Splicing Factor Pathway Is Rarely Mutated in Myeloid Blast Phase of PV with Dysmyelopoiesis and Ring Sideroblast
Bibliographic record
Abstract
Abstract Introduction: BP of PV presents with dyserythropoiesis, including ring sideroblasts, and bilineage dysplasia in most cases. Clonal evolution or acquisition of new cytogenetic clone(s) plays a critical role in progression to BP of PV. SF3B1 mutation is associated with 75% of MDS with ring sideroblasts (RS). We hypothesized that an increase in ring sideroblast counts is an early event in the BP evolution. We postulate that genomic lesions other than in splicing factors genes are implicated in RS development in PV during BP evolution. Methods: We identified all cases in the last 14 years (2004 - 2018) with a diagnosis of PV in the MDACC files. We collected demographic, clinical, morphological, cytogenetic, and NGS information from 61 patients who developed BP progression from PV. We did an assessment and scoring of all bone marrow (BM) samples available at BP evolution. Results: A total of 61/477 (13%) patients with diagnosis of BP of PV were identified. Median age at BP diagnosis was 67 yrs. (32-82). This included 34 (56%) men and 27 (44%) women. At BP presentation, median BM blast percentage was 28%; 51 (84%) patients had BM dysplasia; 35 patients (69%) with dyserythropoiesis, 22 (43%) cases showed bilineage dysplasia. At BP, 43 pts had complex CG, 9 were were normal karyotype, 3 had double and 5 had single abnormalities. Prussian blue stain for Iron evaluation was available in 54 patients (89%); 24 patients (44%) had 0% RS; 19 patients (35%) had 1-14% RS; and 11 pts (20%) had >15% RS. Mutation analysis for splicing factor was performed on 13 patients. Of these, 2 patients with >15% RS had SRSF2 mutation and 1 patient with 6% RS had SF3B1 mutation. The other patients were wild type for SF3B1, SRSF2, U2AF1 (5 patients: >15% RS, 2 patients: 1-14% RS and 3 patients: 0% RS). Twenty-four (39%) patients had BM available before the BP diagnosis; median time between first BM at MDACC and BP BM diagnosis was 35 months (range, 1-135). At Baseline BM assessment, median BM blast was 3%; 13 (54%) patients had BM dysplasia. Prussian blue stain for Iron evaluation was available in 13 pts (55%): 10 pts (77%) had 0% RS and 3 pts (23%) had 1, 3, and 60% RS, respectively. To evaluate the level of RS during disease evolution we identified 10/26 pts who had at least 1 BM sample available between the first BM and the BP. 5/10 pts were in spent phase with increased blast, multilineage dysplasia and complex CG (RS: 6%, 25%, 0%, 1% and 50%) median time between samples 5 months. 4/10 pts had 1-4% blast, isolated dyserythropoiesis and normal diploid CG (RS: 12%, 5%, 2% and 0%). The median time between samples was 56 months. The last pt. had 0% blast, no dysplasia, del(20q) on CG and no RS. Pt. developed BP of PV 41 months after this follow up sample. Ten pts with PV chronic phase and were used as control group, median follow up of 14,5 yr. None of the patients had RS at baseline or at last follow up BM. Median time between samples 6 yrs. RS increase during PV evolution were statistically significant more frequent in pts who develop BP than in pts who remain in chronic phase of PV (7/10 vs. 0/10. P=0.003) Conclusion: Splicing factor gene mutation is infrequent in BP of PV despite the presence of dyserythropoiesis and frequent RS in 55% of patients. When present , RS may identify disease evolution and correlate with the disease phase of PV before BP. Dyserythropoiesis and the acquisition of RS is an early event BP of PV that precede other markers of disease progression like CG. Disclosures No relevant conflicts of interest to declare.
Fetched live from OpenAlex and de-inverted. Abstracts are not stored in this database: the inverted indexes are 8.6 GB of the frame’s 9.3 GB of text, and the host has 13 GB free.
How this classification was reachedexpand
Full frame machine prediction
Teacher imitationNot calibrated prevalence, not ground truth. Human validation pending. The Gemma side is a direct model label for every work in the frame, read from the title-only record. The Codex side is a classifier learned from the 10,348 direct Codex labels and calibrated to design-weighted sample rates; fields without enough sample support carry no Codex call. Candidate is the union of the two sides; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels.
Distilled classifier scores by category (both heads)
| Category | Codex | Gemma |
|---|---|---|
| Metaresearch | 0.000 | 0.001 |
| Meta-epidemiology (narrow) | 0.000 | 0.000 |
| Meta-epidemiology (broad) | 0.000 | 0.000 |
| Bibliometrics | 0.001 | 0.000 |
| Science and technology studies | 0.000 | 0.000 |
| Scholarly communication | 0.000 | 0.000 |
| Open science | 0.000 | 0.000 |
| Research integrity | 0.000 | 0.000 |
| Insufficient payload (model declined to judge) | 0.003 | 0.000 |
Machine scores (provisional)
The two teacher heads of the student model, read on this work. A score orders the frame for review; it never asserts a category, and the validation status ships verbatim with every row.
Baseline scores from an immature model (maturity gate not passed, 7 training rounds). Scores rank; they never assert a category.
score_only:v0-immature-baseline · verbatim from the scoring run: score_only means the number may rank works, and no category label ships from itClassification
machine, unvalidatedMachine predicted; a candidate call from one source (direct Gemma or distilled Codex), not a consensus.
How this classification was reached, model by model and score by score, is at the end of the page under "How this classification was reached".