Rare myeloid sarcoma with KMT2A (MLL)-ELL fusion presenting as a vaginal wall mass

Myeloid sarcoma as the only manifestation in a rare mixed lineage leukemia-fusion-driven acute myeloid leukemia: A case report

BACKGROUND

The mixed lineage leukemia (MLL)-eleven-nineteen lysine-rich leukemia (ELL) fusion gene is a rare occurrence among the various MLL fusion genes. We present the first case in which myeloid sarcoma (MS) was the only manifestation of adult MLL-ELL-positive acute myeloid leukemia (AML).

CASE SUMMARY

We report a case of a 33-year-old male patient who was admitted in June 2022 with a right occipital area mass measuring approximately 7 cm × 8 cm. Blood work was normal. The patient underwent right occipital giant subscalp mass excision and incisional flap grafting. Immunohistochemistry was positive for myeloperoxidase, CD43 and CD45 and negative for CD3, CD20, CD34, and CD56. The bone marrow aspirate showed hypercellularity with 20% myeloblasts. Flow cytometry showed that myeloblasts accounted for 27.21% of the nucleated cells, which expressed CD33, CD38, and CD117. The karyotype was 46, XY, t (11, 19) (q23; p13.1), -12, + mar/46, XY. Next-generation sequencing showed a fusion of MLL exon 7 to exon 2 of ELL. A diagnosis of MLL-ELL-positive AML (M2 subtype) with subcutaneous MS was made.

CONCLUSION

MLL-ELL-positive AML with MS is a rare clinical entity. Additional research is needed to elucidate the molecular mechanisms of the pathogenesis of MS.

Vulvovaginal myeloid sarcoma with massive pelvic floor infiltration: A case report and review of literature

BACKGROUND

Myeloid sarcoma (MS), including isolated and leukaemic MS, is an extramedullary myeloid tumour. MS can involve any anatomical site, but MS of the female genital tract is rare, with the ovaries and uterine body and cervix being the most commonly seen sites. Involvement of the vagina and vulva is extremely rare.

CASE SUMMARY

We report a rare case of MS with involvement of the vulva and vagina and massive infiltration of the pelvic floor. A 26-year-old woman presented with a vulvar mass, irregular vaginal bleeding and night sweats. Magnetic resonance imaging demonstrated an ill-defined, irregular vulvovaginal mass with massive involvement of the paravaginal tissue, urethra, posterior wall of the bladder, and pelvic floor. The signal and enhancement of the huge mass was homogeneous without haemorrhage or necrosis. Positron emission tomography/computed tomography showed high fluorodeoxyglucose uptake by the mass. Peripheral blood count detected blast cells. Vulvovaginal mass and bone marrow biopsies were performed, and immunohistochemistry confirmed the diagnosis of acute myeloid leukaemia (M-2 type, FAB classification) and vulvovaginal MS. The patient was treated with induction chemotherapy followed by allogeneic haematopoietic stem cell transplantation, and achieved complete remission. A systemic review of the literature on vulvovaginal MS was conducted to explore this rare entity’s clinical and radiological features.

CONCLUSION

Vulvovaginal MS is extremely rare. Diagnosis of vulvovaginal MS can only be confirmed histopathologically. Even though its clinical and imaging presentations are nonspecific, MS should be considered in the differential diagnosis of a newly developed T2-hyperintense, homogeneously enhanced vulvovaginal mass, especially in a patient with suspected haematological malignancy.

Primary splenic histiocytic sarcoma associated with hemophagocytic lymphohistiocytosis: A case report and review of literature of next-generation sequencing involving FLT3, NOTCH2, and KMT2A mutations

Background

Histiocytic sarcoma is a very rare monocyte/macrophage‐derived hematopoietic system tumor with a poor prognosis whose diagnosis is pathologically challenging due to its extreme rarity and histological overlap with various mimicking entities in which histiocytes also predominate.

Case

We report the case of a 33‐year‐old male patient with hemophagocytic lymphohistiocytosis, purpuric syndrome, and significant splenomegaly. The patient underwent splenectomy; subsequent macroscopic examination revealed a spleen weighing 2065 grams with hyperemic red pulp and multiple infarcts at the periphery. The histological and immunohistochemical study established a diagnosis of primary splenic histiocytic sarcoma with frequent hemophagocytosis. Next‐generation sequencing demonstrated mutations in FLT3, NOTCH2, and KMT2A, microsatellite stability, and a tumor mutational burden of 2 mut/Mb. The patient's condition deteriorated clinically from the appearance of the first symptoms and he died 6 months later from multi‐organ failure.

Conclusion

Primary splenic histiocytic sarcoma is one of the rarest tumors of the hematopoietic system. We report the first case with mutations in FLT3, NOTCH2, and KMT2A, and associated hemophagocytic lymphohistiocytosis.

The myeloid sarcoma treated by Venetoclax with hypomethylating agent followed by stem cell transplantation: rare case report

BACKGROUND

Myeloid sarcoma (MS) is a very rare condition, develops both in patients with other hematological neoplasms, and as isolated tumor. MS of the gynecologic tract is extremely rare. An available literature data about diagnosis and management of MS is summarized in the article. The role of chemotherapy, radiation therapy, surgery and bone marrow transplantation in the treatment is discussed. Polychemotherapy and allogeneic bone marrow transplantation were suggested to be the optimal treatment strategy of MS of the gynecological tract. The use of new targeted agents results in promising clinical data.

CASE PRESENTATION

We are presenting a rare clinical case of a MS of the uterine cervix with concomitant bone marrow involvement and describe all the peculiarities of the clinical course, diagnosis, and treatment. The patient received chemotherapy followed by allogeneic bone marrow transplantation. The pre-transplant therapy allowed us to perform allogeneic bone marrow transplantation with the deepest response possible: complete PET-negative and MRD-negative remission of the disease.

CONCLUSIONS

MS remains a subject of discussion regarding its diagnostic and therapeutic aspects. The use of novel targeting agents can be perspective option for patient with extramedullary disease.

Myeloid sarcoma

PURPOSE OF REVIEW

Myeloid sarcoma; also known as granulocytic sarcoma and chloroma, often occurs concomitantly with AML, and rarely without bone marrow involvement. In this article, we review the recent literature on myeloid sarcoma, focusing on treatment approach for this rare disease, and addressing the prognostic and therapeutic role of molecular and cytogenetic aberrations.

RECENT FINDINGS

Molecular testing and cytogenetics are important adjunct to conventional diagnostic methods. The significance of cytogenetic and molecular abnormalities in myeloid sarcoma is not completely established, but testing for targetable mutations on myeloid sarcoma cells is feasible, imperative, and may guide treatment decisions. Outcomes in myeloid sarcoma largely depend on the background of its development. Almost all patients with myeloid sarcoma eventually develop AML typically in a short period after its diagnosis; therefore, remission induction treatment using AML type chemotherapy has been the standard of care. Postremission therapy is controversial; allogenic SCT, radiotherapy or consolidation chemotherapy should be considered according to patient risk.

SUMMARY

Further research is required to understand the nature of myeloid sarcoma, and inclusion of patients with this condition in clinical trials should be considered to better identify the best diagnostic, prognostic, and therapeutic approach in managing this rare disease.