Myeloid sarcoma with megakaryoblastic differentiation mimicking a sellar tumor

Myeloid sarcoma (MS) is a localized extra‐medullary tumor mass of immature myeloid cells, arising de novo or related to acute myeloid leukemia, of which it can be a forerunner, a coinciding or late event. Less commonly, MS represents an acute blastic transformation of myelodysplastic syndromes or myeloproliferative neoplasms. This rare condition commonly consists of a proliferation of more or less immature cells with a myeloid immunophenotype, very exceptional cases showing a megakaryoblastic or erythroid differentiation. The most common localization of MS is the skin, lymph node, soft tissues and bones, but CNS involvement is exceedingly rare, with no cases reported in the sellar region. We report a 54‐year‐old man, affected by myeloproliferative neoplasm, JAK2 V617F‐positive of 13 years duration, who acutely presented with a third cranial nerve palsy; neuroradiology documented a space‐occupying lesion at the level of the sellar, upper clival and right parasellar regions, that was sub‐totally removed with a trans‐sphenoidal approach. The histological examination documented a proliferation of large, blastic cells, frequently multinucleated; a diagnosis of MS with megakaryoblastic differentiation, arising in a background of chronic idiopathic myelofibrosis, was suggested by immunohistochemistry, owing to CD42b, CD45, CD61 and LAT (linker for activation of T cells) positivity. In addition, homozygous JAK2 V617F mutation was detected from the myeloid sarcoma specimen. A few weeks after surgery, an acute blastic leukemic transformation occurred and, despite chemotherapy, the patient died 2 months after surgery. To the best of our knowledge, this is the first MS case with megakaryoblastic differentiation arising within the CNS.     

Mapping the Gastrointestinal Quality of Life Index to Short-Form 6D utility scores

Purpose

The Gastrointestinal Quality of Life Index (GIQLI) is a disease-specific quality of life instrument that is commonly used in gastrointestinal disorders. However, no preference weights, which are used to calculate quality-adjusted life years for cost-effectiveness analyses, for this instrument have been assigned. Therefore, the objective of this study was to develop a mapping function to derive utility scores for the GIQLI.

Methods

Patients undergoing elective laparoscopic cholecystectomy completed the short-form 6D (SF-6D), a preference-weighted utility measure, and the GIQLI at baseline and at 1 wk and 1 mo postoperatively. The responsiveness of the SF-6D to expected postoperative changes as well as the correlation between the SF-6D and the GIQLI was investigated. Ordinary least squares regression was performed to derive a mapping function using the baseline values, which was then validated using postoperative values. Adjusted r², mean absolute error, and root mean square error was used to determine model performance.

Results

A total of 50 patients were included in the study (mean age 51.1 [standard deviation 16.8], 28% male). The SF-6D and GIQLI domains were responsive to expected postoperative changes, and there was high correlation between the SF-6D and four of the five GIQLI domains (excluding treatment effects). The final mapping function explained 63% of the variance in the derivation sample but had relatively high mean absolute error (0.075 and 0.067 in the 1-wk and 1-mo samples, respectively) and adjusted root mean square error (13.1% and 12.0% in the 1-wk and 1-mo samples, respectively).

Conclusions

The GIQLI can be accurately mapped to SF-6D preference weights at the group level but may be too inexact at the individual level.     

Primary multicentric anaplastic pleomorphic xanthoastrocytoma with atypical features

Pleomorphic xanthoastrocytoma (PXA) is a rare tumor with good prognosis after surgery. Few cases of anaplastic PXA (either de novo or secondary to transformation of a recurrent low grade PXA) have been reported. Moreover, primary anaplastic PXA with dissemination at diagnosis has been described only in two patients, to our knowledge. We report the first case of primary multicentric anaplastic PXA and discuss its atypical features and the pertinent literature.     

Electronystagmography versus videonystagmography in diagnosis of vertigo

Objectives  

Vertigo is a very common symptom mainly caused by the lesion of vestibular system (peripheral or central) and often accompanied by some work-related diseases and occupational intoxications. The aim of this study was to assess the value of electronystagmography (ENG) and videonystagmography (VNG) for diagnosing vertigo of various origin.