Morphology and immunophenotyping issues in the integrated diagnosis of hematologic disorders of elderly patients

In the middle of the 19th century, when Bennett and Virchow were trying to decide whether “leucocythemia” or “leukemia” would be the proper word to describe the recently discovered chronic myelogenous leukemia (CML), life expectancy was steadily rising from around 40 years of age in the previous century, to finally reach 50 years in 1900. This is to say that many hematologic disorders were extremely rare at that time. Nowadays, a newborn baby may expect to live up to 100 years old.1 Among the myriad of challenges this perspective raises, that of an increase in chronic hematologic disorders is to be foreseen and in fact can already be perceived. Four major evolutions can be highlighted which will require the skill of trained morphologists and adapted flow cytometry studies, for integrated diagnoses and follow up, where cytogenetics has already an important place and where that of molecular and next generation sequencing (NGS) techniques will certainly find theirs. They are namely: i) nutritional deficiency-related and autoimmune disorders, mostly anemia;2 ii) chronic myeloproliferative/myelodysplastic or lymphoid neoplasms; iii) therapy-related secondary leukemia/lymphomas; and iv) follow up of long-term survivors.