Bilateral proliferative retinopathy is a rare complication of chronic myeloid leukemia (CML) as a few case reports have been published to date. In this case report, a 32-year old diabetic female presented with history of bilaterally decreased vision. Ophthalmologic examination showed bilateral proliferative retinopathy (i.e., retinal detachment, vitreous hemorrhage, pre-retinal fibrosis and the presence of bilateral peripheral capillary dropout with multiple retinal sea fan neovascularization) for which panretinal laser photocoagulation and vitrectomy were planned. During the preoperative workup, complete blood count revealed hyperleukocytosis. Later on, the karyotype analysis identified Philadelphia chromosome, confirming the diagnosis of CML. Hence, it was an interesting case where bilateral proliferative retinopathy directed to the diagnosis of CML. Therefore, proliferative retinopathy may be the first presentation of CML.

Mastocytosis is a heterogeneous group of rare diseases related to the clonal, neoplastic proliferation of morphologically and immunophenotypically abnormal mast cells, that accumulate in one or more organ systems. Their pathophysiology is dominated by activating mutations in C-Kit (Stem Cell Factor receptor). Several pathological forms have been described ranging from isolated cutaneous mastocytosis affecting mainly children, to aggressive systemic mastocytosis described mainly in adults with bone marrow involvement. According to the WHO 2016 classification of hematological malignancies, systemic mastocytosis appear as a new entity of "myeloid neoplasms and acute leukemias" that combines cytology (abnormal mast cells) with other genetic and molecular criteria. We describe through this observation the practical side of hematological cytology in the diagnostic orientation of this serious, rare and underestimated pathology.