New stem cell transplant approach aims to tame deadly bone marrow cancer

Copied word for word from the study's registry entry, so the wording is the study team's rather than ours.

Inclusion Criteria: * Diagnosis of primary of secondary myelofibrosis with transplant indication by Dynamic International Prognostic Scoring System (DIPSS)-plus (\> intermediate-1) * Patients \>= age 50 must have a comorbidity score (hematopoietic cell transplant-comorbidity index \[HCT-CI\]) \< 4 (Sorror) * Patients can be in chronic phase (CP) with bone marrow (BM) blast count =\< 15% as long as no evidence of disease acceleration per principal investigator (PI) and treating physician's opinion or after progression to acute myeloid leukemia (AML) and achieved =\< 5% BM blasts (morphologic complete remission \[CR\] prior to transplant) * Lack of an human leukocyte antigen (HLA) matched donor or need to proceed fast to transplantation when a patient does not have an immediately available matched unrelated donor (typed by high-resolution in the registry) * Performance status \>= 70% (Karnofsky); patients \> 50 years should have adequate cognitive function; any concerns regarding cognitive function should be addressed by a geriatrician/neurologist * Alanine aminotransferase (ALT)/aspartate aminotransferase (AST)/bilirubin =\< 5 X upper limit of normal (ULN) * Measured creatinine clearance \> 60 mls/min * Left ventricular ejection fraction (LVEF) \>= 50% * Corrected carbon monoxide diffusing capability (DLCOc) \>= 50% * No active infections * Prior treatment with JAK2 inhibitor therapy is not excluded; a JAK2 inhibitor will need to be stopped 1-2 days prior to starting conditioning regimen * DONOR: Documented informed consent per local, state and federal guidelines * DONOR: Genotypically haploidentical as determined by HLA typing * Preferably a non-maternal HLA haploidentical relative due to data of high incidence of graft failure with use of maternal HLA haploidentical cells * Eligible donors include biological parents, siblings or half-siblings, children, or cousins in rare instances * DONOR: Absence of pre-existing donor-specific anti-HLA antibodies (DSA) in the recipient; Patients with pre-existing DSA could undergo desensitization per City of Hope (COH) standard operating procedures \[SOP\] and should have DSA \< MFI of 2000 prior to conditioning at discretion of PI * DONOR: Infectious disease screening performed within 30 days prior to stem cell mobilization per federal guidelines and is: * Seronegative for HIV 1+2 antibody (Ab) and/or HIV polymerase chain reaction (PCR), human T-cell leukemia virus (HTLV) I/II Ab, hepatitis B virus surface antigen (HBsAg), hepatitis B virus surface antibody (HBcAb), hepatitis C virus (HCV) Ab * Negative rapid plasma reagin (RPR) for syphilis * DONOR: Women of childbearing potential (WOCBP): Urine pregnancy testing performed within 7 days prior to stem cell mobilization * DONOR: Is approved and completed evaluation prior to recipient initiation of the preparative regimen per institutional guidelines Exclusion Criteria: * Evidence of severe portal hypertension with evidence of decompensation either with bleeding varices, large volume ascites, or hepatic encephalopathy * In a bone marrow biopsy 4 weeks prior to start of conditioning on study: * \> 15% bone marrow blasts at transplant if no history of AML and per PI and treating physician's opinion of disease acceleration * \> 5% if had previous progression to AML * Human immunodeficiency virus (HIV) positive; active hepatitis B or C * Patients with active infections; the PI is the final arbiter of the eligibility * Patients with evidence of severe pulmonary hypertension by echocardiogram and confirmed by a subsequent right side cardiac catheterization pre-enrollment * Liver cirrhosis * Prior central nervous system (CNS) involvement by tumor cells * History of another primary malignancy that has not been in remission for at least 3 years (the following are exempt from the 3-year limit: non-melanoma skin cancer, fully excised melanoma in situ \[stage 0\], curatively treated localized prostate cancer, and cervical or breast carcinoma in situ on biopsy or a squamous intraepithelial lesion on papanicolaou \[PAP\] smear) * Positive beta human chorionic gonadotropin (HCG) test in a woman with child bearing potential defined as not post-menopausal for 12 months or no previous surgical sterilization * Noncompliance - inability or unwillingness to comply with medical recommendations regarding therapy or follow-up, including smoking tobacco * DONOR: Has undergone solid organ, stem cell, bone marrow or blood transplantation * DONOR: Receiving any investigational agents, or concurrent biological, chemotherapy, immunosuppression or radiation therapy * DONOR: Active infection * DONOR: Thrombocytopenia \< 150,000 cells /mm\^3 at baseline evaluation * DONOR: Sero-positive for HIV-1 \& 2 antibody, HTLV-I \& II antibody, hepatitis B virus (HBV) and HCV * DONOR: Medical or physical reason which makes the donor unlikely to tolerate or cooperate with growth factor therapy and leukapheresis * DONOR: Factors which place the donor at increased risk for complications from leukapheresis or G-CSF therapy * DONOR: WOCBP: Pregnant or =\< 6 months breastfeeding