples. Then we developed our own 10 color tube and tested it on 124 patients (normal white blood cell counts, reactive monocytosis, CMML and a spectrum of other myeloid malignancies). Both conventional and computational (FlowSOM) analyses were used. RESULTS: Comparing different monocyte gating strategies, small but significant differences in %MO1 and percentually large differences in %MO3 (nonclassical monocytes) were found, suggesting that the monocyte gating strategy can impact monocyte subset quantification. Then, we designed a 10-color tube for this purpose (CD45/CD33/CD14/CD16/CD64/CD86/CD300/CD2/CD66c/CD56) and applied it to 124 patients. This tube allowed proper monocyte gating even in highly abnormal PB. Computational analysis found a higher %MO1 and lower %MO3 compared to conventional analysis. However, differences between conventional and computational analysis in both MO1 and MO3 were globally consistent and only minimal differences were observed when comparing the ranking of patients according to %MO1 or %MO3 obtained with the conventional versus the computational approach. CONCLUSIONS: The choice of monocyte gating strategy appears relevant for the monocyte subset distribution test. Our 10-color proposal allowed satisfactory monocyte gating even in highly abnormal PB. Computational analysis seems promising to increase reproducibility in monocyte subset quantification.
Subject(s)
Leukemia, Myelomonocytic, Chronic , Monocytes , Humans , Monocytes/pathology , Leukemia, Myelomonocytic, Chronic/diagnosis , Leukemia, Myelomonocytic, Chronic/pathology , Prospective Studies , Reproducibility of Results , Flow Cytometry , Receptors, IgG , Lipopolysaccharide ReceptorsABSTRACT
BACKGROUND: Palbociclib is a specific inhibitor of cyclin-dependent kinases 4 and 6 that is approved for the treatment of advanced or metastatic breast cancer patients. Despite a good toxicity profile in pivotal trials, where asymptomatic neutropenia was the main adverse effect, its wider use in clinical practice may show less prevalent but serious toxicities. CASE PRESENTATION: Here, we describe a case of pneumonitis due to palbocicblib. A 57-year-old female with breast cancer with bone metastasis presented dyspnea at rest 3 months after beginning treatment with palbociclib and letrozole. Palbociclib-induced pneumonitis was considered the most probable cause after ruling out all alternatives, and the patient was successfully treated with steroids and showed complete remission. CONCLUSIONS: In summary, we present a well-documented case report of pneumonitis related to palbociclib. However, the mechanism of toxicity is still unknown, and there are as yet no reliable biomarkers to predict toxicity with cyclin-dependent kinase 4/6 inhibitors. In this case report, we alert physicians about new drugs that can provoke old toxicities.
