RF05 | PSUN365 Insulinoma: A Case Report of a Rare Functioning Neuroendocrine Tumor

 

Insulinoma is a rare functional neuroendocrine tumor that causes inappropriate release of insulin, resulting in symptoms of hypoglycemia which would resolve promptly following glucose administraton. Its incidence is 1 to 3 per 1,000,000 population per year.

Case presentation

This study reports on a 64 year old female with no known co-morbidities who was seen in the endocrinology clinic due to episodes of blurring of vision, lightheadedness and shakiness. Glucose levels as low as 40mg/dL were detected with glucometer during these episodes. Symptom would improve after eating carbohydrate rich food. Symptom onset was 4 years prior to consult. Patient also reported weight gain as she would over-eat to treat her symptoms. The patient came in for evaluation and management of Hypoglycemia. Blood tests revealed high insulin (146.60 uU/mL; reference range: 5.00–10.00 uU/mL) and C-peptide level (7.45 ng/mL; reference range: 0.78–5.19 ng/mL) despite low plasma glucose level (36 mg/dL). Dynamic CT scan of the pancreas revealed an arterially enhancing nodule with intralesional calcification in the distal pancreatic body for which an insulinoma is considered. She underwent distal pancreatectomy and her symptoms showed complete resolution. Surgical pathology was consistent with well differentiated Neuroendocrine tumor.

Conclusion

Clinicians should have a high index of suspicion for Insulinoma in patients with history of recurrent episodes of blurring of vision, lightheadedness and shakiness, particularly if these symptoms would resolve after food intake. Such condition entails proper and timely diagnosis, localization of the tumor and treatment and involves several specialties.

Presentation: Saturday, June 11, 2022 1:36 p.m. - 1:41 p.m., Sunday, June 12, 2022 12:30 p.m. - 2:30 p.m.

The Effect of Virtual Mindfulness-Based Interventions on Sleep Quality: A Systematic Review of Randomized Controlled Trials

PURPOSE OF REVIEW

We summarized peer-reviewed literature investigating the effect of virtual mindfulness-based interventions (MBIs) on sleep quality. We aimed to examine the following three questions: (1) do virtual MBIs improve sleep quality when compared with control groups; (2) does the effect persist long-term; and (3) is the virtual delivery method equally feasible compared to the in-person delivery method?

RECENT FINDINGS

Findings suggest that virtual MBIs are equivalent to evidence-based treatments, and to a limited extent, more effective than non-specific active controls at reducing some aspects of sleep disturbance. Overall, virtual MBIs are more effective at improving sleep quality than usual care controls and waitlist controls. Studies provide preliminary evidence that virtual MBIs have a long-term effect on sleep quality. Moreover, while virtual MBI attrition rates are comparable to in-person MBI attrition rates, intervention adherence may be compromised in the virtual delivery method. This review highlights virtual MBIs as a potentially effective alternative to managing sleep disturbance during pandemic-related quarantine and stay-at-home periods. This is especially relevant due to barriers of accessing in-person interventions during the pandemic. Future studies are needed to explore factors that influence adherence and access to virtual MBIs, with a particular focus on diverse populations.

The effect of mindfulness meditation on sleep quality: a systematic review and meta-analysis of randomized controlled trials

There is a growing interest in the effectiveness of mindfulness meditation for sleep disturbed populations. Our study sought to evaluate the effect of mindfulness meditation interventions on sleep quality. To assess for relative efficacy, comparator groups were restricted to specific active controls (such as evidenced-based sleep treatments) and nonspecific active controls (such as time/attention-matched interventions to control for placebo effects), which were analyzed separately. From 3303 total records, 18 trials with 1654 participants were included. We determined the strength of evidence using four domains (risk of bias, directness of outcome measures, consistency of results, and precision of results). At posttreatment and follow-up, there was low strength of evidence that mindfulness meditation interventions had no effect on sleep quality compared with specific active controls (ES 0.03 (95% CI -0.43 to 0.49)) and (ES -0.14 (95% CI -0.62 to 0.34)), respectively. Additionally, there was moderate strength of evidence that mindfulness meditation interventions significantly improved sleep quality compared with nonspecific active controls at postintervention (ES 0.33 (95% CI 0.17-0.48)) and at follow-up (ES 0.54 (95% CI 0.24-0.84)). These preliminary findings suggest that mindfulness meditation may be effective in treating some aspects of sleep disturbance. Further research is warranted.

Population pharmacokinetics-pharmacodynamics of vedolizumab in patients with ulcerative colitis and Crohn's disease

BACKGROUND

Vedolizumab, an anti-α(4)β(7) integrin monoclonal antibody (mAb), is indicated for treating patients with moderately to severely active ulcerative colitis (UC) and Crohn's disease (CD). As higher therapeutic mAb concentrations have been associated with greater efficacy in inflammatory bowel disease, understanding determinants of vedolizumab clearance may help to optimise dosing.

AIMS

To characterise vedolizumab pharmacokinetics in patients with UC and CD, to identify clinically relevant determinants of vedolizumab clearance, and to describe the pharmacokinetic-pharmacodynamic relationship using population modelling.

METHODS

Data from a phase 1 healthy volunteer study, a phase 2 UC study, and 3 phase 3 UC/CD studies were included. Population pharmacokinetic analysis for repeated measures was conducted using nonlinear mixed effects modelling. Results from the base model, developed using extensive phase 1 and 2 data, were used to develop the full covariate model, which was fit to sparse phase 3 data.

RESULTS

Vedolizumab pharmacokinetics was described by a 2-compartment model with parallel linear and nonlinear elimination. Using reference covariate values, linear elimination half-life of vedolizumab was 25.5 days; linear clearance (CL(L)) was 0.159 L/day for UC and 0.155 L/day for CD; central compartment volume of distribution (V(c)) was 3.19 L; and peripheral compartment volume of distribution was 1.66 L. Interindividual variabilities (%CV) were 35% for CLL and 19% for V(c); residual variance was 24%. Only extreme albumin and body weight values were identified as potential clinically important predictors of CL(L).

CONCLUSIONS

Population pharmacokinetic parameters were similar in patients with moderately to severely active UC and CD. This analysis supports use of vedolizumab fixed dosing in these patients. Clinicaltrials.gov Identifiers: NCT01177228; NCT00783718 (GEMINI 1); NCT00783692 (GEMINI 2); NCT01224171 (GEMINI 3).

Diffusion-weighted imaging in acute hyperammonemic encephalopathy

Magnetic resonance imaging (MRI) findings associated with chronic liver disease are characterized by cerebral atrophy and bilateral, symmetric hyperintensities of the globus pallidus on T1-weighted images without corresponding signal intensities in T2-weighted images. Recently, distinct MRI changes of acute hepatic encephalopathy have been described which may be misinterpreted given their resemblance to hypoxic-ischemic injury imaging changes as well as their limited description in the neurologic literature. We describe 3 cases of acute hyperammonemic encephalopathy primarily characterized by restricted diffusion involving the insular and cingulate cortices and thalamus bilaterally.

The coming-out process and its adaptational and health-related associations among gay, lesbian, and bisexual youths: stipulation and exploration of a model

A model is proposed and explored that links the coming-out process to the psychological functioning (i.e., self-esteem and distress) and sexual behaviors of gay, lesbian, and bisexual youths recruited from gay-focused community-based and college organizations in New York City. The coming-out process is multidimensional, consisting, as defined here, of involvement in gay/lesbian activities, attitudes toward homosexuality, comfort with homosexuality, self-disclosure of sexual identity to others, and sexual identity. The coming-out dimensions were related to self-esteem, distress, and unprotected sexual behaviors. In addition, the relations between the coming-out dimensions and unprotected sexual behaviors were explained by psychological functioning. In particular, limited involvement in gay/lesbian activities was associated with more unprotected sex. Negative attitudes toward homosexuality were related directly to more unprotected sex, and they were related indirectly to more unprotected sex by means of increasing emotional distress. These and other findings have implications for designing preventive interventions to increase the youths' psychological functioning and reduce their unprotected sexual behaviors.

Sexual risk behaviors of Gay, Lesbian, and bisexual youths in New York City: prevalence and correlates

The lifetime and recent sexual risk behaviors of 156 Gay, Lesbian, and bisexual youths, recruited from Gay-focused organizations in New York City, were examined. The data indicated seven reasons why the youths are at risk for HIV and other STDs: They initiated sex during early adolescence; their first sexual partners were older than they were; HIV barrier methods (e.g., condoms) were initiated subsequent to sexual debut; many lifetime sexual partners and encounters were reported; some youths exchanged sex for goods; many youths reported having had at least one partner at risk for HIV; and the youths engaged in unprotected sexual behaviors during the past 3 months. Significant gender differences emerged (e.g., the male youths reported more lifetime same-sex partners than the female youths; the female youths reported more lifetime other-sex partners than the male youths). Recent sexual risk behaviors (i.e., numbers of same-sex partners, encounters, and unprotected sex during the past 3 months) were related significantly to the youths' average degree of emotional involvement in or average duration of intimate relationships.

Understanding the unprotected sexual behaviors of gay, lesbian, and bisexual youths: an empirical test of the cognitive-environmental model

The cognitive-environmental model (CEM; M. Fishbein et al., 1991) was used to understand the unprotected sexual behaviors of 156 gay, lesbian, and bisexual youths. Unprotected anal sex among the males was associated directly with poor protection skills (e.g., incorrect use of barrier methods, such as condoms), poor intentions to use barrier methods, and poor norms by sexual partners concerning barrier methods. Furthermore, the association between low self-efficacy and increasing unprotected anal sex was attributed to poor intentions. Direct associations of unprotected oral sex with poor intentions and poor partner norms also emerged, as did an indirect relation between unprotected oral sex and low self-efficacy via poor intentions. These last 3 findings were replicated when examining unprotected oral or vaginal-digital sex among the females. Relations among the CEM factors supported some CEM-theoretical propositions.

Understanding the unprotected sexual behaviors of gay, lesbian, and bisexual youths: an empirical test of the cognitive-environmental model

The cognitive-environmental model (CEM; M. Fishbein et al., 1991) was used to understand the unprotected sexual behaviors of 156 gay, lesbian, and bisexual youths. Unprotected anal sex among the males was associated directly with poor protection skills (e.g., incorrect use of barrier methods, such as condoms), poor intentions to use barrier methods, and poor norms by sexual partners concerning barrier methods. Furthermore, the association between low self-efficacy and increasing unprotected anal sex was attributed to poor intentions. Direct associations of unprotected oral sex with poor intentions and poor partner norms also emerged, as did an indirect relation between unprotected oral sex and low self-efficacy via poor intentions. These last 3 findings were replicated when examining unprotected oral or vaginal-digital sex among the females. Relations among the CEM factors supported some CEM-theoretical propositions.

Phenol toxicity in leukemia cells: a radical process?

The multiple functions of the phenol moiety that are widely present in disparate sources such as drugs, pesticides, teas, fuel additives and surfactants have not been clearly delineated. The differences in behavior of phenols, which run the gamut from aberrations in DNA/chromosomes to suppression of genotoxic activity of carcinogenic compounds, merit further attention. In this study, a through examination of the growth inhibition patterns of 37, simple 3- and 4-substituted phenols in mouse leukemia cells was carried out and the following quantitative structure-activity relationship (QSAR) was obtained for the 23 electron releasing substituents in X-phenols: log 1/IC50 = -1.58 sigma(+) +0.21 log P + 3.10. In this QSAR, IC50 is the concentration of phenol that induces 50% inhibition of growth. P is a measure of the hydrophobicity of each phenol and Brown's electronic parameter, sigma+, represents the electronic effect of the substituent. The negative dependence on sigma+ is strongly reminiscent of what is observed in the developmental toxicity of phenols on rat embryos as well as for the radical abstraction of a hydrogen atom from phenolic groups. The other 15 electron-attracting substituted X-phenols clearly show a linear dependence on hydrophobicity alone: Log 1/IC50 = 0.62 log P + 2.35. The bifurcation in mechanism of action of this large set of diverse phenols is novel and unusual. It suggests that two distinct processes are operative. In the case of electron releasing substituted phenols, the observations are not inconsistent with a radical mediated process while with electron attracting substituted phenols, non-specific toxicity as modulated by hydrophobicity, appears to predominate.

Effects of enalapril in rats with pressure overload cardiac hypertrophy

1. The effects of the ACE inhibitor enalapril were studied in rats with cardiac hypertrophy induced by abdominal aortic constriction. This experimental model has shown that pump failure can be evidenced only during increased workload. 2. Under basal conditions, enalapril at 1-3 mg/kg induced a significant reduction in blood pressure. During the acute volume loading or the increase in afterload due to a total aortic occlusion, only rats treated with 3 mg/kg enalapril, but not 1 mg/kg, received a hemodynamic benefit that was paralleled by a significant reduction in cardiac hypertrophy. 3. The present study demonstrates that reduction in blood pressure on its own was not sufficient to improve cardiac function. A decrease in blood pressure accompanied with hypetrophy regression were necessary to normalize hemodynamic parameters in pressure-overloaded rats.

Mixed arteriovenous malformation and capillary telangiectasia: a rare subset of mixed vascular malformations. Case report

In this report, the authors discuss the case of a patient with a mixed cerebrovascular malformation in which an arteriovenous malformation (AVM) was associated with a capillary telangiectasia. Recent reports have contained reviews of various subsets of mixed malformations. To the authors' knowledge, however, this is the first report of a mixed vascular malformation with both arterial and capillary components. The patient underwent complete resection of the AVM after presenting with a clinical hemorrhage. She required a second operation to resect the capillary telangiectasia after new symptoms developed several months following the first procedure. The authors conclude that a mixed AVM-capillary telangiectasia is a rare but distinct entity.

Differential regulation of AP-1 and novel TRE-specific DNA-binding complexes during differentiation of oligodendrocyte-type-2-astrocyte (O-2A) progenitor cells

AP-1 is an ubiquitous transcription factor which is composed of the Jun and Fos proto-oncogene proteins and is thought to play a role in both cell proliferation and differentiation. We have used an immortal, bipotential oligodendrocyte-type-2 astrocyte progenitor cell line (O-2A/c-myc) which can differentiate into oligodendrocytes or type-2 astrocytes in vitro, to investigate whether AP-1 DNA-binding activity fluctuates during glial cell differentiation. Unexpectedly, DNA-mobility shift assays using a TRE-containing oligonucleotide derived from the promoter of the glial-specific gene, glial fibrillary acidic protein (GFAP/AP-1), revealed that O-2A/c-myc progenitor cells were devoid of conventional AP-1 DNA-binding complexes. O-2A/c-myc cells did however contain several novel GFAP/AP-1-specific DNA-binding complexes, which we have termed APprog. APprog complexes recognise the TRE consensus motif present in the GFAP/AP-1 oligonucleotide together with adjacent 3′ sequences but do not contain c-Jun or any other known Jun-related proteins. When O-2A/c-myc cells underwent terminal differentiation APprog complexes were lost and conventional AP-1 DNA-binding activity became evident, particularly in astrocytes. These changes appear to be closely linked to the differentiation process since they did not occur in a derivative of the O-2A/c-myc cell line that contains an activated v-ras oncogene and which fails to differentiate under appropriate culture conditions. The inverse regulation of conventional AP-1 and APprog complexes within the O-2A lineage suggests that these factors may play a role in the regulation of glial cell differentiation or glial cell-specific gene expression.

AIDS prevention with adolescents

Prevention of human immunodeficiency virus (HIV) and acquired immunodeficiency syndrome (AIDS) among adolescents is increasingly recognized as an important public health priority. Sexual risk acts associated with HIV/AIDS transmission (unprotected sexual intercourse with multiple partners of unknown serostatus) are typically initiated by late adolescence, with many youths engaging in sexual relations earlier. Despite being well informed about HIV/AIDS and having positive attitudes toward HIV/AIDS prevention, adolescents have not changed their behavior in response to the pandemic. AIDS-prevention programs must be tailored to consider stereotypic sex roles, gay youths' sexual orientation, and substance abuse. Intensive prevention programs focusing on helping youths perceive HIV as a problem, motivate them to act safely, and implement safe acts by acquiring coping skills, access to condoms and health care, and identifying individual barriers to implementing safe acts have successfully reduced adolescents' risk acts. However, avenues for broad-scale dissemination of such programs or alternative models to change youths' behaviors must be identified.

Parent, teacher, and peer ratings of physically abused and nonmaltreated children's behavior

Behavior ratings by parents, teachers, and classmates of physically abused fourth to sixth graders, identified from the New York City Maltreatment Register, and case-matched classroom controls, showed substantial concurrence among informants: Parents and teachers both rated significantly more behavioral disturbance in the abused children, and peers' ratings were significantly correlated with adults' ratings, especially those by teachers. Children's exposure to spouse or partner physical abuse, which had a substantial prevalence among both child-abusing and control families, reduced the difference in disturbance ratings between children who were themselves physically abused and those who were not. Overall, we conclude that physically abused children show pervasive behavioral disturbance, in that parents, teachers, and classmates all see higher levels of behavior problems and lower levels of socially desirable behavior in them compared to their nonmaltreated peers.

Predicting patterns of sexual acts among homosexual and bisexual youths

OBJECTIVE

This longitudinal study examined predictors of patterns of change in HIV sexual risk acts among homosexual and bisexual adolescent males.

METHOD

A consecutive series of 136 homosexual and bisexual males aged 14-19 years were recruited into the study. Subjects were predominantly Hispanic (51%) and African American (31%) and seeking services at a homosexual-identified community-based agency in New York City. All subjects participated in an intensive HIV intervention program. Patterns of change in HIV sexual risk acts were based on assessments at four points (intake and 3, 6, and 12 months later) and were used to classify youths as demonstrating one of five patterns of anal and oral sexual acts: protected (anal: 45%, oral: 25%), improved (32% and 28%, respectively), relapse (5% and 8%), variable (8% and 15%), and unprotected (10% and 24%). Components of the health belief, self-efficacy, peer influence, coping, and distress models were assessed as predictors of these patterns.

RESULTS

Protected and improved patterns of sexual risk acts were associated with low levels of anxiety, depression, and substance use and high self-esteem.

CONCLUSIONS

These data suggest that HIV interventions must address non-HIV-related issues confronting youths in difficult life circumstances, particularly emotional distress and the role of peer networks for homosexual and bisexual youths.

Factors mediating changes in sexual HIV risk behaviors among gay and bisexual male adolescents

OBJECTIVES

Factors mediating changes in sexual behaviors that increase the risk of human immunodeficiency virus (HIV) infection were monitored in a group of gay and bisexual male adolescents.

METHODS

One hundred thirty-six males aged 14 to 19 years (Hispanic, 51%; African-American, 31%) were recruited from one gay-identified agency, were assessed at four points over a 1-year period, and participated in HIV preventive intervention sessions.

RESULTS

Significant reductions occurred in the number of unprotected same-sex anal and oral acts. Those with less risk in their previous sexual history, those who did not engage in commercial sex, and those who attended more HIV intervention sessions were more likely to reduce their sexual risk. The impact of sessions varied significantly by race/ethnicity: African-American youths reduced their risk acts most dramatically. Abstinence was consistently and significantly more likely among younger youths and those who had been abstinent before enrollment. The youths significantly reduced the number of sexual partners following the intervention; this reduction in partners was maintained through the 12-month follow-up and was greatest among youths with no involvement in commercial sexual activity (prostitution).

CONCLUSIONS

The efficacy of HIV prevention programs must be empirically evaluated.

Alcohol and drug use and sexual behaviors placing runaways at risk for HIV infection

Lifetime and current alcohol and drug use and sexual risk acts were examined among 154 male and 148 female runaways, aged 11-19, predominantly Black and Hispanic, residing at four residential shelters in the New York City area. Most runaways reported alcohol (71%) and drug use (46%), with about a quarter (27%) using either alcohol or drugs at least once a week during the past 3 months. Physical symptoms of substance abuse were reported by 47%; 17% reported addiction. Current substance use was higher among males and Hispanics, and increased with age. Substance use was significantly related to reporting more sexual partners and less frequent condom use. The results suggest that HIV/AIDS prevention programs must target the reduction of alcohol and drug use as well as sexual risk acts.

The effects of physical abuse on children's social relationships

Social behavior and peer status of 87 physically abused 8-12-year-old urban children were compared with those of 87 case-matched nonmaltreated classmates. Peer nominations and peer ratings were collected in classrooms, social networks were assessed by child interview, family variables were assessed by interviewing mothers, and behavior problems were rated by parents and teachers. Significant findings were that abused children had lower peer status and less positive reciprocity with peers chosen as friends; they were rated by peers as more aggressive and less cooperative and by parents and teachers as more disturbed; and their social networks showed more insularity, atypicality, and negativity. Social behavior as perceived by peers accounted for a significant portion of the variance in social status; global disturbance measures did not add to this association. Results are discussed in terms of a context of family violence in the development of social maladjustment.

Evaluation of a new tube latex agglutination test for detection of type-specific pneumococcal antigens in urine

A modified tube agglutination test using type-specific latex reagents for detection of pneumococcal capsular polysaccharide antigens in alkalinized, unconcentrated urine samples was evaluated in reconstituted urine samples and in groups consisting of 26 children with clinical and roentgenographic evidence of acute lower respiratory tract infection, six patients with blood culture-proven infection of nonpneumococcal etiology, and 30 healthy individuals. The sensitivity of the tube latex agglutination method for pneumococcal polysaccharides was 2 to 10 times higher than that of the slide agglutination method. Positive antigen findings were obtained for 42% of urine samples from patients with acute lower respiratory tract infection but in neither patients with nonpneumococcal septicemia nor healthy controls. Fifty-five percent of the antigen-positive patients also showed evidence of pneumococcal involvement by pneumococcal antibody assay or antigen detection in acute-phase serum.

Effects of ultrasound feedback on pregnancy anxiety, fetal activity, and neonatal outcome

A group of pregnant women received video and verbal feedback during three ultrasound examinations. This group was compared with a no-feedback group on measures of pregnancy anxiety, fetal activity, and neonatal outcome. The feedback appeared to reduce pregnancy anxiety and fetal activity, particularly for the primiparous women. These women also experienced fewer obstetric complications and gave birth to neonates who were greater weight, more appropriate weight-for-length, less active and irritable, and showed better performance on the Brazelton neonatal behavior assessment.

Coping with job stress and burnout in the human services

A mail survey of 141 human service workers investigated the effects of coping on psychological strain and "burnout" produced by job stress. The survey assessed job stressors and coping strategies with open-ended questions and measured strain using closed-ended alienation, satisfaction, and symptom scales. Because previous research suggested that individual coping responses do not alleviate strain produced by job stress, the survey elicited information on group coping (social support) and on coping strategies initiated by agencies. Job stress was associated with high levels of strain, and group coping with low levels, but individual responses had little effect. Although workers identified many strategies that agencies could use to reduce stress and strain, actual use of such strategies was slight. Because men and women worked in the same jobs, no sex differences in individual coping were predicted and none were found; women, however, reported more social support than men. There was no evidence for moderating (interaction) effects of stress and coping on strain.

Coping with job stress and burnout in the human services

A mail survey of 141 human service workers investigated the effects of coping on psychological strain and "burnout" produced by job stress. The survey assessed job stressors and coping strategies with open-ended questions and measured strain using closed-ended alienation, satisfaction, and symptom scales. Because previous research suggested that individual coping responses do not alleviate strain produced by job stress, the survey elicited information on group coping (social support) and on coping strategies initiated by agencies. Job stress was associated with high levels of strain, and group coping with low levels, but individual responses had little effect. Although workers identified many strategies that agencies could use to reduce stress and strain, actual use of such strategies was slight. Because men and women worked in the same jobs, no sex differences in individual coping were predicted and none were found; women, however, reported more social support than men. There was no evidence for moderating (interaction) effects of stress and coping on strain.

Effects of pH, temperature, aeration and carbon source on the development of the mycelial or yeast forms of Sporothrix schenckii from conidia

Culture conditions for the exclusive development of the mycelial and the yeast forms of Sporothrix schenckii from conidia in a rich, defined medium were established. Only the mycelial morphology developed when the pH of the medium was adjusted between 4.0 and 5.0 and the conidia were incubated at 25 degrees C, regardless of aeration. When the pH of the medium was adjusted between 6.5 and 8.0 and the conidia were incubated with aeration at 35 degrees C, only the yeast form was obtained. Using these culture conditions conidia were inoculated in a buffered-salts medium with vitamins with or without added carbohydrates as carbon sources. After incubation, the form obtained was recorded and the amount of growth determined on a dry weight basis. Development of the mycelial form was observed with all of the carbon sources tested (glucose, fructose, mannose, arabinose, maltose, sucrose and starch) while the yeast form developed only when glucose or another hexose was added to the medium. These observations indicated that in S. schenckii the development of conidia into a specific form is dependent on the interrelationship between the available nutrients and the culture conditions and that no specific parameter seemed to be exclusively determinant of the morphology obtained.

Epidermoid tumors involving the fourth ventricle

The case histories of three patients with epidermoid tumors of the 4th ventricle treated by surgical excision are presented. All three cases exhibited a prolonged latent period from the onset of symptoms to the final diagnosis. Despite the strategic location and enormous size of all three tumors, only one of the patients had significant hydrocephalus. The radiographic diagnosis and differential diagnosis of epidermoid tumors are discussed.