Intrarenal epidermoid cyst mimicking a cystic renal cell carcinoma: A case report and review of literature.

Key Clinical Message: This case highlights the diagnostic pitfalls that can occur when evaluating complex cystic renal masses. Distinguishing epidermoid cysts from renal cell carcinoma is difficult but imperative to guide conservative management when appropriate, avoiding unnecessary nephrectomy. Abstract: Renal epidermoid cysts are extremely rare, with only 12 cases reported in the literature. Their radiographic features often resemble cystic renal cell carcinoma, frequently prompting unnecessary nephrectomy. A 64-year-old man with a history of nephrolithiasis presented with left flank pain and hematuria. Imaging revealed a complex cystic renal mass suspicious for renal cell carcinoma. Following left radical nephrectomy, histopathology examination revealed a benign epidermoid cyst. Renal presentation of epidermoid cyst poses unique diagnostic and therapeutic challenges. Possible pathogenesis includes ectopic epidermal implantation during embryogenesis or squamous metaplasia following chronic irritation or deficiency. Radiographic distinction from concerning entities like renal cell carcinoma is difficult but imperative to avoid extensive surgery. This case highlights the diagnostic pitfalls and management considerations for renal epidermoid cysts. Additional study of clinical and imaging factors that distinguish epidermoid cysts from renal cell carcinoma can guide conservative management when appropriate, avoiding unnecessary nephrectomy for benign disease.

Osteoma in the upper cervical spine: A case report and comprehensive literature review.

INTRODUCTION AND IMPORTANCE: Osteoma is a benign, and usually asymptomatic bone tumor normally found in the skull and facial bones, although it can occasionally occur in the long bones and spine. CASE PRESENTATION: In this article, we present a 49-year-old male patient who experienced progressive neck pain accompanied by left-sided radicular pain symptoms. Clinical investigation using various imaging techniques confirmed a bone-forming lesion located within the C1 vertebrae region. Treatment involved performing hemilaminectomy of C1 along with resection for complete removal of this extradural bone lesion, ultimately achieving symptom relief. Histopathological examination of the resected specimen leads to the diagnosis of osteoma. Along with reporting this case, we conducted a comprehensive literature review of the previously reported spinal osteoma cases. CLINICAL DISCUSSION: Histopathological examination confirmed the diagnosis of osteoma. A comprehensive literature review was conducted, revealing 16 previously reported cases of spinal osteoma. Among these, only one case involved the C1 vertebra and presented similar neurological symptoms. The review underscores the rarity of spinal osteomas and the importance of surgical intervention for symptom relief. CONCLUSION: Spinal osteomas are rare but should be considered in the differential diagnosis of patients presenting with neck pain and radicular symptoms. Surgical removal of the lesion is often necessary for symptom relief, as highlighted by our case and supported by the literature review. This case adds to the limited body of evidence on spinal osteomas and emphasizes the importance of a multidisciplinary approach for optimal patient outcomes.

Pharmacotherapeutic approach toward urological medications and vaccination during COVID-19: a narrative review.

One year after the prevalence of the novel coronavirus pandemic, some aspects of the physiopathology, treatment and progression of coronavirus 2019 disease (COVID-19) have remained unknown. Since no comprehensive study on the use of urological medications in patients with COVID-19 has been carried out, this narrative review aimed to focus on clinically important issues about the treatment of COVID-19 and urologic medications regarding efficacy, modifications, side effects and interactions in different urologic diseases. In this review, we provide information about the pharmacotherapeutic approach toward urologic medications in patients with COVID-19 infection. This study provides an overview of medications in benign prostatic hyperplasia, prostate cancer, impotence and sexual dysfunction, urolithiasis, kidney transplantation and hypertension as the most frequent diseases in which the patients are on long-term medications. Also, the effect of urologic drugs on the efficacy of vaccination is briefly discussed.

Surgical approach is associated with complication rate in sinonasal malignancy: A multicenter study.

BACKGROUND: Management of sinonasal malignancy (SNM) often includes surgical resection as part of the multimodality treatment. Treatment-related surgical morbidity can occur, yet risk factors associated with complications in this population have not been sufficiently investigated. METHODS: Adult patients with histologically confirmed SNM whose primary treatment included surgical resection were prospectively enrolled into an observational, multi-institutional cohort study from 2015 to 2020. Sociodemographic, disease, and treatment data were collected. Complications assessed included cerebrospinal fluid leak, orbital injury, intracranial injury, diplopia, meningitis, osteoradionecrosis, hospitalization for neutropenia, and subsequent chronic rhinosinusitis. The surgical approach was categorized as endoscopic resection (ER) or open/combined resection (O/CR). Associations between factors and complications were analyzed using Student's t test, Fisher's exact test, and logistic regression modeling. RESULTS: Overall, 142 patients met the inclusion criteria. Twenty-three subjects had at least 1 complication (16.2%). On unadjusted analysis, adjuvant radiation therapy was associated with developing a complication (91.3% vs 65.5%, p = 0.013). Compared with the ER group (n = 98), the O/CR group (n = 44) had a greater percentage of higher T-stage lesions (p = 0.004) and more frequently received adjuvant radiation (84.1% vs 64.4%, p = 0.017) and chemotherapy (50.0% vs 30.6%, p = 0.038). Complication rates were similar between the ER and O/CR groups without controlling for other factors. Regression analysis that retained certain factors showed O/CR was associated with increased odds of experiencing a complication (odds ratio, 3.34; 95% confidence interval, 1.06-11.19). CONCLUSIONS: Prospective, multicenter evaluation of SNM treatment outcomes is feasible. Undergoing O/CR was associated with increased odds of developing a complication after accounting for radiation therapy. Further studies are warranted to build upon these findings.

Multimodality oncologic evaluation of superficial neck and facial lymph nodes.

Involvement of lymph nodes in patients with head and neck cancers impacts treatment and prognosis. Head and neck lymph nodes are comprised of superficial and deep groups which are interconnected. The deep lymph nodes, predominantly centered along internal jugular veins, are very well-known to radiologists and clinicians. However, superficial lymph nodes that drain lymph from the scalp, face, and neck are much less recognized. Here, we describe the anatomic and imaging features of these superficial lymph nodes on CT, MRI, and PET in oncologic settings.

Association of plasma cell-free DNA with survival in patients with IDH wild-type glioblastoma.

BACKGROUND: We aimed to determine whether plasma cell-free DNA (cfDNA) concentration is associated with survival in patients with isocitrate dehydrogenase (IDH) wild-type glioblastoma (GBM). METHODS: Pre-operative and post-chemoradiotherapy blood samples were prospectively collected from patients with newly diagnosed IDH wild-type GBM. Patients underwent surgical resection or biopsy and received adjuvant radiotherapy with concomitant temozolomide. Cell-free DNA (cfDNA) was isolated from plasma and quantified using SYBR Green-based q polymerase chain reaction (qPCR). RESULTS: Sixty-two patients were enrolled and categorized into high vs. low cfDNA groups relative to the pre-operative median value (25.2 ng/mL, range 5.7-153.0 ng/mL). High pre-operative cfDNA concentration was associated with inferior PFS (median progression-free survival (PFS), 3.4 vs. 7.7 months; log-rank P = .004; hazard ratio [HR], 2.19; 95% CI, 1.26-3.81) and overall survival (OS) (median OS, 8.0 vs. 13.9 months; log-rank P = .01; HR, 2.43; 95% CI, 1.19-4.95). After adjusting for risk factors, including O6-methylguanine-DNA methyltransferase (MGMT) promoter methylation status, pre-operative cfDNA remained independently associated with PFS (HR, 2.70; 95% CI, 1.50-4.83; P = .001) and OS (HR, 2.65; 95% CI, 1.25-5.59; P = .01). Post-hoc analysis of change in cfDNA post-chemoradiotherapy compared to pre-surgery (n = 24) showed increasing cfDNA concentration was associated with worse PFS (median, 2.7 vs. 6.0 months; log-rank P = .003; HR, 4.92; 95% CI, 1.53-15.84) and OS (median, 3.9 vs. 19.4 months; log-rank P < .001; HR, 7.77; 95% CI, 2.17-27.76). CONCLUSIONS: cfDNA concentration is a promising prognostic biomarker for patients with IDH wild-type GBM. Plasma cfDNA can be obtained noninvasively and may enable more accurate estimates of survival and effective clinical trial stratification.

Anatomical Variations, Mimics, and Pitfalls in Imaging of Patients with Epilepsy.

Epilepsy is among one of the most common neurologic disorders. The role of magnetic resonance imaging (MRI) in the diagnosis and management of patients with epilepsy is well established, and most patients with epilepsy are likely to undergo at least one or more MRI examinations in the course of their disease. Recent advances in high-field MRI have enabled high resolution in vivo visualization of small and intricate anatomic structures that are of great importance in the assessment of seizure disorders. Familiarity with normal anatomic variations is essential in the accurate diagnosis and image interpretation, as these variations may be mistaken for epileptogenic foci, leading to unnecessary follow-up imaging, or worse, unnecessary treatment. After a brief overview of normal imaging anatomy of the mesial temporal lobe, this article will review a few important common and uncommon anatomic variations, mimics, and pitfalls that may be encountered in the imaging evaluation of patients with epilepsy.

Epilepsy Lesion Localization is not Predicted by Developmental Venous Anomaly Location or its FDG-PET Metabolic Activity.

BACKGROUND AND PURPOSE: This study's purpose is to correlate location and metabolic activity of developmental venous anomalies (DVAs) in epilepsy patients to the seizure focus as determined by ictal/interictal encephaloelectrogram (EEG). METHODS: A retrospective search was performed for epilepsy patients with DVAs who underwent brain 18 F-fluorodeoxyglucose positron emission tomography (18 F-FDG-PET) and magnetic resonance imaging (MRI). MRI exams were analyzed to characterize DVA location and associated structural findings. MRI and PET images were co-registered and assessment of 18 F-FDG uptake in the DVA territory was performed. The electronic medical record was reviewed for each subject to determine seizure semiology and site of seizure focus by ictal/interictal EEG. RESULTS: Twenty-eight DVAs in 25 patients were included. Twelve DVAs demonstrated regional metabolic abnormality on 18 F-FDG-PET. There was no significant correlation between DVA site and seizure focus on EEG. DVA location was concordant with EEG seizure focus in three subjects, and all three demonstrated hypometabolism on 18 F-FDG-PET. This significance remains indeterminate, as one of these DVAs was associated with cavernoma, which could serve as the true seizure focus, and one of the patients underwent resection of the DVA without decrease in seizure frequency. Furthermore, there was no statistically significant relationship between DVA metabolic activity and DVA-EEG lobar or laterality concordance. CONCLUSIONS: In this sample, there is no significant correlation between location of DVA and seizure focus, and hypometabolism within the DVA territory is not predictive of EEG/DVA co-localization. As use of 18 F-FDG-PET for evaluation of epilepsy increases, knowledge of this poor correlation is important to avoid diagnostic confusion and potentially unnecessary surgery in epilepsy patients.

Emerging Techniques in Imaging of Glioma Microenvironment.

Magnetic resonance imaging (MRI) has been the cornerstone of imaging of brain tumors in the past 4 decades. Conventional MRI remains the workhorse for neuro-oncologic imaging, not only for basic information such as location, extent, and navigation but also able to provide information regarding proliferation and infiltration, angiogenesis, hemorrhage, and more. More sophisticated MRI sequences have extended the ability to assess and quantify these features; for example, permeability and perfusion acquisitions can assess blood-brain barrier disruption and angiogenesis, diffusion techniques can assess cellularity and infiltration, and spectroscopy can address metabolism. Techniques such as fMRI and diffusion fiber tracking can be helpful in diagnostic planning for resection and radiation therapy, and more sophisticated iterations of these techniques can extend our understanding of neurocognitive effects of these tumors and associated treatment responses and effects. More recently, MRI has been used to go beyond such morphological, physiological, and functional characteristics to assess the tumor microenvironment. The current review highlights multiple recent and emerging approaches in MRI to characterize the tumor microenvironment.

Imaging and histopathologic correlates of plasma cell-free DNA concentration and circulating tumor DNA in adult patients with newly diagnosed glioblastoma.

BACKGROUND: Plasma cell-free DNA (cfDNA) concentration is lower in glioblastoma (GBM) compared to other solid tumors, which can lead to low circulating tumor DNA (ctDNA) detection. In this study, we investigated the relationship between multimodality magnetic resonance imaging (MRI) and histopathologic features with plasma cfDNA concentration and ctDNA detection in patients with treatment-naive GBM. METHODS: We analyzed plasma cfDNA concentration, MRI scans, and tumor histopathology from 42 adult patients with newly diagnosed GBM. Linear regression analysis was used to examine the relationship of plasma cfDNA concentration before surgery to imaging and histopathologic characteristics. In a subset of patients, imaging and histopathologic metrics were also compared between patients with and without a detected tumor somatic mutation. RESULTS: Tumor volume with elevated (>1.5 times contralateral white matter) rate transfer constant (K ep, a surrogate of blood-brain barrier [BBB] permeability) was independently associated with plasma cfDNA concentration (P = .001). Histopathologic characteristics independently associated with plasma cfDNA concentration included CD68+ macrophage density (P = .01) and size of tumor vessels (P = .01). Patients with higher (grade ≥3) perivascular CD68+ macrophage density had lower volume transfer constant (K trans, P = .01) compared to those with lower perivascular CD68+ macrophage density. Detection of at least 1 somatic mutation in plasma cfDNA was associated with significantly lower perivascular CD68+ macrophages (P = .01). CONCLUSIONS: Metrics of BBB disruption and quantity and distribution of tumor-associated macrophages are associated with plasma cfDNA concentration and ctDNA detection in GBM patients. These findings represent an important step in understanding the factors that determine plasma cfDNA concentration and ctDNA detection.

Variations of the CNS Venous System Mimicking Pathology: Spectrum of Imaging Findings.

Variations in the venous drainage of the central nervous system can have imaging and clinical findings that mimic pathology, presenting a challenge for neuroimagers and clinicians. Patients with these variants may undergo unnecessary testing, and patients with pathology may receive delayed diagnoses because of overlap with benign findings. Consequently, the accurate identification of venous variations on cross-sectional imaging and angiography and their potential causes are critical for differentiating benign imaging variants from potential pathologic processes requiring further evaluation. For example, in the epidural space, benign dilation of the epidural venous plexus may be mistaken for evidence of a fistula, abscess, or metastasis. Hypoplasia of a dural venous sinus or an arachnoid granulation may mimic venous sinus thrombosis. The superior ophthalmic vein may demonstrate benign dilation in intubated patients, mimicking thrombosis, increased intracranial pressure, orbital varix, inflammatory pseudotumor, or other conditions. Furthermore, certain venous variations, such as the occipital sinus or emissary veins, may complicate surgery or herald pathology and should be reported. In addition, some supposedly benign variations, such as the developmental venous anomaly, can be complicated by pathology. The objective of this review article is to provide a descriptive and pictorial review of common anatomic and physiologic variations in the venous drainage system of the brain, spine, and orbits that can mimic pathology. Neuroimaging findings of related pathologies and differences in clinical presentations will also be discussed to assist in the approach to differential diagnosis.

Reduced Intercarotid Artery Distance in Syndromic and Isolated Brachycephaly.

INTRODUCTION: The morphology of the skull base can be altered in craniosynostoses. The objective of this study is to evaluate the reduced intercarotid artery distance in the lacerum segment in patients with syndromic and isolated brachycephaly. MATERIALS AND METHODS: The distances between the inner walls of the carotid canal at the lacerum segment were measured on high-resolution CT scans in children with Crouzon (25), Pfeiffer (21), Apert (26), Saethre-Chotzen (7) syndromes, isolated bicoronal synostosis (9), and compared to an age-matched control group (30). RESULTS: A significantly smaller mean distance between carotid canal walls was observed in Crouzon (11.1 ± 4.9 mm), Pfeiffer (9.6 ± 5.1 mm), Apert (12.3 ± 4.3 mm), Saethre-Chotzen (14.8 ± 3.0 mm) syndromes, and isolated bicoronal synostosis (14.9 ± 3.7 mm) as compared to the control group (19.7 ± 2.4 mm, P < 0.001, P < 0.001, P < 0.001, P = 0.005, and P = 0.002, respectively). There was no statistically significant difference in intercarotid canal distance among the Apert, Saethre-Chotzen and isolated bicoronal synostosis groups. Overall, the brachycephalic group showed reduced intercarotid canal distance comparing to controls (P < 0.001). DISCUSSION AND CONCLUSIONS: There is significant reduction of the distance between carotid canals in brachycephalic patients. This distance is more significantly altered in FGFR-related brachycephaly syndromes (especially Crouzon and Pfeiffer syndromes), than Saethre-Chotzen syndrome (TWIST1 mutation) and isolated non-syndromic bicoronal synostosis. This study highlights the importance of FGFRs in shaping the skull base. Altered vascular course of the internal carotid arteries can have important implications in planning skull base surgery in brachycephalic patients.

Chapter 6 Non-Squamous Cell Causes of Cervical Lymphadenopathy.

Cervical lymphadenopathy is a common indication for imaging evaluation of the neck. Besides metastatic squamous cell carcinoma of the head and neck, cervical lymphadenopathy can be due to many causes, with simple reactive lymphadenopathy on one end of the spectrum and malignant lymphadenopathy due to a distant infraclavicular primary, on the other end. A systematic approach to the cause of cervical lymphadenopathy, which includes pattern of lymph node enlargement, lymph node characteristics, systemic symptoms, and extranodal abnormalities, can be very useful in arriving at the correct diagnosis. In this article, various patterns of cervical lymphadenopathy due to non-squamous cell causes are discussed.

Chapter 8 On the Horizon: Advanced Imaging Techniques to Improve Noninvasive Assessment of Cervical Lymph Nodes.

Conventional imaging modalities are limited in the evaluation of lymph nodes as they predominantly rely on size and morphology, which have suboptimal sensitivity and specificity for malignancy. In this review we will explore the role of "on the horizon" advanced imaging modalities that can look beyond the size and morphologic features of a cervical lymph node and explore its molecular nature and can aid in personalizing therapy rather than use the "one-size-fits-all" approach.

Neuroimaging in Central Nervous System Lymphoma.

Primary central nervous system lymphoma (PCNSL) is a rare aggressive high-grade type of extranodal lymphoma. PCNSL can have a variable imaging appearance and can mimic other brain disorders such as encephalitis, demyelination, and stroke. In addition to PCNSL, the CNS can be secondarily involved by systemic lymphoma. Computed tomography and conventional MRI are the initial imaging modalities to evaluate these lesions. Recently, however, advanced MRI techniques are more often used in an effort to narrow the differential diagnosis and potentially inform diagnostic and therapeutic decisions.

Neuroimaging in Leukemia.

Leukemias are a heterogeneous group of hematologic malignancies that results from uncontrolled neoplastic proliferation of undifferentiated or partially differentiated hematopoietic cells. Patients with acute leukemia can have a variety of craniocerebral complications, which can result from direct leukemic involvement, secondary to cerebrovascular or infectious complications of leukemia, or can be treatment related. Imaging plays a central role in evaluating the central nervous system during treatment in patients with leukemia. CT scan is usually considered an effective initial imaging modality to evaluate for cerebrovascular complications. MRI is considered the imaging modality of choice due to its versatility.

Temporal patterns of 18 F-fluorodeoxyglucose positron emission tomography/computed tomography sinonasal uptake after treatment of sinonasal malignancy.

BACKGROUND: Current guidelines have identified 10 to 12 weeks posttreatment as the ideal time-point for improved diagnostic accuracy of positron emission tomography/computed tomography (PET/CT) for deep tissue sites of the head and neck. After treatment, the sinonasal skull base is predisposed to prolonged inflammation that may render this time-point inappropriate for initial posttreatment imaging surveillance for sinonasal malignancies. The purpose of this study is to evaluate temporal trends in 18 F-fluorodeoxyglucose (18 FDG) sinonasal uptake after treatment for sinonasal malignancies to better elucidate the optimal time-point for initial PET/CT posttreatment evaluation in this patient population. METHODS: A retrospective analysis of all successfully treated and non-locally recurrent sinonasal malignancies over a 15-year study period (2000 to 2015) was performed at our institution. Posttreatment 18 FDG PET/CT standardized uptake value data were collected and compared between various time-points (2 to 4 months, 5 to 12 months, 5 to 24 months, and 13 to 24 months) using an independent-samples t test. RESULTS: A statistically significant difference was noted between the posttreatment time windows 2 to 4 and 5 to 12 months (p = 0.048) as well as 2 to 4 and 5 to 24 months (p = 0.02). A trend toward significance was seen when comparing 2 to 4 and 13 to 24 months (p = 0.083). CONCLUSION: Our analysis of PET/CT in patients previously treated for sinonasal malignancy suggests that the posttreatment sinonasal skull base is characterized by a prolonged period of hypermetabolism that endures beyond the period previously described for deep tissue sites of the head and neck. These findings prompt a reevaluation of the previously described 10- to 12-week cutoff point for initial posttreatment PET/CT for head and neck squamous cell carcinoma as applied to sinonasal malignancies.

Utility of fat-suppressed sequences in differentiation of aggressive vs typical asymptomatic haemangioma of the spine.

OBJECTIVE: While haemangiomas are common benign vascular lesions involving the spine, some behave in an aggressive fashion. We investigated the utility of fat-suppressed sequences to differentiate between benign and aggressive vertebral haemangiomas. METHODS: Patients with the diagnosis of aggressive vertebral haemangioma and available short tau inversion-recovery or T2 fat saturation sequence were included in the study. 11 patients with typical asymptomatic vertebral body haemangiomas were selected as the control group. Region of interest signal intensity (SI) analysis of the entire haemangioma as well as the portion of each haemangioma with highest signal on fat-saturation sequences was performed and normalized to a reference normal vertebral body. RESULTS: A total of 8 patients with aggressive vertebral haemangioma and 11 patients with asymptomatic typical vertebral haemangioma were included. There was a significant difference between total normalized mean SI ratio (3.14 vs 1.48, p = 0.0002), total normalized maximum SI ratio (5.72 vs 2.55, p = 0.0003), brightest normalized mean SI ratio (4.28 vs 1.72, p < 0.0001) and brightest normalized maximum SI ratio (5.25 vs 2.45, p = 0.0003). Multiple measures were able to discriminate between groups with high sensitivity (>88%) and specificity (>82%). CONCLUSION: In addition to the conventional imaging features such as vertebral expansion and presence of extravertebral component, quantitative evaluation of fat-suppression sequences is also another imaging feature that can differentiate aggressive haemangioma and typical asymptomatic haemangioma. ADVANCES IN KNOWLEDGE: The use of quantitative fat-suppressed MRI in vertebral haemangiomas is demonstrated. Quantitative fat-suppressed MRI can have a role in confirming the diagnosis of aggressive haemangiomas. In addition, this application can be further investigated in future studies to predict aggressiveness of vertebral haemangiomas in early stages.