Posterior fossa Hodgkin's lymphoma radiographically mimicking an arteriovenous malformation: illustrative case.

BACKGROUND: Intracranial Hodgkin's lymphoma (HL) is an exceedingly rare condition that is at an increased risk of misdiagnosis and mismanagement, especially when initial radiographic evidence points to an alternative pathology. OBSERVATIONS: The authors describe the case of a 75-year-old female who presented with a posterior fossa lesion initially concerning for a vascular malformation on computed tomography imaging due to perilesional hypervascularity. Subsequent angiography revealed a developmental venous anomaly (DVA) but no arteriovenous shunting. The patient's clinical history combined with magnetic resonance imaging findings prompted a tissue biopsy, which demonstrated a rare case of central nervous system (CNS) HL. The neoangiogenesis of this CNS HL with an adjacent DVA contributed to the original radiographic misdiagnosis of an arteriovenous malformation. HL's angiogenic potential, coupled with the proangiogenic environment induced around DVAs, may have contributed to this rare CNS HL metastasis to the cerebellum. The potential misdiagnosis of posterior fossa CNS HL has also been seen in several prior cases reviewed herein. LESSONS: Hypervascular tumors, especially when associated with an adjacent DVA, should also be considered when first evaluating suspected intracranial vascular lesions. Although rare, CNS HL should be included in the differential diagnosis for patients with a prior history of HL. https://thejns.org/doi/10.3171/CASE24238.

Papillary craniopharyngioma in a patient following resection of nonfunctioning pituitary adenoma: illustrative case.

BACKGROUND: Although craniopharyngioma and pituitary adenoma are common tumors of the sellar or suprasellar region, the development of papillary craniopharyngioma in the same sellar region after resection of a nonfunctioning pituitary adenoma has not been reported. OBSERVATIONS: Here the authors report the first case of craniopharyngioma that developed long after resection of a pituitary adenoma. A 66-year-old male patient underwent endoscopic transsphenoidal resection for a large sellar mass, which histopathologically confirmed the diagnosis of a pituitary adenoma. He had an excellent recovery after surgery. For several years, he had no clinical or imaging evidence of tumor recurrence and then was lost to follow-up. Seven years after the initial surgery, the patient returned with a one-month history of visual field defects, and imaging confirmed a heterogeneous, cystic suprasellar mass. Endoscopic transsphenoidal resection of the tumor was performed, and histological examination showed it to be a papillary craniopharyngioma. LESSONS: Neurosurgeons should be aware that after pituitary adenoma resection, a recurrent mass could be a craniopharyngioma, with implications for very different management recommendations.

Metastatic Subdural Hematoma with Dural Metastasis Secondary to Poorly Differentiated Adenocarcinoma of Unknown Origin.

BACKGROUND: Metastatic subdural hematoma with dural metastasis in the setting of an underlying malignancy is a rare condition that is difficult to diagnose and associated with a poor prognosis. Knowledge of this rare entity is of a paramount importance to neurosurgeons, as its diagnosis may affect the management plan and overall survival. Here, we report a rare case of atraumatic subdural hematoma with dural metastasis in a patient with poorly differentiated adenocarcinoma of unknown origin. CASE DESCRIPTION: A 34-year-old man presented with an insidious onset of headaches, severe light headedness, progressive low back pain, and generalized weakness for 2 weeks. On imaging, he was found to have left-sided acute on chronic subdural hematoma with midline shift. The patient underwent surgical evacuation of the hematoma and the subdural membrane was biopsied. Histopathologic examination revealed metastatic poorly differentiated adenocarcinoma of unclear origin. A full metastatic workup was unremarkable. CONCLUSIONS: Metastatic subdural hematoma with dural metastasis should be included in differential diagnosis of subdural hematoma, especially in patients with atypical presentation and in the presence of an underlying malignancy, as it may affect the management plan and overall survival.

Fractal Analysis May Improve the Preoperative Identification of Atypical Meningiomas.

Background: There is no objective and readily accessible method for the preoperative determination of atypical characteristics of a meningioma grade. Objective: To evaluate the feasibility of using fractal analysis as an adjunctive tool to conventional radiological techniques in visualizing histopathological features of meningiomas. Methods: A group of 27 patients diagnosed with atypical (WHO grade II) meningioma and a second group of 27 patients with benign (WHO grade I) meningioma were enrolled in the study. Preoperative brain magnetic resonance (MR) studies (T1-wieghted, post-gadolinium) were processed and analyzed to determine the average fractal dimension (FDa) and maximum fractal dimension (FDm) of the contrast-enhancing region of the tumor using box-count method. FDa and FDm as well as particular radiological features were included in the logistic regression model as possible predictors of malignancy. Results: The cohort consisted of 34 women and 20 men, mean age of 62 ± 15 yr. Fractal analysis showed good interobserver reproducibility (Kappa >0.70). Both FDa and FDm were significantly higher in the atypical compared to the benign meningioma group (P < .0001). Multivariate logistic regression model reached statistical significance with P = .0001 and AUC = 0.87. The FDm, which was greater than 1.31 (odds ratio [OR], 12.30; P = .039), and nonskull base localization (OR, .052; P = .015) were confirmed to be statistically significant predictors of the atypical phenotype. Conclusion: Fractal analysis of preoperative MR images appears to be a feasible adjunctive diagnostic tool in identifying meningiomas with potentially aggressive clinical behavior.

Characterization of Prohibitins in Male Reproductive System and their Expression under Oxidative Stress.

PURPOSE: We investigated the expression and location of prohibitin 1 and 2 of the prohibitin family in the male reproductive system and their potential roles during the oxidative stress response in a rat model. MATERIALS AND METHODS: Semiquantitative polymerase chain reaction, Western blot, immunohistochemistry and indirect immunofluorescence were performed to examine the expression and localization of prohibitins. Oxidative damage was evaluated using a commercially available malondialdehyde kit. Histological damage induced by doxorubicin injection was examined by hematoxylin and eosin staining. RESULTS: Prohibitin 1 and 2 were ubiquitously expressed in various human tissues with distinct high expression in the epididymis. In the human testis and epididymis they were localized in the cytoplasm of diverse cell types. Prohibitin 1 was located on the entire tail region of human ejaculated spermatozoa while prohibitin 2 was specifically localized on the equatorial region. In spermatozoa from young men with asthenozoospermia the percent of spermatozoa with positive staining as well as the fluorescence intensity of prohibitin 2 was much lower than in the spermatozoa of healthy donors. Uniform expression of prohibitins in the testis and epididymis of the rat during postnatal development suggested conserved and vital biological functions. Moreover under oxidative stress induced by doxorubicin injection the expression of prohibitin 1 and 2 was significantly down-regulated in the rat testis with significant histomorphological changes. CONCLUSIONS: To our knowledge this research represents the first systematic study of prohibitins in the male reproductive system. It lays the foundation for further functional studies and provides potential therapeutic targets for infertility induced by oxidative stress.