Postoperative Radiotherapy for Cutaneous Melanoma in Patients at High Risk of Local-Regional Recurrence after Surgery Alone

We evaluated outcomes in 131 patients with cutaneous melanoma (median follow-up, 3.6 years) considered at high risk of recurrence after surgery alone treated with surgery and postoperative radiotherapy. Eligible patients had one or more of the following: recurrence after surgery, positive lymph nodes, extracapsular extension, incomplete regional node dissection, microscopically positive margins, gross residual disease, or in-transit metastases. 102 patients received hypofractionated radiotherapy and 29 had conventional fractionation. 10-year outcomes were: in-field local-regional control, 87%; local regional control, 72%; distant metastasis-free survival, 48%; cause-specific survival, 44%; and overall survival, 31%. Three patients experienced acute toxicities while 6 experienced late toxicities.

Hyperfractionated-Accelerated Reirradiation with Proton Therapy for Radiation-Associated Breast Angiosarcoma

Purpose

Radiation-associated angiosarcoma (RAAS) is a rare complication among patients treated with radiation therapy for breast cancer. Hyperfractionated-accelerated reirradiation (HART) improves local control after surgery. Proton therapy may further improve the therapeutic ratio by mitigating potential toxicity.

Materials and Methods

Six patients enrolled in a prospective registry with localized RAAS received HART with proton therapy between 2015 and 2021. HART was delivered twice or thrice daily in fraction sizes of 1.5 or 1.0 Gy, respectively. All patients received 45 Gy to a large elective volume followed by boosts to a median dose of 65 (range, 60-75) Gy. Toxicity was recorded prospectively by using the Common Terminology Criteria for Adverse Events, version 4.0.

Results

The median follow-up duration was 1.5 (range, 0.25-2.9) years. The median age at RAAS diagnosis was 73 (range, 60-83) years with a median latency of 8.9 (range, 5-14) years between radiation therapy completion and RAAS diagnosis. The median mean heart dose was 2.2 (range, 0.1-4.96) Gy. HART was delivered postoperatively (n = 1), preoperatively (n = 3), preoperatively for local recurrence after initial management with mastectomy (n = 1), and as definitive treatment (n = 1). All patients had local control of disease throughout follow-up. Three of 4 patients treated preoperatively had a pathologic complete response. The patient treated definitively had a complete metabolic response on her posttreatment PET/CT (positron emission tomography–computed tomography) scan. Two patients developed distant metastatic disease despite local control and died of their disease. Acute grade 3 toxicity occurred in 3 patients: 2 patients undergoing preoperative HART experienced wound dehiscence and 1 postoperatively developed grade 3 wound infection, which resolved.

Conclusion

HART with proton therapy appears effective for local control of RAAS with a high rate of pathologic complete response and no local recurrences to date. However, vigilant surveillance for distant metastasis should occur. Toxicity is comparable to that in photon/electron series. Proton therapy for RAAS may maximize normal tissue sparing in this large-volume reirradiation setting.

Five-Year Breast Surgeon Experience in LYMPHA at Time of ALND for Treatment of Clinical T1-4N1-3M0 Breast Cancer

BACKGROUND

Breast cancer-related lymphedema (BCRL) is a source of postoperative morbidity for breast cancer survivors. Lymphatic microsurgical preventive healing approach (LYMPHA) is a technique used to prevent BCRL at the time of axillary lymph node dissection (ALND). We report the 5-year experience of a breast surgeon trained in LYMPHA and investigate the outcomes of patients who underwent LYMPHA following ALND for treatment of cT1-4N1-3M0 breast cancer.

METHODS

A retrospective review of patients with cT1-4N1-3M0 breast cancer was performed in patients who underwent ALND with and without LYMPHA. Diagnosis of BCRL was made by certified lymphedema therapists. Descriptive statistics and lymphedema surveillance data were analyzed using results of Fisher's exact or Wilcoxon rank-sum tests. Logistic regression and propensity matching were performed to assess the reduction of BCRL occurrence following LYMPHA.

RESULTS

In a 5-year period, 132 patients met inclusion criteria with 76 patients undergoing LYMPHA at the time of ALND and 56 patients undergoing ALND alone. Patients who underwent LYMPHA at the time of ALND were significantly less likely to develop BCRL than those who underwent ALND alone (p = 0.045). Risk factors associated with BCRL development were increased patient age (p = 0.007), body mass index (BMI) (p = 0.003), and, in patients undergoing LYMPHA, number of positive nodes (p = 0.026).

CONCLUSIONS

LYMPHA may be successfully employed by breast surgeons trained in lymphatic-venous anastomosis at the time of ALND. While research efforts should continue to focus on prevention and surveillance of BCRL, LYMPHA remains an option to reduce BCRL and improve patient quality of life.

Performance Improvement With Implementation of a Surgical Skills Curriculum

OBJECTIVE

To assess the efficacy of an intern surgical skills curriculum involving a boot camp for core open and laparoscopic skills, self-guided practice with positive and negative incentives, and semiannual performance evaluations.

DESIGN

Longitudinal cohort study.

SETTING

Academic tertiary care center.

PARTICIPANTS

Intervention group (n = 15): residents who completed the intern surgical skills curriculum and had performance evaluations in fall of intern year, spring of intern year, and fall of second year. Control group (n = 8): second-year residents who were 1 year ahead of the intervention group in the same residency program, did not participate in the curriculum, and had performance evaluations in fall of second year.

RESULTS

In fall of second year of residency, the intervention group had better performance (presented as median values with interquartile ranges) than the control group on one-hand ties (left hand: 9.1 [6.3-10.1] vs 14.6 [13.5-15.4] seconds, p = 0.007; right hand: 8.7 [8.5-9.6] vs 11.5 [9.9-16.8] seconds, p = 0.039). The intervention group also had better performance on all open suturing skills, including mattress suturing (vertical: 33.4 [30.0-40.0] vs 55.8 [50.0-67.6] seconds, p = 0.001; horizontal: 28.7 [27.3-39.9] vs 52.7 [40.7-57.8] seconds, p = 0.003), and a water-filled glove clamp, divide, and ligate task (28.0 [25.0-31.0] vs 59.1 [53.0-93.0] seconds, p < 0.001). Finally, the intervention group had better performance on all laparoscopic skills, including peg transfer (66.0 [59.0-82.0] vs 95.2 [87.5-101.5] seconds, p = 0.018), circle cut (82.0 [69.0-124.0] seconds vs 191.8 [155.5-231.5] seconds, p = 0.002), and intracorporeal suturing (195.0 [117.0-200.0] seconds vs 359.5 [269.0-450.0] seconds, p = 0.002).

CONCLUSIONS

Implementation of a comprehensive surgical skills curriculum was associated with improved performance on core open and laparoscopic skills. Further research is needed to understand and optimize motivational factors for deliberate practice and surgical skill acquisition.

Associations Between National Board Exam Performance and Residency Program Emphasis on Patient Safety and Interprofessional Teamwork

OBJECTIVE

Several aspects of medical training may contribute to the ultimate goal of producing excellent physicians whose patients will have the best possible outcomes. However, the relative importance of education, evaluation and feedback, duty hours, practice structure, and program culture in achieving this goal is unclear. This study assessed associations among in-training exam performance, Accreditation Council for Graduate Medical Education (ACGME) Resident Survey responses, and American Board of Medical Specialties (ABMS) national board exam performance.

METHODS

Residency training programs at a university teaching hospital were classified as having 5-year first-time ABMS pass rates above (n=12) or below (n=3) the national average for their specialty. These groups were compared by ACGME Resident Survey data and in-training exam performance.

RESULTS

Surveys were collected from 484/543 eligible residents (89%), including 177 surveys from programs with below-average board pass rates and 307 surveys from programs with aboveaverage board pass rates. In-training exam performance was similar between groups. Aboveaverage programs had stronger agreement with statements that their culture reinforced patient safety (4.72 vs. 4.30, p=0.006) and that information was not lost during transitions of care (4.14 vs. 3.63, p=0.001). Although the occurrence of interprofessional teamwork was similar between groups, above-average programs had stronger agreement with the statement that interprofessional teamwork was effective (4.60 vs. 4.17, p=0.003).

CONCLUSION

Residency programs emphasizing patient safety and effective interprofessional teamwork had above-average first-time national board pass rates.

Prognostic Value of Clinical vs Pathologic Stage in Rectal Cancer Patients Receiving Neoadjuvant Therapy

Background

Neoadjuvant chemoradiation is currently standard of care in stage II-III rectal cancer, resulting in tumor downstaging for patients with treatment-responsive disease. However, the prognosis of the downstaged patient remains controversial. This work critically analyzes the relative contribution of pre- and post-therapy staging to the anticipated survival of downstaged patients.

Methods

The National Cancer Database (NCDB) was queried for patients with rectal cancer treated with transabdominal resection between 2004 and 2014. Stage II-III patients downstaged with neoadjuvant radiation were compared with stage I patients treated with definitive resection alone. Patients with positive surgical margins were excluded. Overall survival was evaluated using both Kaplan-Meier analyses and Cox proportional hazards models. All statistical tests were two-sided.

Results

A total of 44 320 patients were eligible for analysis. Survival was equivalent for patients presenting with cT1N0 disease undergoing resection (mean survival = 113.0 months, 95% confidence interval [CI] = 110.8 to 115.3 months) compared with those downstaged to pT1N0 from both cT3N0 (mean survival = 114.9 months, 95% CI = 110.4 to 119.3 months, P = .12) and cT3N1 disease (mean survival = 115.4 months, 95% CI = 110.1 to 120.7 months, P = .22). Survival statistically significantly improved in patients downstaged to pT2N0 from cT3N0 disease (mean survival = 109.0 months, 95% CI = 106.7 to 111.2 months, P < .001) and cT3N1 (mean survival = 112.8 months, 95% CI = 110.0 to 115.7 months, P < .001), compared with cT2N0 patients undergoing resection alone (mean survival = 100.0 months, 95% CI = 97.5 to 102.5 months). Multiple survival analysis confirmed that final pathologic stage dictated long-term outcomes in patients undergoing neoadjuvant radiation (hazard ratio [HR] of pT2 = 1.24, 95% CI = 1.10 to 1.41; HR of pT3 = 1.81, 95% CI = 1.61 to 2.05; HR of pT4 = 2.72, 95% CI = 2.28 to 3.25, all P ≤ .001 vs pT1; HR of pN1 = 1.50, 95% CI = 1.41 to 1.59; HR of pN2 = 2.17, 95% CI = 2.00 to 2.35, both P < .001 vs pN0); while clinical stage at presentation had little to no predictive value (HR of cT2 = 0.81, 95% CI = 0.69 to 0.95, P = .008; HR of cT3 = 0.83, 95% CI = 0.72 to 0.96, P = .009; HR of cT4 = 1.02, 95% CI = 0.85 to 1.21, P = .87 vs cT1; HR of cN1 = 0.96, 95% CI = 0.91 to 1.02, P = .19; HR of cN2 = 0.96, 95% CI = 0.86 to 1.08, P = .48 vs cN0).

Conclusions

Survival in patients with rectal cancer undergoing neoadjuvant radiation is driven by post-therapy pathologic stage, regardless of pretherapy clinical stage. These data will further inform prognostic discussions with patients.

Gender Diversity in General Surgery Residency Leadership

OBJECTIVE

This study aimed to evaluate the proportion and characteristics of women who serve in general surgery program director (PD) and associate program director (APD) positions in the United States.

DESIGN

General surgery programs (n = 276) and directors were identified using the Association for Program Directors in Surgery website; information was cross-referenced with American Medical Association FREIDA and Accreditation Council for Graduate Medical Education databases, current to July 1, 2017. Each program's website was accessed to determine the gender and academic ranking of faculty.

RESULTS

Results reveal a preponderance of men in PD and APD positions. Women accounted for 18.4% (n = 51) of the 276 PD positions, with more women in APD positions (29.6%). There was no correlation between gender of PD and the corresponding APD, (χ2 = 0.68, p = 0.41; Phi coefficient = -0.0695). Of those with academic appointments, men who were PDs were more likely to be full professors when compared to women PDs (38.5% vs 24.1%, respectively). The median number of days since appointment to PD was similar in both groups (1461 days for men vs 1377 for women, p = 0.18), although more men have held PD positions longer. Programs with a higher proportion of women faculty were more likely to have a woman PD (p = 0.0397), but not those with more women residents (p = 0.225) or a woman Department Chair (p = 0.56).

CONCLUSIONS

Among general surgery program directorship, men continue to hold more positions of educational leadership, although the trend appears to be shifting toward a more equal balance, particularly in those programs with proportionately more women faculty. This discrepancy may be due to academic rank or length of tenure. As more women hold academic positions in the field of general surgery, an increase in the representation of this group in leadership is anticipated. Although senior leadership (PD) positions remain disproportionately held by men, APD positions are filled by a greater percentage of women than academic surgical faculty, although the absolute percentage remains less than 50%. Educational leadership may be a viable path to academic leadership for both women and men.

Rectal cancer patients younger than 50 years lack a survival benefit from NCCN guideline-directed treatment for stage II and III disease

BACKGROUND

The incidence of rectal cancer in patients younger than 50 years is increasing. To test the hypothesis that the biology in this younger cohort may differ, this study compared survival patterns, stratifying patients according to National Comprehensive Cancer Network (NCCN) guideline-driven care and age.

METHODS

The National Cancer Data Base was queried for patients treated with curative-intent transabdominal resections with negative surgical margins for stage I to III rectal cancer between 2004 and 2014. Outcomes and overall survival for patients younger than 50 years and patients 50 years old or older were compared by subgroups based on NCCN guideline-driven care.

RESULTS

A total of 43,106 patients were analyzed. Younger patients were more likely to be female and minorities, to be diagnosed at a higher stage, and to have travelled further to be treated at academic/integrated centers. Short- and long-term outcomes were significantly better for patients younger than 50 years, with age-specific survival rates calculated. Younger patients were more likely to receive radiation treatment outside NCCN guidelines for stage I disease. In younger patients, the administration of neoadjuvant chemoradiation for stage II and III disease was not associated with an overall survival benefit.

CONCLUSIONS

Age-specific survival data for patients with rectal cancer treated with curative intent do not support an overall survival benefit from NCCN guideline-driven therapy for stage II and III patients younger than 50 years. These data suggest that early-onset disease may differ biologically and in its response to multimodality therapy.

Non-surgical management of patients with intrahepatic cholangiocarcinoma in the United States, 2004-2015: an NCDB analysis

Background

Surgical resection is the standard of care for intrahepatic cholangiocarcinoma (ICC), but only a minority of patients are managed surgically. Other modalities, including external beam radiation (XRT), radiofrequency ablation (RFA), and radioactive implants (RIs) have been employed with significant heterogeneity of prognosis reported in the literature. The aim of this study was to evaluate the demographics of patients with ICC managed non-surgically and compare prognosis in patients managed surgically to those that underwent XRT, RFA, or RI.

Methods

All patients diagnosed with ICC from 2004 to 2015 in the National Cancer Database (NCDB) were reviewed. Patient demographics, treatments, and survival outcomes were analyzed.

Results

Of the 6,140 patients with ICC, 4,374 (71%) did not undergo surgery. Patients managed non-surgically were typically older, treated at community centers, more likely to have severe fibrosis or cirrhosis, and present with higher stage disease. The strongest association to receipt of XRT, RI, or RFA modalities was treatment at an academic center. Increased clinical stage was associated with decreased use of RFA; a significantly higher proportion of patients with stage IV disease were given no local therapy. RFA associated with a statistically significant survival benefit over no local therapy only in stage I disease (2.1 vs. 0.7 years, P=0.012) as well as XRT over no local therapy (1.7 vs. 0.7 years, P=0.009). No survival benefit was realized for any treatment in stage II disease. Patients with stage III disease had a survival benefit from XRT versus no local therapy (0.9 vs. 0.6 years, P=0.029) and RI over no local therapy (1.2 vs. 0.6 years, P=0.013). Patients with stage IV disease only demonstrated survival benefit from RI over no local therapy (0.9 vs. 0.3 years, P=0.014).

Conclusions

The majority of patients with ICC in the United States continue to be managed non-surgically. RFA was associated with improved survival only in stage I disease. XRT was associated with improved survival in stage I & III disease, while RI was associated with improved survival in stage III and IV disease.

Bonobos Maintain Immune System Diversity with Three Functional Types of MHC-B

Fast-evolving MHC class I polymorphism serves to diversify NK cell and CD8 T cell responses in individuals, families, and populations. Because only chimpanzee and bonobo have strict orthologs of all HLA class I, their study gives unique perspectives on the human condition. We defined polymorphism of Papa-B, the bonobo ortholog of HLA-B, for six wild bonobo populations. Sequences for Papa-B exon 2 and 3 were determined from the genomic DNA in 255 fecal samples, minimally representing 110 individuals. Twenty-two Papa-B alleles were defined, each encoding a different Papa-B protein. No Papa-B is identical to any chimpanzee Patr-B, human HLA-B, or gorilla Gogo-B. Phylogenetic analysis identified a clade of MHC-B, defined by residues 45-74 of the α₁ domain, which is broadly conserved among bonobo, chimpanzee, and gorilla. Bonobo populations have 3-14 Papa-B allotypes. Three Papa-B are in all populations, and they are each of a different functional type: allotypes having the Bw4 epitope recognized by killer cell Ig-like receptors of NK cells, allotypes having the C1 epitope also recognized by killer cell Ig-like receptors, and allotypes having neither epitope. For population Malebo, these three Papa-B are the only Papa-B allotypes. Although small in number, their sequence divergence is such that the nucleotide diversity (mean proportional distance) of Papa-B in Malebo is greater than in the other populations and is also greater than expected for random combinations of three Papa-B Overall, Papa-B has substantially less diversity than Patr-B in chimpanzee subspecies and HLA-B in indigenous human populations, consistent with bonobo having experienced narrower population bottlenecks.

Resistance to type 1 interferons is a major determinant of HIV-1 transmission fitness

Sexual transmission of HIV-1 is an inefficient process, with only one or few variants of the donor quasispecies establishing the new infection. A critical, and as yet unresolved, question is whether the mucosal bottleneck selects for viruses with increased transmission fitness. Here, we characterized 300 limiting dilution-derived virus isolates from the plasma, and in some instances genital secretions, of eight HIV-1 donor and recipient pairs. Although there were no differences in the amount of virion-associated envelope glycoprotein, recipient isolates were on average threefold more infectious (P = 0.0001), replicated to 1.4-fold higher titers (P = 0.004), were released from infected cells 4.2-fold more efficiently (P < 0.00001), and were significantly more resistant to type I IFNs than the corresponding donor isolates. Remarkably, transmitted viruses exhibited 7.8-fold higher IFNα2 (P < 0.00001) and 39-fold higher IFNβ (P < 0.00001) half-maximal inhibitory concentrations (IC50) than did donor isolates, and their odds of replicating in CD4+ T cells at the highest IFNα2 and IFNβ doses were 35-fold (P < 0.00001) and 250-fold (P < 0.00001) greater, respectively. Interestingly, pretreatment of CD4+ T cells with IFNβ, but not IFNα2, selected donor plasma isolates that exhibited a transmitted virus-like phenotype, and such viruses were also detected in the donor genital tract. These data indicate that transmitted viruses are phenotypically distinct, and that increased IFN resistance represents their most distinguishing property. Thus, the mucosal bottleneck selects for viruses that are able to replicate and spread efficiently in the face of a potent innate immune response.

Improved Breast Cancer Care Quality Metrics After Implementation of a Standardized Tumor Board Documentation Template

PURPOSE

Cancer treatment requires a coordinated multidisciplinary treatment approach, which led to the development of the Rapid Quality Reporting System by the Commission on Cancer. However, the lack of immediate availability of documented treatment plans and the inefficiency of global medical record reviews represent significant barriers to adherence reporting and the timely implementation of quality improvement measures.

METHODS

Adherence to national guidelines in the areas of radiation treatment, chemotherapy, and hormone therapy was assessed after breast conservation surgery (BCS). Adherence rates within 1 year of BCS were analyzed 10 weeks before and after the implementation of a standardized documentation template at weekly multidisciplinary breast cancer conferences.

RESULTS

Documented adherence rates increased postimplementation in patients undergoing consideration for both radiation treatment and hormone therapy within 1 year of BCS (89% v 65%; P = .045% and 85% v 62%; P = .002, respectively). No change was observed in patients undergoing evaluation for cytotoxic chemotherapy (80% v 85%; P = 1.00).

CONCLUSION

The addition of a documentation template to multidisciplinary breast cancer conferences resulted in increased recorded adherence rates to national guidelines. This template provided a means of both accurate and efficient documentation of evidence-based practice, which represents a concept with broad application in quality improvement. Although evaluation of the project was not continued beyond the pilot stage, current quality measure scores remain within the same range.

Cylindroma-like basaloid anal cancer presenting as a large pelvic mass in a patient with ulcerative colitis

Basaloid cancers of the lower gastrointestinal tract are rare. The lack of mucosal involvement of this type of tumor is uncharacteristic and, to our knowledge, has not been described. In addition, the cylindroma-like appearance of this cancer has only a few examples in the literature. A 51-year-old male presented to us with a history of ulcerative colitis (UC) and obstruction of the anal canal. Imaging and colonoscopy revealed an entirely extraluminal tumor. Percutaneous biopsy yielded a diagnosis of cylindroma-like basaloid carcinoma of the anal region. Neoadjuvant chemotherapy and radiation resulted in stable disease by RECIST criteria. Surgical planning ensued, which led to R0 resection of the tumor, total colectomy and end ileostomy for his UC, and reconstruction of the perineal defect with a rectus myocutaneous flap. Surveillance at 6 months demonstrated no evidence of disease.

Integration of mobile technology in educational materials improves participation: creation of a novel smartphone application for resident education

OBJECTIVE

Traditional education consists of didactics and book learning. Recently, technology has been integrated into graduate medical education, primarily in the form of simulation. The primary aim of this study was to investigate if a novel smartphone application using technology to engage learners would improve participation in an educational activity when compared with a daily e-mail format and how this use translated to performance on standardized testing.

DESIGN

The UF Surgery App (App), which is a smartphone application, was developed to deliver 2 questions from a general surgery educational database every weekday from October to February 2013. The App, developed for iOS, featured a notification alarm and a reminder icon to actively engage the learner. Learners who used the App responded to multiple-choice questions and were provided instantaneous feedback in the form of a correct answer with an explanation. The response rate and answers were collected prospectively and compared with the American Board of Surgery In-Training Examination score.

SETTING

University of Florida, College of Medicine, Gainesville, Florida, a university teaching hospital.

PARTICIPANTS

A total of 46 general surgical residents were enrolled in a university training program. Participation was voluntary.

RESULTS

Overall, 26 of 46 (57%) residents participated. Of the users, 70% answered more than 20% of the questions, while 46% responded to more than 70% of questions. The percentage of correct answers on the App was positively correlated with standardized score (p = 0.005), percentage correct (p = 0.02), and percentile (p = 0.034) on the ABSITE examination.

CONCLUSIONS

Technology can be used to actively engage residents. Deployment of this novel App improved participation over a daily question-answer e-mail format, and answers correlated with standardized test performance. The effect of the App on overall education is unclear, and a multi-institutional study has been initiated.

Phytotoxicity induced in isolated zooxanthellae by herbicides extracted from Great Barrier Reef flood waters

To date there has been limited evidence anthropogenically sourced pollution from catchments reaching corals of the Great Barrier Reef (GBR). In this study, freshly isolated zooxanthellae were exposed to polar chemicals (chiefly herbicides) extracted from water samples collected in a flood plume in the GBR lagoon. Photosynthetic potential of the isolated zooxanthellae declined after exposure to concentrated extracts (10 times) from all but one of the sampling sites. Photosynthetic potential demonstrated a significant positive relationship with the concentration of diuron in the concentrated extracts and a significant inverse relationship with salinity measured at the sampling site. This study demonstrates that runoff from land based application of herbicides may reduce photosynthetic efficiency in corals of inshore reefs in the GBR. The ecological impacts of the chemicals in combination with other potential stressors on corals remain unclear.

Elevated expression of IRS2 in the progression from neurofibroma to malignant peripheral nerve sheath tumor

BACKGROUND/AIM

Novel drugs to inhibit insulin receptor substrate (IRS) and focal adhesion kinase (FAK) pathways are emerging and will be sarcoma subtype-specific. As a result, defining expression of proteins in these pathways; in select tumors is important in order to formulate therapeutic approaches to malignant peripheral nerve sheath tumors (MPNSTs).

MATERIALS AND METHODS

Fifty-three patients with MPNSTs or neurofibromas (NFs), who were treated at our institution from 1994-2005, were identified. Tumor immonohistochemical staining for multiple key oncogenic proteins was performed and the sections were evaluated in a blinded fashion by a sarcoma pathologist (JDR) and correlated with survival.

RESULTS

A total of 88% of MPNSTs expressed IRS2 compared to 48% of NFs. IRS2 expression was significantly higher in MPNSTs than in NFs (p=0.0009). However, IRS1 expression was significantly higher in NFs than MPNSTs (p=0.03). A trend toward an increase in FAK expression in MPNSTs was seen (p=0.11). No difference was seen between MPNSTs and NFs when evaluating the expression of phosphorylated focal adhesions kinase, vascular endothelial growth factor 3, insulin like growth factor receptor 1, neurofibromatosis 1. Univariate analysis of survival indicated that IRS2 and NF1 protein expression, patient age and tumor size were significantly correlated with outcome.

CONCLUSION

MPNSTs have an elevated level of IRS2 and FAK and lower level of IRS1 compared to NFs These data demonstrate for the first time that IRS2 and FAK may be associated with malignant transformation of neurofibromas.

Prospective case-control study of serum mullerian inhibiting substance and breast cancer risk

Background

Müllerian inhibiting substance (MIS) is a member of the transforming growth factor β family of growth and differentiation factors that inhibits elongation and branching of mammary ducts and has been shown to inhibit mammary tumor growth in vitro and in animal models. The objective of this study was to determine whether serum MIS levels are associated with breast cancer risk.

Methods

We conducted a prospective case–control study of 309 participants who were registered in the Columbia, Missouri Serum Bank. Each of 105 in situ or invasive breast cancer case patients with prediagnostic serum collected before menopause was matched to two control subjects by age, date, menstrual cycle day, and time of day of blood collection. MIS was measured in serum by using an enzyme-linked immunosorbent assay, and estradiol and testosterone concentrations were quantified by using specific radioimmunoassays. Data were analyzed using conditional logistic regression. All tests of statistical significance were two-sided.

Results

The relative odds ratio of breast cancer for women in increasing MIS quartiles were 1, 2.8 (95% confidence interval [CI] = 1.0 to 7.4), 5.9 (95% CI = 2.4 to 14.6), and 9.8 (95% CI = 3.3 to 28.9, P_trend < .001). The association of MIS with breast cancer was weaker in women who were not taking oral contraceptives at the time of blood collection, but adjustment for estradiol and testosterone levels did not materially alter results for these women. The association of MIS with breast cancer did not vary by age at blood collection but was stronger among women who were diagnosed with breast cancer at an older age than among those who were diagnosed at a younger age.

Conclusion

MIS may be a novel biomarker of increased breast cancer risk. Additional research including confirmatory epidemiological studies and mechanistic studies is needed.

Assay reproducibility and within-person variation of Müllerian inhibiting substance

OBJECTIVES

To assess reproducibility of a commercial müllerian inhibiting substance (MIS) assay and evaluate within-person variation in serum MIS levels.

DESIGN

Assay reproducibility was evaluated by measuring MIS in multiple serum aliquots from the same blood collection. Within-person variation was assessed by measuring MIS in serum collected twice from the same individuals.

SETTING

Cancer Prevention Biomarker and Genotyping Facility, fox Chase Cancer Center, Philadelphia, Pennsylvania.

PATIENT(S)

Assay reproducibility was evaluated using serum from five volunteers with regular menstrual cycles. Within-person variation was evaluated in serum from 20 premenopausal women who donated blood twice at least 1 year apart.

INTERVENTION(S)

For both studies, samples were randomly ordered in batches and laboratory personnel were blinded to which aliquots were from the same subject.

MAIN OUTCOME MEASURE(S)

The MIS was measured by ELISA.

RESULT(S)

Within- and between-batch coefficients of variation (CVs) of the assay were 7.9% and 12.3%, respectively. After deleting one subject with extreme values, these CVs decreased to 7.6% and 7.7%, respectively. Within- and between-subject variance in MIS measurements were 2.19 and 0.31, respectively, and the intraclass correlation coefficient was 0.88 (95% confidence interval .77-.98).

CONCLUSION(S)

The MIS serum concentration is relatively stable over 1 year in premenopausal women and can be measured with good reproducibility using a commercial kit.

Functional enhancement of CFTR expression by mitomycin C

Cystic fibrosis is caused by mutations in the CFTR gene. The most common of these mutations, DeltaF508, results in a protein that is not trafficked to the apical plasma membrane but instead is retained and degraded in the endoplasmic reticulum (ER) by the 26S proteosome. However, this protein is functional upon plasma membrane expression. It has been theoretically estimated that even a modest ( approximately 10%) increase in CFTR-associated chloride conductance can be beneficial in a clinical setting. Thus, understanding basic CFTR biogenesis is important, and identification of prototypical compounds that can increase CFTR expression and trafficking is potentially useful in the development of novel therapeutic strategies to treat cystic fibrosis. We report that mitomycin C (MMC) elicits such a response by increasing CFTR mRNA and protein expression in T-84 and HT-29 cells at very low, non-cytotoxic, pharmacologically relevant concentrations (0.1 microM) leading to enhanced chloride secretion. Thus, MMC may be a useful compound for understanding CFTR regulation and biogenesis.

Increased functional cell surface expression of CFTR and DeltaF508-CFTR by the anthracycline doxorubicin

Cystic fibrosis (CF) is a disease that is caused by mutations within the cystic fibrosis transmembrane conductance regulator (CFTR) gene. The most common mutation, DeltaF508, accounts for 70% of all CF alleles and results in a protein that is defective in folding and trafficking to the cell surface. However, DeltaF508-CFTR is functional when properly localized. We report that a single, noncytotoxic dose of the anthracycline doxorubicin (Dox, 0.25 microM) significantly increased total cellular CFTR protein expression, cell surface CFTR protein expression, and CFTR-associated chloride secretion in cultured T84 epithelial cells. Dox treatment also increased DeltaF508-CFTR cell surface expression and DeltaF508-CFTR-associated chloride secretion in stably transfected Madin-Darby canine kidney cells. These results suggest that anthracycline analogs may be useful for the clinical treatment of CF.

Solitary eosinophilic granuloma of the temporal lobe: case report and review of the literature

A solitary eosinophilic granuloma of the central nervous system is an unusual manifestation of histiocytosis X. A unique case of a solitary eosinophilic granuloma of the right temporal lobe without osseous involvement is described. A 20-year-old man presented with a grand mal seizure. Magnetic resonance imaging demonstrated an intraaxial enhancing mass in the right temporal lobe with marked vasogenic edema. A right temporal craniotomy was performed for resection of the lesion and the diagnosis of an eosinophilic granuloma was confirmed by histopathology. Follow-up MR imaging obtained 5 years following resection demonstrated no recurrence. Solitary eosinophilic granuloma should be considered in the differential diagnosis of enhancing mass lesions affecting the central nervous system. Although the natural history of solitary eosinophilic granulomas remains poorly defined, surgical treatment still remains the mainstay of therapy for these unifocal cerebral lesions.

Familial dementia caused by polymerization of mutant neuroserpin

Aberrant protein processing with tissue deposition is associated with many common neurodegenerative disorders; however, the complex interplay of genetic and environmental factors has made it difficult to decipher the sequence of events linking protein aggregation with clinical disease. Substantial progress has been made toward understanding the pathophysiology of prototypical conformational diseases and protein polymerization in the superfamily of serine proteinase inhibitors (serpins). Here we describe a new disease, familial encephalopathy with neuroserpin inclusion bodies, characterized clinically as an autosomal dominantly inherited dementia, histologically by unique neuronal inclusion bodies and biochemically by polymers of the neuron-specific serpin, neuroserpin. We report the cosegregation of point mutations in the neuroserpin gene (PI12) with the disease in two families. The significance of one mutation, S49P, is evident from its homology to a previously described serpin mutations, whereas that of the other, S52R, is predicted by modelling of the serpin template. Our findings provide a molecular mechanism for a familial dementia and imply that inhibitors of protein polymerization may be effective therapies for this disorder and perhaps for other more common neurodegenerative diseases.

Recurrent intracranial Masson's vegetant intravascular hemangioendothelioma. Case report and review of the literature

In the central nervous system, recurrence of intracranial Masson's vegetant intravascular hemangioendothelioma (MVIH) is rare. To the authors' knowledge, only three recurrent intracranial cases have been reported. The authors report the case of a 75-year-old woman with a recurrent left-sided cerebellopontine angle and middle cranial fossa MVIH. When the patient was 62 years of age, she underwent preoperative embolization and subtotal resection of the intracranial lesion followed by postoperative radiotherapy. She was well and free from disease until 9 years postoperatively when she became symptomatic. At 71 years of age, the patient again underwent preoperative embolization and near-gross-total resection of the lesion. Follow-up imaging performed 15 months later revealed tumor recurrence, and she underwent stereotactic gamma knife radiosurgery. At a 2.75-year follow-up review, the patient's imaging studies revealed stable residual tumor. This case report is unique in that it documents the clinical and pathological features, surgical and postoperative treatment, and long-term follow-up review of a patient with recurrent intracranial MVIH and suggests that this unusual vascular lesion is a slow-growing benign tumor rather than a reactive process. Because the pathological composition of the lesion may resemble an angiosarcoma, understanding this benign vascular neoplasm is crucial so that an erroneous diagnosis of malignancy is not made and unnecessary adjuvant therapy is not given.

Prevalence of anxiety and depressive illness and help seeking behaviour in African Caribbeans and white Europeans: two phase general population survey

OBJECTIVE

To determine the prevalence of common mental disorders (anxiety and depression) and help seeking behaviour in African Caribbeans and white Europeans.

DESIGN

Two phase survey in a general population sample. The first phase comprised screening with the 12 item general health questionnaire; the second phase was standardised psychiatric assessment and interview about help seeking.

SETTING

People registered with four general practices in central Manchester.

PARTICIPANTS

Of 1467 people randomly selected from family health services authority lists, 864 were still resident. 337 African Caribbeans and 275 white Europeans completed the screening phase (response rate 71%); 127 African Caribbeans and 103 white Europeans were interviewed in the second phase.

MAIN OUTCOME MEASURES

One month period prevalence of anxiety and depressive disorders in each ethnic group.

RESULTS

13% of African Caribbeans (95% confidence interval 10% to 16%) and 14% (10% to 18%) of white Europeans had one or more disorder. Anxiety disorders were significantly less common among African Caribbeans (3% (1% to 5%) v 9% (6% to 12%) in white Europeans). Depressive disorders were significantly more common among African Caribbean women than white women (difference 8% (1% to 15%)). Medical help seeking was similar in the two groups, but African Caribbeans with mental disorders were more likely to seek additional help from non-medical sources (12/29 v 5/29, P=0.082).

CONCLUSIONS

In an inner city setting the prevalence of common mental disorders is similar in these two ethnic groups.

Surgical management and seizure outcome in patients with tuberous sclerosis

The authors report the results obtained in 11 patients with tuberous sclerosis (TS) who underwent cortical resection surgery for medically intractable epilepsy. Patients' ages at time of surgery ranged from 3 to 46 years (mean 19.6 years). Preoperative epileptiform electroencephalographic abnormalities were focal spike wave discharges in six patients (55%), multifocal in four patients (36%), and generalized in one patient (9%). In the multifocal and generalized groups, all patients (45%) were evaluated by means of subdural grid and strip electrode recordings, whereas electrophysiological localization in the remaining patients was derived from ictal and interictal scalp recordings. The seizure foci were found to be extratemporal in six patients (55%) and temporal in five patients (45%). Surgical intervention consisted of craniotomy and seizure foci resection guided by electrocorticographic monitoring and functional mapping in five awake (45%) and six asleep (55%) patients. Neuropathological examination of the resected seizure foci revealed cortical tubers in eight patients and diffuse gliosis in three patients. Follow up ranged from 8 to 127 months (mean 35 months). Six patients (55%) were seizure free, half of whom were not receiving antiepileptic drugs (AEDs); three patients (27%) had a greater than 70% reduction in seizure frequency, although they required AEDs; one patient (9%) had a 50% temporary reduction in seizure frequency during the initial 6-month postoperative period; and one patient (9%) was lost to follow-up study. From this small but adequately followed patient population with TS, the authors conclude that cortical resection of seizure foci tailored to electrocorticographic findings and functional mapping is encouraging for this difficult to manage patient population with medically intractable epilepsy.

Neuropathology of the limbic system

The history and development of the fanciful terminology concerning the structures of the limbic system are discussed. The diseases involving the limbic system are divided into three groups; (1) diseases in which the limbic system is more or less selectively involved, such as limbic encephalitis, herpes simplex encephalitis, cerebral confusions by the falx and tentorium, and internal herniations through the falx and tentorium; (2) diseases in which the limbic system is predominantly involved, such as arhinencephalia, holoprosencephaly, cyst of cavum septi pellucidi, Pick's disease, Alzheimer's disease, hippocampal sclerosis, and vascular diseases of the hippocampal formation; and (3) diseases in which the limbic system is randomly involved, such as various types of neoplasms and vascular and inflammatory lesions. The relationship between destructive lesions of the hippocampus and memory also is emphasized.

Referral of Asian patients to a GI clinic

This study compared gastrointestinal (GI) symptoms and psychiatric morbidity in consecutive new out-patients presenting to a district general hospital. In a 6-month period 36 patients of South Asian origin were referred to the clinic. They were compared in terms of GI symptoms and psychiatric morbidity with white European controls, both with a large sample of clinic attenders, and with a subsample of 36 matched for age, gender, and diagnosis. A total of 72% (26 of 36) of Asian patients had functional GI disorders compared to 48% (42 of 88) of white patients (p < 0.05). However, comparisons of matched patients showed that Asian patients with functional GI disorders had less severe GI symptoms than the matched white patients, and fewer had psychiatric disorder (23% of Asians and 42% of white Europeans). These results suggest that the threshold for referral for Asian patients with functional GI disorders to hospital clinics is lower than for white patients. Detection and management of somatization in Asian patients in primary care need to be improved, and referral patterns of general practitioners need to be explored in future research.

Global cerebral dysplasia due to dysplasia and hyperplasia of periventricular germinal cells

Complete obliteration of the cerebral ventricular cavities has not been previously described as an entity among central nervous system malformations. Markedly disorganized maldevelopment of the deep cerebral nuclei and moderately disorganized maldevelopment of the cerebral cortex were observed in the brains of two cases, a 3-year-old female and a male newborn infant. One showed complete and the other partial obliteration of the lateral and third ventricles. Both showed severe maldevelopment of the basal ganglia, which were represented by a large central mass consisting of randomly distributed multiple nodules of gray matter without any discernible differentiation into lenticulostriate nuclei, thalamus, or hypothalamus. Minor malformations involved the cerebral cortex, cerebellum, and mesencephalon to varying degrees. Each of the above two cases was thought to be unique and different until the brain of a fetus of 155 days' gestation was studied. This fetal brain showed exuberant and disorganized periventricular proliferation and migration of germinal matrix cells, with obliteration of the lateral and third ventricles. It was concluded that hyperplasia and disorganized migration of the periventricular germinal matrix early in gestation of whatever cause itself can result in severe maldevelopment of the deep cerebral nuclei and obliteration of the ventricular cavities.

Embarking upon a medical career: psychological morbidity in first year medical students

This study was undertaken to measure the prevalence of psychological morbidity, and the nature and source of stress, in first year medical students. Two hundred and four first year medical students at a university in the north of England were sent a postal, self-report questionnaire. They were asked to complete the General Health Questionnaire (GHQ), the Stress Incident Record and to give details of their alcohol consumption. A total of 172 students (84.3%) replied. Thirty-six per cent of the students scored above the threshold of the GHQ, indicating probable psychological disturbance. There was no difference between men and women. Approximately half of the students described a stressful incident, the majority of which were related to medical training rather than to personal problems. Male students reported drinking significantly more alcohol than female students, but there was no relationship between levels of alcohol consumption and either psychological disturbance or reporting of stress. The findings suggest that even at the preliminary stages of medical training, many students find aspects of the medical course very stressful. The psychological well-being of medical students needs to be more carefully addressed, and closer attention paid to the styles of medical teaching that may provoke avoidable distress.

Radiation therapy for sarcoid of the thalamus/posterior third ventricle: case report

There are a limited number of previously reported cases involving the use of radiation therapy for sarcoid of the brain. The case of a 22-year-old man with a thalamic/posterior third ventricle sarcoid mass that grew despite steroid medication is presented. The patient was treated with external beam radiation to a total dose of 20 Gy, with 2-Gy fractions over 14 elapsed days. A complete radiographic response was achieved 4 months after radiation was completed. Radiographic follow-up through 8 months postradiation shows no evidence of disease recurrence. Fractionated radiation therapy in low-to-moderate doses appears to be efficacious in steroid-refractory sarcoid of the brain.

Grading brain tumors other than astrocytomas

In this article, a critique of the literature is presented concerning the correlation (or lack thereof) between the prognoses of patients with brain tumors other than astrocytomas and the histologic grades of their tumors. In general, the histologic "grade" is a shorthand description of the tumor type and should be understood only as a means of communication of a system of histologic classification and not as implying any indication of biologic behavior, because the "grade" is a relatively poor indicator of the patient's prognosis. Other biological factors (such as the age of the patient, the site of the tumor, and the extent of the surgical resection) are better correlates of subsequent behavior of the neoplasm. The authors suggest (without proof, however) that the determination of potential tumor-doubling times by measuring the percentages of tumor cells in S-phase (by flow cytometry) and in the cell cycle (by immunocytochemistry) may provide a better measure of the degree of malignancy (defined by the rapidity of growth) than can the histologic characteristics by themselves.

Electrocorticography in patients with medically intractable temporal lobe seizures. I. Quantification of epileptiform discharges prior to resective surgery

We studied retrospectively the intraoperative preresection electrocorticograms (ECoGs) of 72 patients undergoing surgery for medically intractable, mostly complex partial, temporal lobe seizures (TLS). Quantification of interictal epileptiform discharges (EDs) detected visually at each electrode location in 2 min recording epochs included computations of ED rates (EDs/min) and cumulative voltages (CuVs) (microV/min). Of 6388 EDs, 81% involved the infratemporal surface, 18% the lateral temporal surface and 1% the orbital frontal area. Forty-eight patients (67%) demonstrated multiple (up to 5 or more), temporally independent foci. Dominant foci in medial and lateral infratemporal locations were about equally common and were significantly more frequent than in lateral temporal locations. Rankings of ED CuVs and rates at individual cortical locations defined 4 areas of "relative interictal cortical epileptogenicity." These were arranged in an orderly pattern with the anterior parahippocampal gyrus and the inferomedial surface of the temporal tip displaying the highest and the lateral temporal and posterior infratemporal cortices showing the lowest propensity to the interictal epileptiform discharge. Individual areas were not characterized by distinct clinical seizure manifestations. Preresection ECoGs provide information on the epileptogenic dysfunction that involves most of the temporal lobe of patients with medically intractable TLS.

Electrocorticography in patients with medically intractable temporal lobe seizures. II. Quantification of epileptiform discharges following successive stages of resective surgery

We quantified retrospectively the interictal epileptiform discharges (EDs) detected visually in the electrocorticograms (ECoGs) of 42 patients undergoing successive stages of anterior temporal lobectomy for medically intractable temporal lobe seizures (TLS). Following first resection sparing the hippocampus (H) and the parahippocampal gyrus (PHG), EDs were recorded on both structures in all patients and by far exceeded in amount those on residual lateral infratemporal and lateral temporal cortices. Frequently, EDs occurred apparently simultaneously but with opposite polarities on the H and the PHG, but more complex relationships were also evident in most individuals. These features likely reflected abnormal post-synaptic activity generated at different locations and cortical depths within the H, PHG, or both. Quantification of epileptiform activity and the effects of selective anterior hippocampectomy or parahippocampectomy suggested that both the H and PHG had remarkable epileptogenic potential. Levels of epileptiform activity were not significantly different in the H and PHG and in the H of subjects with and without H sclerosis. After final resection, including the amygdaloid nucleus (AN), anterior H and PHG, interictal EDs were present, although markedly diminished, in 35 patients. Postresection foci were significantly less numerous and extensive, and attained smaller maximal voltages, than did foci before and after first resection.

Intraventricular fat from a ruptured sacral dermoid cyst: clinical, radiographic, and pathological correlation. Case report

The authors report a unique case of a dermoid cyst that ruptured into the lumbosacral subarachnoid space following trauma, resulting in dissemination of cyst contents into the ventricles and cerebrospinal subarachnoid spaces. An intraspinous source should be considered when intraventricular fat is identified without a clear intracranial source.

Pituitary oncocytomas: clinical features, characteristics in cell culture, and treatment recommendations

To determine whether there are significant differences between oncocytomas and pituitary adenomas, we evaluated clinical features, treatment regimens and outcome in 23 males and 9 females (average age 64 years, range 43-81 years) with the histologic diagnosis of pure pituitary oncocytomas (> 95% oncocytes). Symptom duration was six to twelve months in 6 cases (19%) and more than one year in 19 cases (59%). Three patients presented with sudden onset of symptoms, and were found to have hemorrhage within their tumors. Visual loss (69%) and symptoms of hypopituitarism (44%) were the most common presenting complaints. Preoperative endocrine profiles revealed abnormalities in most cases, including pituitary insufficiency in 56% and hyperprolactinemia in 59%. The tumors were typically large at presentation; all but one had suprasellar extension. 28 patients underwent transsphenoidal tumor resections; 4 underwent subfrontal craniotomies. Gross dural invasion was found at surgery in 11 cases. At a mean followup of 31 months (range 2-68 months), recurrent tumor was identified in 4 patients (12.5%). Tumor size, dural invasion, preoperative endocrine profile, and postoperative radiotherapy did not correlate with recurrence. Among seven oncocytomas grown in culture, five demonstrated two distinct cell types consisting of oncocytes and typical adenoma cells, respectively. Oncocytomas often have a different clinical presentation than functional pituitary adenomas.

Fetal hemoglobin induction with butyric acid: efficacy and toxicity

Butyric acid induces fetal hemoglobin (HbF), a property of potential therapeutic advantage in patients with disorders of globin chain synthesis. We performed dose escalation studies of this compound in baboons to assess whether clinically significant increases in HbF are achievable, and to define the associated toxicities. Additionally, the effect of butyrate in combination with erythropoietin on HbF induction was assessed. HbF induction in response to butyrate was dependent on the dose and duration of treatment. Doses of butyrate less than 4 g/kg/d were associated with minimal toxicity (hypokalemia) and significant HbF induction in these nonanemic animals, with 1 g/kg/d producing an increase in HbF-containing reticulocytes (F reticulocytes) from 0.9% to 8.7% and an increase in HbF from 0.8% to 1.4%. A dose of 2 g/kg/d resulted in an increase in F reticulocytes from 2.1% to 27.8% and an increase in HbF from 0.7% to 2.2%. Doses of 4 g/kg/d in another animal produced an increase in F reticulocytes from 1% to 21.6% and in HbF from 1.9% to 5.3%. Infusions in excess of 4 g/kg/d were complicated (after a variable amount of time) by a decreased level of alertness (caused by hyperosmolality or butyrate itself) and hematologic toxicity (with declines in reticulocyte, white blood cell, and platelet counts). Prolonged infusions of high doses of butyrate (8 to 10 g/kg/d) were associated with peak F reticulocyte percentages reaching 38% to 64.5% and HbF reaching levels in excess of 20%. These high doses (8 to 10 g/kg/d) were complicated in two animals with a striking and unique neuropathologic picture and, in one animal, multiorgan system failure. Erythropoietin in combination with butyrate, induced F reticulocytosis in an additive manner. We conclude that butyric acid is a strong inducer of HbF, particularly when administered in combination with erythropoietin. As chronic toxicities remain undefined, patients in future clinical trials of this and similar compounds should be monitored closely for evidence of neurologic toxicity.

Brain hemorrhages in cocaine-exposed human fetuses

Autopsies of 4 fetuses exposed to maternal cocaine are reported. Brain examination revealed hemorrhages in 3 of the fetuses involving the germinal matrix. The hemorrhages resembled subependymal germinal matrix hemorrhages seen as postnatal complications in premature infants with idiopathic respiratory distress syndrome. One of the placentas had sonographic evidence of abruption which could not be confirmed pathologically. The findings are discussed in light of reports of neurobehavioral deficits and other congenital anomalies in children and animals exposed to cocaine in utero. Speculations about the pathophysiologic events leading to these findings are made.

Correlation of single-mode fiber radiation response and fabrication parameters

Statistically significant correlations have been established between certain fabrication parameters of matched clad, single-mode optical fiber waveguides and their response to an ionizing radiation dose of 2000 rad. The reCOVE:ry data measured at -35 degrees C following exposure have been fit to nth-order kinetic behavior where the adjustable parameters are the initial and permanent incremental losses (A(o) and A(f), respectively), the half-life of attenuation tau, and the order of kinetics n. The set of fibers chosen for analysis had Ge-doped silica cores. In fibers with Ge-F-doped silica clads, A(o) correlates with the concentration of Ge-doped into the fiber core; A(f) correlates with the ratio of oxygen to reagents used during core deposition; and tau and n correlate with a two-way interaction of core oxygen and fiber draw speed. In P-F-doped clad fibers, the P concentration has been found to correlate with the order of the kinetics of recovery.

The effect of age on the latency of radiation myelopathy

The latent period to forelimb paresis following photon irradiation of the cervical spinal cord was evaluated in Sprague-Dawley rats ranging in age from 9 days to adulthood. The radiation was administered dorsally in single fractions, and in 15-day-old animals, to different lengths of the rostral cord and in doses ranging from 16 to 38 Gy. The duration of the latent period was found to be directly proportional to the age of the animal at the time of irradiation, and independent of radiation dose or the volume of the cervical cord which was irradiated. In the majority of paretic animals, the irradiated segment of the spinal cord demonstrated white matter necrosis. The results indicate that in the developing rat, the manifestations of radiation myelopathy are delayed by an interval determined in part by the age of the animal at the time of irradiation.

Comparison of postmortem magnetic resonance imaging and neuropathologic findings in the cerebral white matter

Two types of high-signal intensity abnormalities are frequently found bilaterally in the cerebral white matter of brains of elderly patients on T2-weighted magnetic resonance imaging (MRI) scans. One is located in the immediate periventricular region; the other, in the deep subcortical white matter (centrum semiovale). The diagnostic implications of this second type continue to be uncertain. To determine the neuropathologic correlates of these lesions, the brains from seven elderly patients were fixed in buffered formaldehyde solution, subjected to MRI scanning, and examined neuropathologically. Variable degrees of bilateral periventricular (subependymal) sharply defined areas of high-signal intensity were found in all the brains, and the larger of these showed corresponding areas of myelin pallor with gliosis and dilated perivascular spaces. Discrete bilateral patches of high-signal intensity were found in the centrum semiovale in five patients. Myelin and axon stains showed varying degrees of diffuse white matter pallor in many areas examined, both with and without these areas of high-signal intensity on MRI scans. Neither the myelin nor the axon stains showed discrete white matter abnormalities that corresponded to the MRI findings. We believe that these changes, so commonly found on MRI scans in the elderly, reflect actual changes in the white matter but that their nature and clinical significance need to be elucidated.

Cerebellar venous infarction: case report with clinicopathologic correlation

A diabetic man developed a severe hyperosmolar state resulting in coma. CT of the head showed bilateral cerebellar hemorrhages. Despite medical treatment, he deteriorated and died. At autopsy, the straight sinus was thrombosed. There were bilateral, hemorrhagic, cerebellar venous infarctions. This condition is rare because of abundant collateral venous drainage.

Congenital difficulties with swallowing and breathing associated with maternal polyhydramnios: neurocristopathy or medullary infarction?

Two babies with congenital difficulties in swallowing and breathing are presented and contrasted. Both were associated with maternal polyhydramnios, but one was due to medullary infarction and the other to a malformation ("neurocristopathy"). In the former case, isolated tenth and twelfth cranial nerve palsies provided the clue as to the correct etiology, whereas the latter baby had dyscoordination of swallowing and breathing with sleep apnea ("Ondine's curse"). It is somewhat ironic that the case without a difficult delivery had the infarct, probably prenatal in onset, whereas the one with a difficult delivery had the congenital malformation. Neural crest cells are known to migrate widely and to develop greatly different functions, but the fact that their central associations of neural tube origin may also be affected has not previously been emphasized in the etiopathogenesis of the congenital malformation. A variety of syndromes with combinations of many defects may be seen in which too many or too few cells are formed, with more or less serious consequences especially for the respiratory and gastrointestinal systems.

Transsynaptic spread of varicella zoster virus through the visual system: a mechanism of viral dissemination in the central nervous system

We report a patient with pathologic evidence of anterograde spread of varicella zoster virus (VZV) through the visual system. A 29-year-old homosexual man developed the acquired immunodeficiency syndrome (AIDS) 2 months before the onset of left herpes zoster ophthalmicus. During the next 11 months, the zoster infection progressed to involve the left eye, with resultant keratitis, iritis, retinitis, and eventual blindness. Later, the patient developed bilateral blindness, left hemiparesis, and fatal pneumonia. At autopsy, the brain revealed destruction of the visual system and adjacent structures, with sparing of the remainder of the brain. Glial cells near the areas of necrosis showed Cowdry type A intranuclear inclusions. In situ hybridization with probes to VZV nucleic acid sequences were positive in the necrotic brain and retinal areas. Hybridization with probes to cytomegalovirus, herpes simplex virus type II, human immunodeficiency virus, and Epstein-Barr virus were negative. Electron microscopy revealed characteristic herpes group nucleocapsids. This case provides insight into the mechanisms of virus dissemination and the production of encephalitis.

Choroid plexus cysts in fetuses with trisomy 18

An association between fetal choroid plexus cysts and trisomy 18 has been suggested. However, the prevalence of such cysts in aneuploid fetuses is unknown. To determine this frequency, we studied 14 fetuses with trisomy 18 examined at the Central Laboratory for Human Embryology. Five fetuses were found to have choroid plexus cysts on postmortem ultrasound examination. All those with cysts were earlier than 26 weeks in gestation, and the prevalence among second-trimester fetuses was 71.4%. In contrast, such cysts are reported in less than 1% of the general population of second-trimester fetuses. Thus, choroid plexus cysts are common in trisomy 18, and the finding of such cysts on a second-trimester ultrasound examination should suggest further evaluation, including chromosome analysis.