Safety outcomes of pembrolizumab with platinum agent chemotherapy combined with 5-fluorouracil or taxane derivative in head and neck cancer

INTRODUCTION

For patients with metastatic head and neck squamous cell cancer (HNSCC), the outcomes of pembrolizumab in combination with a platinum agent and taxane as first-line therapy remain unknown. The purpose of this study is to characterize the impact of substituting the 5-fluorouracil (5-FU) backbone for a taxane in this chemoimmunotherapy regimen on safety/tolerability and survival outcomes.

METHODS

This was an IRB-approved, single-center, retrospective, active comparator, new-user design study in adult patients with HNSCC treated between January 2018 and September 2021. The primary objective was to assess safety and tolerability of pembrolizumab in combination with a platinum agent and taxane against an active comparator arm of pembrolizumab in combination with a platinum agent and 5-FU. Safety and tolerability were evaluated by assessing differences in overall toxicities, with further secondary analysis evaluating differences in hematologic toxicities and pre-defined non-hematologic toxicities.

RESULTS

There was no statistical difference demonstrated with the primary endpoint between the cohorts. Reduced toxicity rates were found in the taxane arm for mucositis and creatinine levels. No grade 4 non-hematologic toxicities were reported. Patients receiving 5-FU were more likely to have dose reductions upfront, discontinue treatment due to intolerances and had significantly higher mucositis.

CONCLUSIONS

This study helps to characterize the safety profile and activity of pembrolizumab in combination with a platinum agent and taxane derivative in HNSCC patients. Within our study, substitution of 5-FU with a taxane did not show an increased risk of toxicities, worsened survival, or decreased odds of achieving a response. Mucositis and elevated creatinine rates were significantly reduced within the taxane arm.

Validation of a Genomic Classifier in the NRG Oncology/RTOG 0521 Phase III Trial of Docetaxel with Androgen Suppression and Radiotherapy for Localized High-Risk Prostate Cancer

PURPOSE/OBJECTIVE(S)

Decipher is a prognostic genomic classifier (GC) validated in several prospective NRG Oncology Phase III trials. Herein, we validate the GC in pre-treatment biopsy samples for risk stratification in a cohort of high-risk men treated with definitive radiotherapy and androgen suppression with or without docetaxel chemotherapy.

MATERIALS/METHODS

As per a pre-specified and approved NCI analysis plan (Navigator #1061), we obtained available formalin-fixed paraffin-embedded tissue from biopsy specimens from the NRG biobank from patients enrolled on the NRG/RTOG 0521 randomized phase III trial. After central review, the highest-grade tumors were profiled on clinical-grade whole-transcriptome arrays (Veracyte, San Diego, CA) and GC scores were obtained. Pre-specified categorical GC scores, adjusted for archival tissue analysis, were used to define higher (>0.46) and lower (≤0.46) risk groups. The primary objective was to validate the independent prognostic ability of GC for metastasis-free survival (MFS) with Cox multivariable analyses (MVA).

RESULTS

Samples were obtained from 283 consented, evaluable patients with tissue (50% of trial) yielding 183 (65%) GC scores that passed quality metrics, 91 from control and 92 from the interventional arm. Median age was 66 years, median PSA was 19.3 ng/uL (IQR: 8.1-41.4), 81% had clinical stage ≥T2 and 80% had Gleason score ≥8 (47% ≥9). Median GC score was 0.55 (IQR: 0.38-0.78) and overall the arms were balanced for key covariates. With a median follow-up of 9.9 years (IQR: 9.3, 10.7), 67 MFS events including 34 distant metastases (DM) were observed. On MVA, only the GC (per 0.1 unit) was independently associated with MFS (HR 1.12, 95% CI 1.01-1.25) as well as DM (sHR 1.22, 95% CI 1.06-1.41), whereas the 4 pre-defined trial risk groups used for stratification (based on Gleason score, T-stage and PSA), randomization and patient age were not. For categorical GC, on MVA, higher-risk GC patients (65%) had worse DM (sHR 2.82, 95% CI 1.1-7.3) compared to those with lower GC. Cumulative incidence of DM at 10-years was 27% for higher GC vs 9% (95% CI 7-18%) for lower GC. No biomarker-by-treatment interaction with GC and the addition of docetaxel was detected.

CONCLUSION

In pre-treatment biopsy samples from a randomized Phase 3 trial cohort, GC demonstrated its ability to further risk stratify clinically high-risk men demonstrating an independent association of GC score with DM and MFS. High-risk prostate cancer is a heterogeneous disease state and GC can improve risk stratification to help personalize shared decision-making. NRG-GU009/PREDICT-RT (NCT04513717) aims to determine the optimal therapy based on GC score for high-risk prostate cancer.

Long-Term Follow-Up Analysis of NRG Oncology RTOG 0415: A Randomized Phase III Non-Inferiority Study Comparing Two Fractionation Schedules in Patients with Favorable-Risk Prostate Cancer

PURPOSE/OBJECTIVE(S)

To assess whether the efficacy of a hypofractionated (H) schedule is no worse than a conventional (C) schedule in men with low-risk prostate cancer.

MATERIALS/METHODS

Accrual began April 2006 and ended in December 2009. 1115 men with favorable-risk prostate cancer were randomly assigned 1:1 to a conventional (C) schedule (73.8 Gy in 41 fractions over 8.2 weeks) or to a hypofractionated (H) schedule (70 Gy in 28 fractions over 5.6 weeks). The trial was designed to establish with 90% power and alpha = 0.05 that (H) results in 5-year disease-free survival (DFS) that is not lower than (C) by more than 7% (hazard ratio (HR) < 1.52). Protocol specified secondary endpoints evaluated for noninferiority include: biochemical recurrence (BR), local progression, disease-specific survival, and overall survival.

RESULTS

One thousand ninety-two protocol eligible men were analyzed: 542 to C and 550 to H. Median follow-up is 12.75 years. Baseline characteristics were not different according to treatment arm. The estimated 12-year DFS is 56.1% (95% CI 51.5, 60.5) in the C arm and 61.8% (57.2, 66.0) in the H arm. The DFS hazard ratio (H/C) is 0.85 (0.71-1.03), confirming non-inferiority (p<0.001). Twelve-year cumulative incidence of biochemical recurrence (BR) was 17.0% (CI 13.8, 20.5) in the C-RT and 9.9% (CI 7.5, 12.6) in the H-RT arm; (HR = 0.56, (0.40-0.78) suggesting improved efficacy with H. Additional pre-specified secondary endpoints were non-inferior Late Grade ≥ 3 GI toxicity is 3.2% (C) vs. 4.4% (H), Relative risk (RR) for H vs. C 1.39 (CI 0.75, 2.55) Late Grade ≥ 3 GU toxicity is 3.4% (C) vs. 4.2% (H), RR = 1.26 (CI 0.69, 2.30).

CONCLUSION

In men with favorable-risk prostate cancer, long-term disease-free survival is non-inferior with 70 Gy in 28 fractions compared to 73.8 Gy in 41 fractions. The risk of BR is reduced with moderate hypofractionation. No differences in late Grade ≥3 GI/GU toxicity were observed between the arms. (ClinicalTrials.gov identifier: NCT00331773).

841 The psychological impact of Foundation Interim Year 1 Placements on Final Year UK Medical Students Transitioning to Foundation Year One During the COVID Era

Introduction

During the COVID pandemic, the 2019-2020 cohort of final year students were invited to participate in Foundation interim Year 1 placements (FiY1). FiY1 aimed to ease transition to Foundation Year 1 doctor (FY1). We assessed the psychological impact of FiY1 on final year medical students.

Method

A cross-sectional survey was distributed to final year medical students in the UK between June 4th and July 4th, 2020. The survey contained the following domains: participant demographics, rationale for FiY1 participation, a checklist of the key safety principles for FiY1s, the Hospital Anxiety and Depression Scale and the Perceived Stress scale-4.

Results

107 final years responded to the survey. 72.0% (n = 77) of final year students surveyed were working as FiY1s. Final year students participating in FiY1 postings had reduced rates of anxiety (29.9% vs 43.4%, P = 0.186), depression (5.2% vs 20.0%, P = 0.018) and lower perceived stress levels (5.0 vs 7.2, P &lt; 0.001). 19.5% (15/77) FiY1s reported working beyond their competency, 27.3% (22/77) felt unsupervised, but 94.8% (73/77) of FiY1s felt the post prepared them for FY1.

Conclusions

Students participating in FiY1 postings felt less stressed and depressed than those not participating in the scheme and the majority felt it was preparing them for FY1.

Immune checkpoint inhibitors in gastrointestinal malignancies: what can we learn from experience with other tumors?

Gastrointestinal (GI) malignancies are some of the most common cancers worldwide with high rates of morbidity and mortality. Immune checkpoint inhibitors have afforded additional treatment options for patients, but their success has been limited. Conversely, in other tumor types such as lung cancer, melanoma and renal cell carcinoma, treatment strategies with immune checkpoint inhibitors have propelled those agents into the front lines of treatment. Strategies utilized include combining immune checkpoint inhibitors with chemotherapy, other checkpoint inhibitors, and targeted therapy. In this review, we analyze combination strategies employed in other tumor types to help identify current and future approaches toward improving outcomes with immunotherapy in GI malignancies.

13C NMR spectroscopy of heterocycles: 1-phenyl-3-aryl/t-butyl-5-arylpyrazoles

A series of chalcones 1–12 were converted to pyrazolines (1Pi–12Pi) by reaction with phenylhydrazine followed by DDQ oxidation to produce the corresponding pyrazoles (1Pz–12Pz). Three 1-phenyl-3-t-butyl-5-arylpyrazoles (13Pz–15Pz) were synthesized using an analogous approach. Molecular modeling studies predicted the 5-aryl group of the pyrazoles for both series to have a torsion angle of 52°–54° whereas the 1-phenyl group was predicted to have 35°–37° torsion angles. The 3-aryl group was predicted to be essentially coplanar (−3°) with the pyrazole system in the first series. 13C NMR data for both series, 1Pz–12Pz and 13Pz–15Pz, were collected in DMSO-d6 at 50°C. A plot of the C4 chemical shifts for 1Pz–12Pz versus Hammet constants for 5-aryl substituents yielded a very good linear correlation (R2=0.96) with a slope of 1.5. The chemical shift data for C4 showed little or no dependence on 3-aryl substituents. The result for 13Pz–15Pz, despite only three points, was consistent with the first series results and yielded a ρ value of 2.0. Distal transmission of substituent effects (5-aryl groups) to C4 of the pyrazole system was reduced by roughly 50–60% of that of the analogous planar isoxazole system, but are not consistent with results for the similarly twisted 4-bromoisoxazoles.

Balancing efficacy and bleeding risk in the prevention of stroke due to atrial fibrillation with newer oral anticoagulants

With the evaluation and approval of newer oral anticoagulants such as the factor IIa inhibitor, dabigatran etexilate and the factor Xa inhibitors, rivaroxaban and apixaban, strategies for stroke prevention in atrial fibrillation need a thorough re-evaluation of current options. Clinicians are naturally excited about the imminent introduction of these newer drugs that do not need international normalized ratio (INR) monitoring, besides having no drug-food and minimal drug-drug interactions. However, as with all new drugs, it is always prudent to use these judiciously so that they stay in our therapeutic armamentarium for a long time. More than 56 years after the introduction of warfarin we now have three drugs, viz., dabigatran 150 mg bid, rivaroxaban 20 mg od, and apixaban 5 mg bid which were effective in comparison with warfarin in reducing the risk of stroke and bleeding in the landmark trials, RE-LY, ROCKET-AF, and ARISTOTLE respectively. There is a thin dividing line between physiological hemostasis and pathological thrombosis. Routine INR monitoring may not be required but in special situations, such as prior to major surgery, overdose, non-compliance or stroke while on the anticoagulant, one may wish to know whether there are any laboratory measures of efficacy or means of reversal of over anticoagulation. Similar questions may be raised about other situations such as renal dysfunction, cardioversion, ablation procedures, post-stenting, or switch to and from warfarin, heparin or LMWH? This document is an attempt to address these concerns based on available evidence and give physicians a perspective and practice guidelines on how best to use these agents, both old and new, for optimal patient outcomes, maximizing efficacy and minimizing risk.

Thrombotic microangiopathy as a complication of recurrent pancreatitis

Acute pancreatitis as a cause of thrombotic microangiopathy is very rare. We report a case of 40-year-old woman with idiopathic recurrent pancreatitis, who presented with acute pancreatitis complicated by thrombotic microangiopathy. Although thrombotic thrombocytopenic purpura/hemolytic uremic syndrome (TTP/HUS) has been reported as causing acute pancreatitis, the induction of TTP/HUS by pancreatitis is rare. As far as we are aware this is the first reported case of TTP/HUS in association with pancreatitis in India. Our patient had a complete recovery of her thrombotic microangiopathy following plasma exchange therapy.

Effective use of polymyxin B hemoperfusion in septic shock complicated by urosepsis

Direct hemoperfusion using polymyxin B–immobilized fiber (PMX-DHP) is an established treatment method for septic shock caused by Gram-negative infections. Here we report one instance in which PMX-DHP therapy has been used successfully in a patient with septic shock from urosepsis. After antibiotic therapy, direct hemoperfusion using polymyxin B helped in cardiovascular stability. The patient recovered from the shock within a few days after treatment with polymyxin-B hemoperfusion. As far as we are aware, this is the first reported case of effective treatment of urosepsis complicated by septic shock using PMX-DHP therapy in India.

DNA Sensing using Nano-crystalline Surface Enhanced Al(2)O(3) Nanopore Sensors

A new solid-state, Al(2)O(3) nanopore sensor with enhanced surface properties for the real-time detection and analysis of individual DNA molecules is reported. Nanopore formation using electron beam based decomposition transformed the local nanostructure and morphology of the pore from an amorphous, stoichiometric structure (O to Al ratio of 1.5) to a hetero-phase crystalline network, deficient in O (O to Al ratio of ~0.6). Direct metallization of the pore region was observed during irradiation, thereby permitting the potential fabrication of nano-scale metallic contacts in the pore region with potential application to nanopore-based DNA sequencing. Dose dependent phase transformations to purely γ and/or α-phase nanocrystallites were also observed during pore formation allowing for surface charge engineering at the nanopore/fluid interface. DNA transport studies revealed an order of magnitude reduction in translocation velocities relative to alternate solid-state architectures, accredited to high surface charge density and the nucleation of charged nanocrystalline domains. The unique surface properties of Al(2)O(3) nanopore sensors makes them ideal for the detection and analysis of ssDNA, dsDNA, RNA secondary structures and small proteins. These nano-scale sensors may also serve as a useful tool in studying the mechanisms driving biological processes including DNA-protein interactions and enzyme activity at the single molecule level.

Meningiomas: report of a hospital-based registry

This is a hospital-based epidemiologic study of meningiomas. Of 1321 central nervous system tumours, meningiomas constituted 21% of the cases, being the second largest category of a single histologic type after astrocytomas. Of the 267 meningiomas studied, 247 were intra-cranial (92.5%). The age of the patients varied between 6 to 84 years. Histological subclassification is presented and treatment schedules discussed. 261 (98%) meningiomas were histologically benign and 5 were malignant meningiomas (1.9%). A 5-year follow-up was available in most cases, with the help of which it was possible to understand the biological behaviour of various sub-types and the influence of other parameters such as location and treatment schedules. Of note was the fact, that out of 261 patients with benign meningiomas, 11 succumbed in the immediate post-operative period and in 8 of these cases, the tumour was located at the base of the skull.

Utilization of oral hypoglycemic agents in a drug-insured U.S. population

OBJECTIVE

Clinical trials provide information regarding the safety and efficacy of medications used to manage type 2 diabetes but do not elucidate drug effectiveness in a typical managed care environment. The aim of this study was to characterize "real-world" drug utilization patterns from both a prescriber and a patient perspective.

RESEARCH DESIGN AND METHODS

We conducted a retrospective analysis of a large administrative pharmacy claims database, using data on continuously pharmacy benefit-eligible members prescribed oral hypoglycemic agents (OHAs).

RESULTS

The 12-month persistence rate for the OHA cohort was low, ranging from 31% for alpha-glucosidase inhibitors to 60% for metformin; compliance rates varied between 70 and 80%. During the first 12 months of therapy, 36% of the patients remaining on therapy at 12 months had one or more therapy modifications. The mean number of therapy changes increased with the length of patient follow-up, with more than half of all patients experiencing at least one therapy change over the duration of follow-up.

CONCLUSIONS

These findings document the wide variation in utilization patterns associated with pharmacological management of type 2 diabetes, suggesting that opportunity exists to optimize its pharmacological management.

Elastase controls the binding of the vitamin D-binding protein (Gc-globulin) to neutrophils: a potential role in the regulation of C5a co-chemotactic activity

The vitamin D-binding protein (DBP) binds to the plasma membranes of numerous cell types and mediates a diverse array of cellular functions. DBP bound to the surface of leukocytes serves as a co-chemotactic factor for C5a, significantly enhancing the chemotactic activity of pM concentrations of C5a. This study investigated the regulation of DBP binding to neutrophils as a possible key step in the process of chemotaxis enhancement to C5a. Using radioiodinated DBP as a probe, neutrophils released 70% of previously bound DBP into the extracellular media during a 60-min incubation at 37 degrees C. This was suppressed by serine protease inhibitors (PMSF, Pefabloc SC), but not by metallo- or thiol-protease inhibitors. DBP shed from neutrophils had no detectable alteration in its m.w., suggesting that a serine protease probably cleaves the DBP binding site, releasing DBP in an unaltered form. Cells treated with PMSF accumulate DBP vs time with over 90% of the protein localized to the plasma membrane. Purified neutrophil plasma membranes were used to screen a panel of protease inhibitors for their ability to suppress shedding of the DBP binding site. Only inhibitors to neutrophil elastase prevented the loss of membrane DBP-binding capacity. Moreover, treatment of intact neutrophils with elastase inhibitors prevented the generation of C5a co-chemotactic activity from DBP. These results indicate that steady state binding of DBP is essential for co-chemotactic activity, and further suggest that neutrophil elastase may play a critical role in the C5a co-chemotactic mechanism.

Traumatic diaphragmatic rupture: associated injuries and outcome

A retrospective case note analysis was performed on all patients treated for traumatic diaphragmatic rupture (TDR) at a major teaching hospital between January 1990 and August 1998. Patients were identified from the prospectively maintained UK Trauma and Research Network Database. Of the 480 cases of torso trauma admitted during the study period, 16 (3.3%) had TDR. Blunt trauma accounted for 13 (81%) of the injuries. A radiological pre-operative diagnosis was made in 10 (62.5%) patients. Seven of these were made on initial chest radiography, two on ultrasound scan and one on computed tomography. All patients underwent a midline laparotomy and TDR was subsequently diagnosed at operation in 6 patients. The left hemidiaphragm was ruptured in 14 (87.5%) patients and there was visceral herniation in 8 (50%). Twelve patients with blunt trauma had associated abdominal and extra-abdominal injuries, but only one of the three patients with penetrating trauma had other injuries. The median Injury Severity Score (range) was 21 (9-50). The median time (range) spent on the intensive care unit was 2 days (0-35 days). Pulmonary complications occurred in 7 (44%) patients. Two (12.5%) patients died from associated head injuries. TDR results from blunt and penetrating torso trauma, is uncommon, rarely occurs in isolation and is associated with a high morbidity and mortality. A high index of suspicion makes early diagnosis more likely as initial physical and radiological signs may be lacking.

Cutaneous and subcutaneous Ewing's sarcoma: an indolent disease

PURPOSE

The occurrence of extraosseous Ewing's sarcoma (ES) in deep soft tissues has been well described, but cases in which this tumor occurs in a primary cutaneous or subcutaneous site have rarely been reported. The superficial variant may be less aggressive than are the more common bony and deep soft tissue counterparts with an apparently favorable outcome. A retrospective review of patients with cutaneous or subcutaneous ES was conducted to analyze outcome and patterns of failure.

METHODS AND MATERIALS

Between July 1985 and March 1997, 14 patients with cutaneous or subcutaneous ES were treated at St. Jude Children's Research Hospital. The median age at presentation was 16 years (range 7-21 years). Anatomic locations included trunk and pelvis (7), upper or lower extremity (4), and head and neck (3). The median size of the lesion was 3 cm (range, 1-12 cm). Thirteen had definitive surgical resections, and one had biopsy of the mass at the time of referral. They were enrolled on institutional (12) or cooperative group (2) protocols. All patients received chemotherapy, composed of vincristine, doxorubicin, cyclophosphamide, ifosfamide, etoposide, and dactinomycin. Patients on institutional protocols received radiation (36 Gy) to the operative bed (150-180 cGy/fraction/day). Postoperative radiotherapy was omitted for 2 patients who had complete resection on the cooperative group study.

RESULTS

No patients had metastatic disease at presentation. Thirteen patients had wide local excision of the primary tumors prior to enrollment on chemotherapy; surgical margins were negative (10), microscopically positive (2), and indeterminate (1). Eleven patients received radiotherapy to the tumor bed; 2 with clear surgical margins were treated without irradiation. The patient who had biopsy only received induction chemotherapy followed by definitive surgical resection and postoperative radiotherapy. The median follow-up was 77 months (range 17-111 months). None of the patients has developed local recurrence or distant metastasis. Several of the patients developed treatment-related sequelae, including veno-occlusive disease of the lung and hemorrhagic cystitis (1), myelodysplastic syndrome (1), chemotherapy-induced ovarian failure (1), moist desquamation (1), and dermatofibroma within the radiotherapy volumes (1).

CONCLUSIONS

Cutaneous and subcutaneous ES are associated with an indolent course and a favorable prognosis when treated with combined modality therapy. Elimination of radiation therapy following complete resection has been tested in the POG 9354 trial. The high rate of local control, low rate of metastatic disease, and excellent overall outcome may suggest a role for less intensive chemotherapy, as well as tailoring to diminish or avoid radiation therapy in completely resected cases, with a goal to minimize toxicity while maintaining a high cure rate.

Long-term follow-up of patients treated with primary radiotherapy for supradiaphragmatic Hodgkin's disease at St. Jude Children's Research Hospital

OBJECTIVE

To assess disease control, patterns of relapse, factors predictive of relapse, and late effects of treatment, we reviewed all cases of supradiaphragmatic (SD) Hodgkin's disease (HD) treated with primary radiation therapy (RT) at our institution.

METHODS

We retrospectively reviewed the disease characteristics, treatment history, and long-term outcome of the 106 patients with Stage I and II supradiaphragmatic HD who received definitive irradiation at St. Jude Children's Research Hospital between 1970 and 1995. As of the date of analysis, 95 patients are alive, with a median follow-up of 13.3 years (range, 1.9-24.2 years).

RESULTS

The median age at diagnosis was 14.7 years (range, 3.7-22.7). Involved-field RT was given to 13 patients (12%), whereas 37 (35%) had mantle RT, 51 patients (48%) had subtotal nodal irradiation, and 5 (5%) had total nodal irradiation. Relapsed disease developed in 26 patients at a median of 1.8 years (range, 0.2-9.3 years). The 5- and 10-year estimated cumulative incidences of relapse were 20.9% +/- 4.0% and 25.1% +/- 4.3%, respectively. With a median dose of 36 Gy (range, 32-40), in-field failure rate was 6.2%, whereas subdiaphragmatic relapse in sites irradiated prophylactically was 1.5%. There was a trend toward an increased incidence of relapse with higher ESR (p = 0.088) and greater number of sites of disease (p = 0.087). Age, stage, histology, nodal disease > or = 6 cm, the presence of bulky mediastinal disease, and the method of staging did not affect the incidence of relapse. The pattern of failure could not be predicted based on the stage of disease, the extent of subdiaphragmatic staging, the extent of radiation therapy, or the sequence of RT fields-"ping pong" vs. sequential. Subset analysis of Stage II patients revealed significantly more relapses in clinically staged patients. Excluding Stage IA patients with high cervical disease or peripheral nodal disease, nodal extension failures were more common for patients undergoing limited-volume RT, whereas extranodal relapses were likely after STNI or TNI. The estimated 10- and 15-year cumulative incidences of second malignancies were 2.9% +/- 1.6% and 7.9% +/- 3.3%, respectively. Our patients are at increased risk of second malignancies (11-fold), and fatal cardiac (68-fold) and infectious (33-fold) complications. Overall survival at 10 years was 90.8% +/- 3.2%; event-free survival was 72.1% +/- 5.0%.

CONCLUSIONS

The current analysis confirms the curative potential of RT for HD in children and adolescents. Despite successful salvage therapy, relapsed disease remained the principal cause of death in our cohort. Excess risk of septic death in asplenic patients, fatal heart disease, and second malignancies may further compromise the ultimate cure of HD in long-term survivors.

Pediatric choroid plexus neoplasms

PURPOSE

Choroid plexus tumors (CPT) are rare childhood neoplasms. The relatively small number of reported cases and the controversies surrounding the clinical and pathological classification of these tumors have made it difficult to define a standard of care for these patients. Our intention is to contribute to the body of knowledge of these tumors and further define the role of adjuvant therapy.

METHODS AND MATERIALS

We performed a retrospective review of 14 children with choroid plexus neoplasms referred to St. Jude Children's Research Hospital between October 1985 and December 1987. Ten patients had choroid plexus carcinoma (CPC) based on pathologic criteria and evidence of brain invasion at surgery or leptomeningeal disease (M+); 4 patients had choroid plexus papilloma (CPP). Patients with CPP were initially treated with surgery alone whereas patients with CPC were generally treated with postoperative therapy that included chemotherapy (CT) and/or craniospinal irradiation (CSI) with a focal boost to the primary site. For most patients CT consisted of combinations of cyclophosphamide, etoposide, vincristine, and a platinum agent. The median CSI dose was 35.2 Gy (range 24-46.2 Gy). The median primary site dose was 55.2 Gy (range 49.6-64 Gy).

RESULTS

Seven of the 10 CPC cases presented with leptomeningeal dissemination; two of these patients have succumbed to disease. Of the 3 patients with M0 status, all are alive with no evidence of disease (NED). The medial time to relapse from the time of surgery was 5.3 mo (range 3-25 mo). Seven CPC patients were treated with gross total resection (GTR). Three of these patients (2 M0, 1 M+) received CT without CSI and are currently NED (27, 69, and 60 mo respectively). One M+ patient progressed on CT and has stable disease after CSI (6 mo), one (M0) received CT and CSI and is NED (120 mo), one (M+) is currently on CT with objective response (3 mo) and one (M+) died of progressive disease (24.5 mo) despite CT and CSI. Three patients with CPC had subtotal resection (STR). One of these patients (M+) received CT and CSI and is NED (23 mo), one (M0) had an elective second resection GTR alone and is currently NED (153 mo), and one (M+) developed progressive disease (13.5 mo) while on CT and died despite CSI. Among the 4 CPP patients, GTR was performed in two; both were NED at 54 and 81 mo. Two patients with CPP (one with focal atypia) were treated with STR initially; both transformed to CPC at 7 and 27 mo, respectively. Both were currently NED following salvage with (1) GTR and CSI alone (98 mo) or (2) STR, CT, and CSI (62 mo). Six of the 12 survivors in this series had significant neuropsychological sequelae.

CONCLUSION

The prognosis of CPP is good for patients treated with GTR. Malignant transformation occurred in 2 CPP patients with less than GTR. Patients with localized CPC who undergo GTR have had a favorable outcome with the addition of chemotherapy or irradiation. CSI may not be routinely indicated in M0 children following GTR. There is evidence that salvage with radiation therapy may be successful following progression on chemotherapy. For patients treated with STR, the use of CT and CSI appears to be necessary.

Squash preparation and frozen section in intraoperative diagnosis of central nervous system tumors

OBJECTIVE

To investigate the diagnostic accuracy of squash preparation (smears) and frozen section (FS) in the rapid intraoperative diagnosis of central nervous system (CNS) tumors.

STUDY DESIGN

One hundred eighty-three CNS tumors were examined over a period of 18 months (January 1995-June 1996). All these were open biopsies, and the smear interpretation was compared with FS findings and paraffin section diagnosis.

RESULTS

In 183 tumors, squash preparation was satisfactory in 156 cases (85.2%), and the diagnostic accuracy was 89.7% (140/156). The accuracy of FS diagnosis was 90.4% (141/156).

CONCLUSION

The squash smear preparation is a fairly accurate and reliable tool in the rapid intraoperative diagnosis of CNS tumors. The accuracy of this technique is nearly as good as that of FS (P value = .9877). With the advent of stereotactic biopsies, the pathologist may have to depend entirely upon cytologic features for a definitive diagnosis.

Identification and analysis of mutations in the Wilson disease gene (ATP7B): population frequencies, genotype-phenotype correlation, and functional analyses

Wilson disease (WD) is an autosomal recessive disorder characterized by toxic accumulation of copper in the liver and subsequently in the brain and other organs. On the basis of sequence homology to known genes, the WD gene (ATP7B) appears to be a copper-transporting P-type ATPase. A search for ATP7B mutations in WD patients from five population samples, including 109 North American patients, revealed 27 distinct mutations, 18 of which are novel. A composite of published findings shows missense mutations in all exons-except in exons 1-5, which encode the six copper-binding motifs, and in exon 21, which spans the carboxy-terminus and the poly(A) tail. Over one-half of all WD mutations occur only rarely in any population sample. A splice-site mutation in exon 12 accounts for 3% of the WD mutations in our sample and produces an in-frame, 39-bp insertion in mRNA of patients homozygous, but not heterozygous, for the mutation. The most common WD mutation (His1069Glu) was represented in approximately 38% of all the WD chromosomes from the North American, Russian, and Swedish samples. In several population cohorts, this mutation deviated from Hardy-Weinberg equilibrium, with an overrepresentation of homozygotes. We did not find a significant correlation between His1069Glu homozygosity and several clinical indices, including age of onset, clinical manifestation, ceruloplasmin activity, hepatic copper levels, and the presence of Kayser-Fleischer rings. Finally, lymphoblast cell lines from individuals homozygous for His1069Glu and 4 other mutations all demonstrated significantly decreased copper-stimulated ATPase activity.

Patterns of failure following bone marrow transplantation for metastatic breast cancer: the role of consolidative local therapy

PURPOSE

The purpose of this analysis is to evaluate the patterns of failure and the role of local therapy in conjunction with bone marrow transplantation (BMT) for metastatic or recurrent breast cancer.

METHODS AND MATERIALS

Between June 1986 and November 1991, 46 patients with hormone unresponsive metastatic or recurrent breast cancer underwent high dose chemotherapy (HDC) with hematopoietic stem cell support. The most commonly used preparative regimen consisted of thiotepa (750 mg/m2), cisplatin (150 mg/m2), and cyclophosphamide (120 mg/kg) followed by autologous BMT. Consolidative surgery or irradiation was considered in patients whose cancer responded to BMT and had localized sites of disease.

RESULTS

Six patients (13%) died of BMT-related complications. Of the remaining 40 patients, 22 were candidates for consolidative therapy, and 18 of those patients received consolidative irradiation (17 patients) or surgery (1 patient) to one or more sites. At median follow-up of 27 months (range, 20-78), 12 of 18 (67%) patients have continuous local control at the 22 consolidated sites (1 of 4 controlled at chest wall sites, 7 of 8 at regional nodal sites, 7 of 7 at localized bone sites, and 1 of 3 at lung/mediastinal sites). Toxicity of consolidative irradiation was mainly limited to myelosuppression in 6 of 17 patients. Two patients did not complete the consolidative local therapy, one because of hematologic toxicity and one because of rapid systemic tumor progression during treatment.

CONCLUSION

In patients with localized areas of extravisceral metastases, consolidative irradiation is feasible with acceptable hematologic toxicity. Consolidative irradiation can result in continuous local control, especially in isolated bone metastases and in regional nodal sites; however, the advantage is less clear in patients undergoing consolidative irradiation for chest wall failures. Because distant visceral metastases still remain a major site of failure after this HDC regimen, a more effective systemic therapy is needed. Consolidative local treatment should be considered in future HDC/BMT protocols for metastatic breast cancer, especially in localized nodal and osseous sites.

Magnetic microcapsules as novel biomonitors of cross-linking agents and diet-dependent reactive oxygen species in the human gastrointestinal tract

Six healthy, scientifically informed human volunteers were given 14C-labeled polyethyleneimine (PEI) microcapsules by mouth. Fecal 14C recovery was inversely related to mean gut transit time (r = -0.66), and the extent of cross-linking between the membrane and core PEI was inversely related to total fecal output (r = -0.81). Cross-linking of PEI microcapsules may be a biomonitor of endogenous cross-linking agents within the human gastrointestinal tract. Extensive loss of [14C]CH3 label occurred from the microcapsules during human transit and in in vitro fermentations with human fecal flora. A mechanism whereby reactive oxygen species could arise in the iron-rich core of these microcapsules, leading to loss of [14C]CH3 label, is proposed.

Diagnosis and treatment of Clostridium difficile colitis

Pseudomembranous colitis associated with antibiotic therapy is almost always due to an overgrowth of Clostridium difficile. If untreated, pseudomembranous colitis can lead to severe diarrhea, hypovolemic shock, toxic dilatation of the colon, cecal perforation, hemorrhage, and death. However, C difficile-associated colitis can mimic the more common "benign" antibiotic-associated diarrhea that is not caused by C difficile. An algorithm for diagnosis management of hospitalized patients with antibiotic diarrhea and C difficile colitis is presented in this review. Diagnosis depends on sigmoidoscopy and/or stool tests for C difficile toxins in all patients with antibiotic-associated diarrhea. If the results of these tests are positive, either metronidazole or vancomycin is recommended for treatment of mild illness, and vancomycin is recommended for treatment of severe illness. Oral therapy is always preferred because it is more reliable. In patients with recurrent or relapsing colitis, treatment with either metronidazole or vancomycin is effective for that episode, but novel approaches, such as the oral or rectal introduction of competing nonpathogenic organisms, may prove to be more successful in prevention of relapses.

The microstructure of cortical neuropil before and after decompression in experimental infantile hydrocephalus

Hydrocephalus is a common clinical disorder and responsible for many pediatric neurological deficits. Relatively little is known about the cellular mechanisms of this disorder and less is known about reconstitution of connectivity following ventricular shunt procedures. In the present studies experimental infantile hydrocephalus produced by kaolin injection was studied in a neonate kitten model. The neuropil of the cerebral cortex was examined in hydrocephalic animals and animals which received a ventriculoperitoneal shunt to reduce ventriculomegaly. The brains were processed for Golgi silver impregnation and electron microscopy to study the detailed dendritic and synaptic architecture. The periventricular region of the hydrocephalic animals exhibited increased extracellular space and signs of neuronal degeneration. Components of the deep neuropil (laminae V-VI) were in disarray and surrounded by edematous extracellular spaces. The superficial neuropil (laminae I-IV), in contrast, appeared intact, but detailed examination showed indications of dendritic degeneration. Shunt procedures successfully restored the cortical mantle to near normal thickness. However, Golgi light microscopy and electron microscopy revealed that dendritic appendage morphology was altered. The results are discussed in regard to development of neuronal connectivity following shunt procedures.

Effects of risk-associated human dietary macrocomponents on processes related to carcinogenesis in human-flora-associated (HFA) rats

Dietary fat, protein and fibre have been shown to modulate cancer risk in humans and the present study examined the biological effects in human-flora-associated (HFA) rats of altering intake levels within the normal human range. Two control groups, one HFA and the other germfree (GF), consumed a human diet low in fat, fibre and beef for 4 weeks; three other groups consumed human diets similar except for independent 3-fold increases in fat, beef protein or fibre. After 2 weeks on the diets, magnetically recoverable microcapsules were given orally to the rats and subsequently recovered from the faeces to assess endogenous cross-linking agents. After 4 weeks, measurements were made of gut microfloral enzyme activities, hepatic activation of dietary mutagens and hepatic DNA adducts by 32P-postlabelling. Activation in vitro of the dietary mutagens 2-amino-3-methyl-3H-imidazo[4,5-f]quinoline (IQ) and 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP) by hepatic S9, formation of endogenous hepatic DNA adducts in vivo and the beta-glucuronidase activity of caecal contents were all increased in the sequence high fat > high fibre > high beef = control. Of the two DNA adducts found in all HFA rats, only one was present in GF controls, indicating that the human gut microflora (subject to human dietary modulation) either releases a DNA-adducting product able to act outside the gastrointestinal tract, or stimulates the generation of such a product by mammalian processes. Caecal nitrate reductase activity was highest in rats fed the high beef diet, whilst entrapment of cross-linking agents was highest in those fed the high fibre diet. These results show that risk-related components of human diets interact with human gut microflora to modulate the production of endogenous DNA-adducting and cross-linking substances.

Inhibition of dinitropyrene mutagenicity in vitro and in vivo using Salmonella typhimurium and the intrasanguinous host-mediated assay

Dinitropyrenes (DNP), present in polluted air, are potent direct-acting mutagens in Salmonella typhimurium TA98. This mutagenicity is markedly reduced in the presence of rat-liver S9 or microsomes. This has now been confirmed using mouse hepatic fractions. Since most in vitro test systems do not adequately simulate conditions encountered in the intact animal, we have investigated dinitropyrene mutagenicity to Salmonella in the host-mediated assay. 1,8-Dinitropyrene (1,8-DNP) given p.o. to BALB/c mice induced a weak mutagenic effect in S. typhimurium TA98 recovered from the liver 1 h after i.v. administration (optimum time). Over the entire dose range tested no toxicity to bacterial cells was detected. Mutation induction in vivo was dose-related with maximum response at 1 mg DNP/kg body weight. This optimum dose, however, was non-mutagenic to strains TA98/1,8-DNP6 (O-transacetylase-deficient) or TA98NR/1,8-DNP6 (nitroreductase- and O-transacetylase-deficient). 1,3-Dinitropyrene and 1,6-dinitropyrene were weakly mutagenic to TA98 at doses similar to 1,8-DNP. Studies with [14C]1,8-DNP showed that 1 h after oral dosing (1 mg/kg), over 100 ng of 1,8-DNP equivalents were present in the liver (= 0.73% dose). However, only about 5.5 ng were present in the bacterial pellet, suggesting that hepatic components in vivo, as in vitro, bind to DNP, thus interfering with its interaction with Salmonella.

Interaction with microsomal lipid as a major factor responsible for S9-mediated inhibition of 1,8-dinitropyrene mutagenicity

1,8-Dinitropyrene (1,8-DNP), present in polluted air, is a rodent carcinogen and a potent, direct-acting mutagen in salmonella typhimurium TA98. This mutagenicity is markedly reduced in the presence of mammalian hepatic S9 or microsomes. We demonstrate that at least a substantial part of this effect is attributable to non-enzymatic processes. The microsomal-dependent inhibition was unaffected by omission of an NADPH-generating system or when the cytochrome P-450 inhibitor, SKF-525A, or the cytochrome P-448 inhibitor, ellipticine, was incorporated in the metabolic activation system, suggesting that mixed function oxidases are not involved. Heat inactivation partially decreased the ability of induced S9 to reduce DNP mutagenicity. Substitution of S9 with a similar concentration of bovine serum albumin did not affect DNP activity. Thus non-specific binding to microsomal protein is not involved. However, when lipids, derived from uninduced microsomes, were added to incubations of DNP and S. typhimurium TA98, mutagenicity was decreased. Furthermore, substitution of microsomal lipids with a suspension of phosphatidylcholine (PC), a major lipid constituent of microsomes, affected DNP mutagenicity similarly. An increase in PC concentration resulted in a greater inhibitory effect. The reduction in DNP mutagenicity observed with microsomal lipids or with PC was less than that detected with uninduced S9, whilst the mutagenicity of 2-nitrofluorene was reduced to an approximately equal extent by lipids and S9. This phenomenon may be responsible for the S9-mediated detoxification of other mutagenic nitroaromatic compounds and may have important implications for mutagenicity testing.

Distribution and excretion of 1,8-dinitro[14C]pyrene in the mouse

The disposition of the environmental pollutant and potent mutagen and carcinogen, 1,8-dinitropyrene (DNP) in female BALB/c mice was investigated. In the first 48 h after oral administration of 1,8-dinitro[4,5,9,10-14C]pyrene ([14C]DNP), 42% of the dose was eliminated in the faeces and 12% in the urine. Faeces was the major pathway of excretion with 45% of the dose being eliminated by this route in 9 days. Distribution of DNP in various tissues (blood, liver, spleen, lungs, kidneys, stomach, small and large intestine) was studied over 9 days. There was a linear increase in the concentration of radioactive material in the blood, liver and kidneys up to 6 h after [14C]DNP administration, representing 0.27, 2.9 and 0.21% of the radioactive dose, respectively. The corresponding figures after 24 h decreased to 0.1, 1.6 and 0.12%, respectively. In comparison, radioactivity present in the spleen and lungs was low and did not significantly change with time. In studies with ligated sections of the gastrointestinal tract, DNP absorption was from the small and large intestine and there was none from the stomach. The rate of absorption of DNP from the small intestine was greater than that from the large intestine, although overall uptake of the compound was poor (more than 80% of the original dose was recovered from the ligated small intestine after 120 min). The data from these studies suggest that although absorption of orally administered DNP is slow, the compound or its metabolites persist in the body for long periods and the liver should be considered as the major target organ.

Activation and detoxification of 1,8-dinitropyrene by mammalian hepatic fractions in the Salmonella mutagenicity assay

1,8-Dinitropyrene (DNP) is a potent, direct-acting mutagen to Salmonella typhimurium TA98 due to activation by bacterial metabolism. We have studied the effects of uninduced and Aroclor-induced rodent liver post-mitochondrial supernatant (S9), microsomes or cytosolic preparations on its activity. With the plate incorporation protocol, the reported S9-mediated inhibition of mutagenicity was confirmed and shown to be greater after induction when equivalent levels of protein were plated. Cytosol increased mutagenicity considerably whereas the inhibitory effect of S9 could be attributed to the microsomal fraction. The activating and detoxifying capacities of the various hepatic fractions derived from male Sprague-Dawley rats and female BALB/c mice were similar. In the absence of hepatic preparations, DNP mutagenicity was much lower in TA98/1,8DNP6 (deficient in transacetylase) than in TA98, although mutagenic activity could be still increased in the former strain by addition of uninduced cytosol. When DNP was pre-incubated in a liquid assay with S9 before addition of TA98, inhibition occurred and was time dependent. Thus the overall detoxifying effect of S9 is independent of bacterial metabolism. Furthermore, inhibition occurred under conditions where cytosol and microsomal components of S9 were kept together, indicating that the detoxifying effect of the microsomes predominates. The data therefore suggest that the microsomal-mediated detoxification by S9 may be due to the presence of an inhibitory component, enzymatic or otherwise, whose concentration is increased after Aroclor-induction. Nitro-reductase activities detected in TA98 and TA98/1,8-DNP6 were 10-fold higher than those in the mammalian fractions, although the activities in the latter increased to the bacterial enzyme levels after incubation of induced S9 or microsomes, but not cytosol, with an NADPH-generating system.(ABSTRACT TRUNCATED AT 250 WORDS)

Enhanced in vivo platelet activation in subtypes of ischemic stroke

It remains uncertain whether platelet activation in ischemic stroke is contributory or secondary to brain ischemia. The efficacy of aspirin (ASA) in stroke prevention suggests that platelet activation contributes to the occurrence of stroke. On the other hand, platelet activation may be simply a generalized consequence of cerebral ischemic damage. To examine this issue, plasma levels of the platelet specific proteins beta-thromboglobulin (beta-TG) and platelet factor 4 (PF4) were measured in fifty-eight patients with various defined types of acute ischemic strokes. beta-TG was a broader indicator of platelet activation than PF4. Compared with an age-matched control group, thromboembolic and cardioembolic stroke patients had significantly elevated beta-TG levels (p less than 0.001). Also, beta-TG levels in these stroke categories were significantly higher in samples drawn within the first week after the event than in those drawn later (p less than 0.001). In contrast, beta-TG levels in lacunar stroke patients and in most TIA patients were normal. beta-TG levels did not correlate with the volume of cerebral infarction as measured by planimetry from CT scans. Moreover, beta-TG levels in patients on chronic ASA therapy at the time of stroke did not differ from those in patients of the same diagnostic categories not taking aspirin. These data indicate that platelet activation may be important in some, but not all, subtypes of ischemic stroke and that platelet activation can occur in stroke even though the platelet cyclooxygenase pathway is suppressed.

Squamous cell cancer of female urethra. Successful treatment with chemoradiotherapy

We report the case of a seventy-four-year-old woman with advanced squamous cell carcinoma of the urethra who achieved complete biopsy-proved regression of the tumor for more than thirty months after therapy with 5-fluorouracil, mitomycin-C, and radiotherapy.

Prostacyclin infusion in acute cerebral infarction

We gave prostacyclin infusions to seven patients with acute cerebral infarction. Patients without CT evidence of infarction improved, but those who already had hypodensities on CT did not benefit. Increased platelet activity, measured by plasma beta-thromboglobulin, decreased significantly (p less than 0.01) during prostacyclin administration to normal levels, but rose again after the infusion. These results indicate that prostacyclin can be given safely in doses adequate to suppress platelet function. Our findings encouraged us to proceed with a controlled trial of its clinical efficacy.

Osteogenic sarcoma producing human chorionic gonadotrophin. Case report with immunohistochemical studies

An osteogenic sarcoma occurring in a 22-year-old woman was found to be associated with production of a large amount of beta human chorionic gonadotrophin (B-hCG). Pregnancy was excluded on the basis of a normal ultrasonogram and a proliferative type endometrium obtained by curettage. A homogenate of the tumor was strongly positive for B-hCG while immunohistochemical staining of the tumor cells was strongly positive for B-hCG and negative for pregnancy associated glycoprotein. These results indicate ectopic production of hCG by the osteosarcoma.

The influence of nisoldipine--a "calcium entry blocker" on drug induced stereotyped behavior in rats

In view of potential ability of calcium entry blockers to affect Ca2+ fluxes in neurons, the effects of nisoldipine on phencyclidine (PCP) and apomorphine (APO) induced stereotyped behavior have been examined in 3 and 4 week old rats. The rats (3 and 4 weeks old) were pretreated with either 0.2 ml of saline + ethanol mixture (10:1 v/v) or nisoldipine (25 mg/kg) i.p., 5 min before the i.p. administration of PCP (5 mg/kg) or APO (10 mg/kg). While nisoldipine pretreatment significantly blocked the PCP induced stereotypy in 3 and 4 week old rats, the APO induced stereotypy was not altered. These preliminary data suggest that nisoldipine specifically blocks PCP induced stereotypy probably by antagonizing it effects at the presynaptic level. The significance of this finding in relation to mechanism of action of PCP and calcium entry blockers is discussed.

Regional localization of [14C] methylphenidate in rabbit brain

1. Neuroanatomical distribution of [14C] methylphenidate has been examined in rabbit brain following intracerebroventricular administration. 2. After about a week of implantation of cannula, in lateral ventricle, in albino rabbits, [14C] methylphenidate was injected through the cannula. The distribution of [14C] methylphenidate was examined at 15, 60 and 180 min after the injection in twelve brain regions. 3. The highest levels were observed at the first sampling time (15 min), in medulla and cervical spinal cord. Pons, caudate, tegmentum and hypothalamus also showed significant uptake of [14C] methylphenidate. Cerebral cortex and thalamus showed very low uptake. 4. The uneven distribution suggests a special affinity of methylphenidate for certain brain regions. The implications of this finding for the central actions of methylphenidate are discussed.