Clinicopathological and molecular characteristics of extramedullary acute myeloid leukaemia

Abstract

Aims Myeloid sarcoma (MS) is a rare extramedullary neoplasm composed of immature myeloid precursor cells thought to be a unique clinical presentation of acute myeloid leukaemia (AML). Like AML, MS has a poor prognosis, but due to the rare nature of MS there are limited studies examining potential prognostic factors. We report our institutional experience, with the aim of investigating and establishing salient clinicopathological and molecular features of MS. Methods and results We retrospectively examined all clinicopathological and molecular data on MS patients between 2001 and 2017 from the University of Alabama at Birmingham (UAB) electronic medical records. The UAB electronic medical records were also reviewed and compared with the literature for other potential prognostic factors. Sixty‐three patients were included in the study. The median overall survival was 24 months in the group with normal karyotype and 12 months in patients with an abnormal karyotype. Conclusions We found that an abnormal karyotype was associated with a statistically significant worse prognosis.

Pancreatic Myeloid Sarcoma

“…The most frequently expressed antigens by MS include CD11c, CD13, CD33, CD34, CD43, CD45, CD56, CD68, CD117, lysozyme, and myeloperoxidase. Aberrant expression of B-cell or T-cell markers may also be observed [17][18][19]. Once diagnosed, it becomes fundamental to determine whether MS is occurring de novo or coinciding with a myeloid neoplasm.…”

“…Complex cytogenetics occur in about 17% of MS in nonleukemic patients compared with 39% of patients with MS arising in the setting of AML. Common genetic abnormalities include t(8,21) (q22;q22), inv (16), 11q23, t(9;11), t(8;17), t(8;16), t(8;17), t(1;11), monosomy 7, deletion of chromosomes 5q, 16q, and 20q, and trisomy 4, 8, and 11 [18]. Involvement of some particular extramedullary sites is associated with certain abnormalities, such as MS of the abdomen and inv (16) [15][16][17][18][19].…”

“…Despite the fact that isolated pancreatic MS can be treated with radiotherapy or surgical resection, AML-type remission induction chemotherapy is mandatory after resection of the isolated MS lesion. Otherwise, MS would recur [12,[15][16][17][18][19]. In addition, time to progression to acute leukemia has been shown to be longer in those treated with systemic chemotherapy as opposed to local radiotherapy or surgery [11].…”

<p>Urgent Chemotherapy Successfully Rescues a Near Death Patient of Acute Intracranial Hypertension Caused by Intracranial Myeloid Sarcoma</p>

“…Intracranial myeloid sarcomas are rare and account for about 3% of all extramedullary sarcomas. Myeloid sarcoma can be caused by AML, 3 chronic myeloid leukemia (CML), 4,5 chronic myelomonocytic leukemia (CMML), 6 and primary myelofibrosis (PMF). [7][8][9] It has been reported that intracranial myeloid sarcoma may originate from the superficial arachnoid vein wall and extend into the cerebrospinal fluid.…”

Tender subcubcutaneous plaques in a patient with acute myeloid leukemia

“…Given the patient’s history of malignancy, it is important to also consider both myeloid sarcoma, also known as chloroma, and leukemia cutis as potential causes of the patient’s skin findings. Myeloid sarcoma is a rare extramedullary neoplasm considered to be a unique presentation of AML in 2–8% of patients with this malignancy 3 . Nodules tend to be the most common initial presentation in cases with isolated dermatologic involvement 3 .…”