I have a 87 yr old male w/ Dementia, Prostate Cancer s/p radiation, HTN EC0G 3 who was referred for leukocytosis. WBC 24k, Hb 8.4, plt 256. Immature blasts on differential. Peripheral flow reported 17% myeloid blasts. Aberrant CD56. Relative increased basophils. MPN testing showed CALR Type 1 mutation. BM Biopsy reported: Moderate to severe fibrosis/osteosclerosis. but ?no increased blasts. Flow reported 9% blasts. Monocytes with partial co-expression of CD56. FISH: Gain of 3q MECOM signal w/o gain of RPN1. Cytogenetics only -Y. Pathologist final report was "suspected underlying myeloid neoplasm, no increased blasts. NGS requested from frozen tissue however pathologist said sample available is an issue. Requesting Quest LeukoVantage peripheral blood panel. Wanted to ask your thoughts about the diagnosis and treatment recommendations.
This seems to be a complex case both diagnostically and therapeutically. Regardless of the underlying myeloid neoplasm, 17% myeloid blasts in the peripheral blood does suggest acute leukemia in evolution. The CALR type 1 mutation is interesting especially since this is associated with a favorable prognosis in MPNs. I am perplexed why no blasts were detected on the BM biopsy and would be interested in what IHC stains were used (CD34, CD117, etc). I agree with your plan to send NGS from the peripheral blood since there are blasts in the peripheral blood. The leading diagnosis right now would be MPN in accelerated phase. This is a poor prognosis AML. Therapeutically, it does not seem like their performance status would allow for much in terms of therapies. You could offer single agent decitabine if they are able to tolerate this, although a palliative approach would also be appropriate. The addition of venetoclax in AML secondary to MPN has not proven to be effective.