Therapy-related myeloid neoplasms with different latencies: a detailed clinicopathologic analysis

Therapy-Related Myeloid Neoplasms: Complex Interactions among Cytotoxic Therapies, Genetic Factors, and Aberrant Microenvironment

Therapy-related myeloid neoplasm (t-MN), characterized by its association with prior exposure to cytotoxic therapy, remains poorly understood and is a major impediment to long-term survival even in the era of novel targeted therapies due to its aggressive nature and treatment resistance. Previously, cytotoxic therapy-induced genomic changes in hematopoietic stem cells were considered sine qua non in pathogenesis; however, recent research demonstrates a complex interaction between acquired and hereditary genetic predispositions, along with a profoundly senescent bone marrow (BM) microenvironment. We review emerging data on t-MN risk factors and explore the intricate interplay among clonal hematopoiesis, genetic predisposition, and the abnormal BM microenvironment. Significance: t-MN represents a poorly understood blood cancer with extremely poor survival and no effective therapies. We provide a comprehensive review of recent preclinical research highlighting complex interaction among emerging therapies, hereditary and acquired genetic factors, and BM microenvironment. Understanding the risk factors associated with t-MN is crucial for clinicians, molecular pathologists, and cancer biologists to anticipate and potentially reduce its incidence in the future. Moreover, better understanding of the molecular pathogenesis of t-MN may enable preemptive screening and even intervention in high-risk patients.

Chronic myeloid leukemia during osimertinib treatment in a non-small cell lung cancer patient: A case report

Case summary

A 45-year-old man presented with a 4.0cm × 4.0cm mass in right lower lobe and a right lower lobectomy was performed. The pathological diagnosis from the right lower lobe mass was adenocarcinoma with an EGFR mutation in exon 21 (L858R). He chose osimertinib as postoperative adjuvant treatment. Eight months after the administration of osimertinib, leukocytosis was detected and we diagnosed the patient with chronic myeloid leukemia (CML). After the diagnosis was made, the patient started the treatment of flumatinib immediately, and treatment of osimertinib continued. After one month treatment, leukocytosis was completely relived. The patient was receiving treatment of osimertinib and flumatinib simultaneously with both lung cancer and leukemia well-controlled, and the side effects were tolerable.

Conclusion

Hemogram of non-small cell lung cancer (NSCLC) patients should be carefully monitored during EGFR-TKIs treatment. While there is a potential association between EGFR-TKIs and the development of hematologic abnormalities such as CML, more evidence is needed to clarify whether EGFR-TKIs have a leukemogenic effect. For patients with CML during EGFR-TKIs treatment, osimertinib combined with flumatinib may be an effective treatment modalities and the side effects can be tolerated.

Secondary hematological malignancies in patients with sarcoma: A single‑center retrospective study

The present retrospective study investigated the clinical features and prognosis of secondary hematological malignancies (SHMs) in patients with sarcoma at Korea Cancer Center Hospital (Seoul, South Korea). Patients who had been diagnosed with SHMs after having received treatment for sarcoma between January 2000 and May 2023 were enrolled. Clinical data were collected from the patients' medical records. Clinical characteristics were analyzed, including SHM incidence, type and prognosis. Of 2,953 patients with sarcoma, 18 (0.6%) were diagnosed with SHMs. Their median age at the time of sarcoma diagnosis was 39.5 (range, 9-72) years, and 74% (n=14) of these patients were male. The histological features of sarcoma varied, with osteosarcoma diagnosed in nine patients (50%). All patients with sarcoma underwent surgical treatment, and 16 (88.8%) received chemotherapy. The most common type of SHMs was acute myeloid leukemia (n=6; 33.3%), followed by myelodysplastic syndrome (n=5; 27.7%). The median latency period between the sarcoma diagnosis and SHM identification was 30 (range, 11-121) months. A total of 13 (72.2%) patients received treatment for the SHM. The median overall survival after SHM diagnosis was 15.7 (range, 0.4-154.9) months. The incidence of SHMs in sarcoma in the present study was consistent with that reported previously. The presence of SHMs was associated with a poor patient prognosis, especially if treatment for SHMs was not administered.

Therapy-selected clonal hematopoiesis and its role in myeloid neoplasms

Therapy-related myeloid neoplasms (t-MN) account for approximately 10-15% of all myeloid neoplasms and are associated with poor prognosis. Genomic characterization of t-MN to date has been limited in comparison to the considerable sequencing efforts performed for de novo myeloid neoplasms. Until recently, targeted deep sequencing (TDS) or whole exome sequencing (WES) have been the primary technologies utilized and thus limited the ability to explore the landscape of structural variants and mutational signatures. In the past decade, population-level studies have identified clonal hematopoiesis as a risk factor for the development of myeloid neoplasms. However, emerging research on clonal hematopoiesis as a risk factor for developing t-MN is evolving, and much is unknown about the progression of CH to t-MN. In this work, we will review the current knowledge of the genomic landscape of t-MN, discuss background knowledge of clonal hematopoiesis gained from studies of de novo myeloid neoplasms, and examine the recent literature studying the role of therapeutic selection of CH and its evolution under the effects of antineoplastic therapy. Finally, we will discuss the potential implications on current clinical practice and the areas of focus needed for future research into therapy-selected clonal hematopoiesis in myeloid neoplasms.