NCMP-17. BEWARE: ALL POSTERIOR FOSSA MASSES IN CHILDREN ARE NOT BRAIN TUMORS
Bibliographic record
Abstract
Abstract INTRODUCTION Isolated Myeloid sarcoma (MS) of the central nervous system (CNS-MS) is a very rare presentation of Acute Myeloid Leukemia (AML). A 10-year-old boy with a two-week history of intermittent headaches was referred to the emergency department (ED) by an optometrist for evaluation of bilateral papilledema. Physical examination in the ED confirmed the presence of papilledema with no other abnormal neurologic findings. Emergent MRI of the brain showed an avidly homogeneously enhancing extra-axial dural based mass in the right posterior fossa measuring 4.8 cm (AP) x 3.2 cm (CC) x 4.6cm (T), with significant mass effect and peri-tumoral vasogenic edema. Neuro-surgery consultation was obtained and complete blood count (CBC) was normal except for the presence of 13% blasts with occasional Auer rods seen on the peripheral blood smear. Bone marrow aspirate demonstrated 56% myeloblasts; A diagnosis of AML with CNS-MS (CNS-3c) was made and the initial lumbar puncture (LP) was deferred due to the risk of CNS herniation. Induction chemotherapy was initiated as per protocol. A CT scan done two weeks later showed complete resolution of the intracranial mass. DISCUSSION The incidental finding of papilledema, with imaging to investigate the intracranial pathology revealed a large posterior fossa mass in our patient. However, the atypical features of the mass (dural based extra-axial location; extensive infiltration into adjacent structures) and the finding of blasts with Auer rods in peripheral blood helped us to diagnose CNS-MS, and avoided an extensive neurosurgical procedure and a delay in definitive therapy. Our patient had a normal CBC and the review of the peripheral blood film by an experienced Hematologist was very crucial in making a clinical diagnosis of MS. CONCLUSION Myeloid sarcomas should be considered in the differential diagnosis of an intracranial mass, particularly when accompanied by abnormal findings in the CBC.
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 | 0.004 |
| Meta-epidemiology (narrow) | 0.000 | 0.000 |
| Meta-epidemiology (broad) | 0.000 | 0.000 |
| Bibliometrics | 0.001 | 0.001 |
| Science and technology studies | 0.001 | 0.001 |
| Scholarly communication | 0.001 | 0.001 |
| Open science | 0.001 | 0.001 |
| Research integrity | 0.002 | 0.001 |
| Insufficient payload (model declined to judge) | 0.038 | 0.015 |
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".