Cardiac Sparing with Volumetric Modulated Arc Therapy Enabled Total Body Irradiation (CS VMAT-TBI)

PURPOSE/OBJECTIVE(S)

Volumetric modulated arc therapy (VMAT) enabled total body irradiation (TBI) has replaced conventional TBI in our institution given the improved treatment accuracy, patient comfort, and dose modulation ability. The risk of cardiovascular disease is several folds higher among transplant patients who receive TBI, likely related to dose to the heart. We hypothesize that a cardiac-sparing (CS) VMAT-TBI technique is feasible and can meaningfully reduce dose to the heart while still adequately covering nearby lymphatic tissue.

MATERIALS/METHODS

VMAT-TBI is delivered via multi-isocentric external beams in a frame-based setup. Heart is contoured as per published guidelines. A lymph node contour, which includes tonsils, neck nodal stations, mediastinal, abdominal, retroperitoneal, and pelvic nodes is created. Coverage of the lymph node contour is prioritized over organ-sparing during inverse optimization; with a goal of V90% greater than 99.5% and mean dose less than 800 cGy for the lymph nodes and heart, respectively. An IRB-approved retrospective review was performed with mean heart dose collected for all patients treated with CS VMAT-TBI and compared to a representative cohort of five patients treated with VMAT-TBI without cardiac sparing.

RESULTS

Thirty-one patients were treated with CS VMAT-TBI between 2020-2022 with a median follow up time of 11.5 months. Mean heart dose was 796 ± 71 cGy in the CS VMAT-TBI compared to 1247 ± 29 cGy in the VMAT-TBI group without cardiac sparing (p < 0.001). Of those treated with CS VMAT-TBI, three patients relapsed; one relapse occurred in bone marrow only, one relapse occurred in bone marrow and cervical, thoracic, and intra-abdominal lymphoid tissues, and one patient was simulated but never received induction therapy due to overt progression. 100-day relapse-free survival and overall survival were 82.5% and 86.2%, respectively. Median survival time has not been met.

CONCLUSION

Cardiac sparing is feasible in VMAT-TBI and is associated with significant decrease in mean heart dose of ∼450 cGy. This is estimated to confer a 33.3% decreased absolute risk for lifetime major coronary events compared to patients treated with VMAT-TBI without cardiac sparing. Although limited by short follow-up time, there does not appear to be a significant risk for early relapse despite de-escalating cardiac tissue, likely due to prioritizing coverage of lymph nodes. Prospective clinical studies are needed to further validate cardiac and other organ at risk sparing VMAT-TBI techniques.

Role of Fractionation in Local Control of Spinal Metastases Treated with Stereotactic Radiosurgery

PURPOSE/OBJECTIVE(S)

Optimal fractionation of spinal stereotactic radiosurgery (SRS) for spine metastases remains unknown. Retrospective data suggest decreased local failure (LF) with fractionated SRS of brain metastases. We evaluated our institutional outcomes of spinal SRS with the hypothesis that fractionation improves the rate of local failure compared to single-fraction treatment.

MATERIALS/METHODS

This IRB-approved, retrospective analysis included patients with spine metastases treated with spinal SRS between October 2002 and November 2014 with evaluable follow-up imaging and no prior irradiation to the given segment. The exposure of interest was single- or multi-fraction SRS with a primary endpoint of the cumulative incidence of LF with death as a competing risk. We assessed bivariate associations between fractionation and single-fraction equivalent dose (SFED in Gy10) as well as high-risk features, defined as epidural extension (Bilsky Scale), paraspinous extension, and gastrointestinal (GI) vs non-GI primary. We calculated the rates of LF and vertebral body compression fracture (VCF) at 1-year, and assessed LF by fractionation when limited only to courses receiving SFED>18 Gy. We analyzed the association between fractionation and LF using subdistribution hazard ratios (SHR) estimated from competing risks regression with death as a competing risk and adjusting for lesion-specific characteristics as well as SFED to determine contribution of these variables to the estimated effect of fraction number on LF. We calculated relative attenuation for the contribution of SFED to this association, defined as [SHRfractions-SHRfractions+SFED] ÷ [SHRSFED-1].

RESULTS

In 293 patients with 516 spinal segments, lesions treated with single fraction compared to multi-fraction SRS had less epidural (19% vs 36%, p<0.001) and paraspinous (20% vs 35%, p<0.001) extension, more GI histology (17% vs 10%, p = 0.039), received a higher mean SFED (18.3 Gy vs. 16.6 Gy, p<0.001), and had a lower 1-year LF (8% vs 14%, p = 0.02), with no difference in VCF (7% vs. 5%, p = 0.38). After adjusting for high-risk features, single fraction SRS was associated with lower LF (SHR = 0.45, 95% CI 0.24-0.84, p = 0.02). After adjustment for SFED, this association of fractionation was attenuated by 53% and became insignificant (SHR = 0.78, 95% CI 0.44-1.37, p = 0.38). Overall, 1-year LF for SFED>18 Gy was 6% compared to 15% for <18 Gy (p<0.001). When limited to courses with SFED>18 Gy (n = 261), single fraction SRS had no improvement in 1-year LF compared to multi-fraction (6.6% vs 4.6%, p = 0.77).

CONCLUSION

Single fraction SRS was associated with better local control compared to multi-fraction; however, much of this association was attenuated by SFED but not by high-risk features of treated lesions. To clarify the role of fractionation, we have initiated a prospective, randomized trial of single vs. multi-fraction SRS utilizing the same SFED.

Response-Adapted Omission of Radiotherapy in Pediatric Patients with Intermediate- and High-Risk Hodgkin Lymphoma Treated per EuroNet-PHL-C1: A Single Institution Analysis of Outcomes and Patterns of Failure

PURPOSE/OBJECTIVE(S)

EuroNet-PHL-C1 demonstrated that 40% of intermediate- and high-risk pediatric Hodgkin lymphoma (HL) patients treated with OEPA-COPDAC chemotherapy achieved adequate response (AR) at early response assessment (ERA), and thus were able to omit radiotherapy (RT). However, patterns of failure with this treatment paradigm, and specifically, whether or not all initial sites of disease require RT for those with inadequate response (IR) at ERA is unknown. The purpose of our study is to examine outcomes and patterns of failure for those treated per EuroNet-PHL-C1 at our institution. Our hypothesis is that limiting RT to only sites of IR at ERA does not result in increased failures.

MATERIALS/METHODS

An IRB-approved retrospective review of all intermediate- and high-risk classical HL pediatric patients treated at our institution per EuroNet-PHL-C1 between 2015 and 2021 was performed. Patients were treated per protocol with radiation omitted for those with AR (Deauville 1-2 and >75% tumor shrinkage) at ERA (PET/CDT after 2 cycles of chemo). For those with IR who required RT, only sites of IR (Deauville 3-5) at ERA were treated using involved site radiation treatment (ISRT), instead of all initial sites of disease as on EuroNet-PHL-C1. Outcomes including overall survival (OS) and progression free survival (PFS) were calculated using Kaplan-Meier curves and patterns of failure were classified as either initial site only, new site only, or initial and new sites.

RESULTS

A total of 35 patients were identified, of which 33 had evaluable follow up with median follow up of 33 months. The median age at diagnosis was 14 (range, 4-18) and 48% were female. Of the 33, 7 (21%) had IR at ERA and thus required RT, while 26 (79%) were spared RT. In the group who received RT, 4/7 (57%) had initial B-symptoms and 4/7 (57%) had initial bulky disease, compared to 9/26 (35%) and 20/26 (77%), respectively, in those who did not receive RT. For our entire cohort, 2-year PFS and OS were 91% and 100%, respectively. For those who had RT, 2-year PFS was 83% compared to 92% in those who did not need RT. There was a total of 3 relapses (9%) at last follow up with 1/7 (14%) in those who had RT vs. 2/26 (8%) in those without RT. For the patient who relapsed after RT, relapse occurred both at initial and new sites. For the 2 who relapsed who did not receive RT, 1 was both in initial and new sites, while the other was initial site only.

CONCLUSION

At our institution, the majority of patients treated per EuroNet-PHL-C1 avoided RT with excellent outcomes. For those requiring RT, limiting RT to only sites of IR at ERA does not appear to adversely affect outcomes, though analysis is limited by the low number of failures.

Phase I Trial of 'Re-Priming' Radiation Therapy for Relapsed/Refractory Non-Hodgkin Lymphoma Patients in Incomplete Response after Chimeric Antigen Receptor T-Cell (CAR-T) Therapy

PURPOSE/OBJECTIVE(S)

Inpatients with relapsed/refractory non-Hodgkin lymphoma (R/R NHL) treated with CD19-directed CAR-T, only ∼40% achieve complete response (CR) by day 30 PET/CT evaluation. Of those who do not, the large majority (∼70%) ultimately fail, providing an ideal target for early therapeutic intervention to 're-prime' CAR-T. Preclinical and early clinical studies suggest potential synergy and immune augmentation when combining RT with CAR-T. Here we report the phase I results of a prospective phase I/II clinical trial hypothesizing that early salvage focal RT to poor responding sites of disease after CAR-T in R/R NHL patients is safe (phase I) and will improve conversion to CR by day 90 post-CAR-T PET/CT from 29% (historical control) to 58% (phase II).

MATERIALS/METHODS

Weopened a single-arm open-label phase I/II prospective clinical trial at our institution for R/R NHL patients treated with CD19-directed CAR-T with incomplete response on day 30 post-CAR-T PET/CT scan (defined as Lugano > = 4). The phase I component used a 'Rolling 6' design with 6 patients enrolled concurrently at the "definitive" dose level (40-50 Gy EQD2 [i.e., 30 Gy in 5 fractions], with de-escalation to "palliative" dose level (20-32.5 Gy EQD2 [i.e., 20 Gy in 5 fractions]) if >2 dose-limiting toxicities (DLT) observed. Hypofractionated regimens (i.e., 5 fractions) directed only to residual FDG-avid disease were recommended to minimize lymphopenia and potentially result in a more favorable immune microenvironment. DLT rate was defined within 60 days of RT by CTCAE v5.0 grade 4+ hematologic, grade 3+ dermatitis/burn, pneumonitis, enteritis, or other toxicity attributable to RT, as well as new grade 3+ cytokine release syndrome (CRS) per ASTCT consensus guidelines or grade 3+ neurotoxicity per ASTCT ICANS consensus guidelines for adults.

RESULTS

BetweenApril 2021 and July 2022, 6 patients were enrolled. All 6 patients had diffuse large B-cell lymphoma (DLBCL), with 3/6 (50%) transformed from low-grade follicular lymphoma. 2/6 had primary refractory DLBL, while the other 4/6 had median 2.5 lines of treatment prior to CAR-T. No patient had prior RT to a site of residual FDG-avid disease on day 30 post-CAR-T PET/CT. 5/6 patients were treated to 30 Gy in 5 fractions, with the remainder patient treated to 36 Gy in 10 fractions. No grade 3+ DLTs related to RT were observed in the 60-day post-RT period. RT related toxicities included grad 1 alopecia, grade 1 radiation pneumonitis, grade 1 nausea & vomiting, and grade 2 skin infection.

CONCLUSION

Early salvage focal "definitive" dose RT to sites of incomplete response on day 30 post-CAR-T PET/CT for R/R/ NHL patients was safe with no de-escalation of dose needed. This dose will used in the subsequent phase II component of the trial.

The Changing Profile of Academic Radiation Oncology Leaders: Updates over the Past Decade

PURPOSE/OBJECTIVE(S)

To report objective characteristics of program directors (PDs) and chairpersons and examine contemporary trends of their demographic and academic profiles from 2013 to 2023. We hypothesize that there are significant changes in the profiles of our radiation oncology leaders over the past decade.

MATERIALS/METHODS

A total of 89 PDs and 85 chairpersons in the Accreditation Council for Graduate Medical Education (ACGME)-approved residency programs in the U.S were queried for analysis. Demographic data on race, ethnicity, post graduate training, years in practice were obtained from publicly available online resources (e.g., institutional websites and online networking services for physicians). Variables on academic productivity and professional accolades included Hirsh-index, National Institute of Health (NIH) research grant (R), the ASTRO fellowship designation, and leadership positions in professional society meetings. Descriptive analyses, including Fisher's exact tests, were performed to compare findings from the published article in 2013 on this topic (Wilson LD et al. IJROBP 2013).

RESULTS

A total of 36 out of 89 PDs (40.4%) and 11 out of 85 chairpersons (12.8%) were females, revealing higher proportion of females from the initial analysis: 40.4 vs. 24.1% for PDs (p = 0.025) and 12.8 vs. 9.2% for chairpersons (p = 0.618). 29 out of 89 (32.6%) PDs and 30 out of 85 (35.3%) chairpersons were non-White. The median length of practice for PDs and chairpersons were 11 and 29 years, respectively. 38 out of 89 PDs (42.7%) and 11 out of 85 (12.9%) chairpersons were employed at the institution of their training. 7 out of 89 (7.9%) for PDs and 51 out of 85 (60.0%) for chairpersons were awarded FASTRO designation. Median H-index showed increasing trends for PDs (14.5 vs 9) and chairpersons (40 vs 29) from the initial analysis.

CONCLUSION

While most PDs and chairpersons are males, female representation has increased in radiation oncology leadership in the last 10 years, most notably among PDs. Academic productivity among our leaders has also increased. These trends highlight the changes in the landscape of our leadership characteristics.

ACR-ARS Practice Parameter for the Performance of Total Body Irradiation

OBJECTIVES

This practice parameter was revised collaboratively by the American College of Radiology (ACR) and the American Radium Society (ARS). This practice parameter provides updated reference literature regarding both clinical-based conventional total body irradiation and evolving volumetric modulated total body irradiation.

METHODS

This practice parameter was developed according to the process described under the heading The Process for Developing ACR Practice Parameters and Technical Standards on the ACR website ( https://www.acr.org/Clinical-Resources/Practice-Parameters-and-Technical-Standards ) by the Committee on Practice Parameters-Radiation Oncology of the ACR Commission on Radiation Oncology in collaboration with the ARS.

RESULTS

This practice parameter provides a comprehensive update to the reference literature regarding conventional total body irradiation and modulated total body irradiation. Dependence on dose rate remains an active area of ongoing investigation in both the conventional setting (where instantaneous dose rate can be varied) and in more modern rotational techniques, in which average dose rate is the relevant variable. The role of imaging during patient setup and the role of inhomogeneity corrections due to computer-based treatment planning systems are included as evolving areas of clinical interest notably surrounding the overall dose inhomogeneity. There is increasing emphasis on the importance of evaluating mean lung dose as it relates to toxicity during high-dose total body irradiation regimens.

CONCLUSIONS

This practice parameter can be used as an effective tool in designing and evaluating a total body irradiation program that successfully incorporates the close interaction and coordination among the radiation oncologists, medical physicists, dosimetrists, nurses, and radiation therapists.

Serious Illness Communication Training Among Radiation Oncology Residents

PURPOSE

Education and specific training on serious illness communication skills for radiation oncology residents is lacking. The Accreditation Council for Graduate Medical Education requires radiation oncology residents to demonstrate interpersonal and communication skills; however, implementing specific training to address this poses an ongoing challenge. This study assesses the feasibility and effectiveness of a radiation oncology specific serious illness communication curriculum at a single radiation oncology residency program.

METHODS AND MATERIALS

The primary objectives were to assess observable communication skills among radiation oncology residents and their perceived level of preparedness and comfort with patient encounters surrounding serious illness. Each resident participated in a baseline simulated patient encounter. Two virtual half-day experience-based learning sessions led by faculty experts trained in teaching serious illness communication were held. The training consisted of brief didactic teaching, with the emphasis on small group guided practice with simulated patients in scenarios specific to radiation oncology. Each resident participated in a postcourse simulated patient encounter. Three blinded faculty trained in serious illness communication completed objective assessments of observable communication skills to compare pre- and postcourse performance.

RESULTS

A t test based on validated assessments reviewed by blinded faculty demonstrated significant improvement in overall observable communication skills among radiation oncology residents in the postcourse encounter compared with the precourse encounter (P = .0067). Overall, 8 of 9 (89%) residents felt more comfortable and prepared with radiation oncology-specific serious illness communication after the course compared with prior. The simulated patients rated the overall average resident performance higher on the postcourse assessment (Likert 4.89/5) compared with the precourse assessment (Likert 4.09/5), which trended toward a significant improvement (P = .0515).

CONCLUSIONS

Radiation oncology residents had a significant improvement in observable communication skills after participating in an experience-based training curriculum. This course can serve as an adaptable model that may be implemented by other radiation oncology residency programs.

Abstract A15: Clinico-pathologic and molecular characteristics of primary extranodal germinal-center B-cell like diffuse large B-cell lymphoma (EN GCB-DLBCL)

Background: Diffuse large B-cell lymphoma (DLBCL) is a heterogeneous disease and in 30-40% cases can present or relapse at extranodal sites. Primary extranodal DLBCL (EN-DLBCL) is defined as disease presenting as clinically dominant extranodal masses with no or only minor nodal disease. EN-DLBCL is predominantly of the activated B-cell (ABC) and less commonly of germinal center B-cell (GCB) like DLBCL subtype. We aimed to identify genetic characteristics of EN GCB-DLBCL to gain insights into extranodal tropism and aggressive clinical behavior. Methods: Patient data was collected via retrospective chart review. Inclusion criteria consisted of pathologically confirmed diagnosis of GCB-DLBCL by the Hans algorithm, extra-nodal involvement at diagnosis or relapse, and availability of next-generation sequencing (NGS). Overall (OS) and progression-free survival (PFS) were analyzed using the Kaplan-Meier method. Results: Fifteen patients were identified. The median age at diagnosis was 64 years (range 33-89) and majority were men (62.5%). Two patients had purely nodal disease at presentation that relapsed at EN sites, while the remainder (13/15) had predominantly EN disease. EN sites included central nervous system [CNS] (n = 5), bone marrow (n = 4), epidural (n=4), bone (2), paranasal sinus (1), testes (1), stomach (n = 2), lung/pleura (n=2), and liver (n=3). Nine patients had disease in multiple EN sites. All patients had advanced stage disease and median IPI score was 3 (range 3-4). On FISH/cytogenetic analysis, two patients had MYC and four patients had BCL2 rearrangements. Copy gains in BCL6, BCL2 and MYC were seen in 2, 1 and 4 patients respectively. No patients had evidence of MYC and BCL2 and/or BCL6 rearrangements (double hit). TP53 deletion was seen in 1 patient. On NGS, prominent gene mutations identified were KMTD2 (8/15, 53%), TP53 (5/15, 33%), TNFRSF14 (4/15, 27%), and evidence of aneuploidy with abnormalities in chromosome 12 (5/15, 33%), chromosome 6 (4/15, 27%), and chromosome 8 (4/15, 27%), including both losses and gains of function. Notably, MYD88 (3/15, 20%), CARD11 (2/15, 13%), and IRF4 (2/15, 15%) mutations, representative of BCR/TLR4 pathway activation and NF-kB signaling were seen at initial presentation. All patients were treated with chemo-immunotherapies incorporating CNS prophylaxis and 2 patients received salvage CAR T-cell therapy. Median OS was 1.3 years and median PFS was 11.3 months. Nine patients (63%) progressed, with CNS relapses in 5 and of these, 7 patients died. Conclusions: This study shows that EN GCB-DLBCL is molecularly similar to EN ABC-DLBCL; specifically, activation of NF-kB pathway signaling through gene mutations involving the MCD (MyD88/CD79B) cluster is prominent, and this potentially enables extranodal tropism. The complex karyotype and TP53 mutations may contribute to chemoresistance and aggressive disease biology. Our results provide valuable molecular information and can aid in personalizing treatment strategies for this uncommon, aggressive DLBCL subset.

Citation Format: Akshat Patel, Brian Lue, Kiran A Kumar, Farrukh T Awan, Jeffrey Gagan, Weina Chen, Praveen Ramakrishnan Geethakumari. Clinico-pathologic and molecular characteristics of primary extranodal germinal-center B-cell like diffuse large B-cell lymphoma (EN GCB-DLBCL) [abstract]. In: Proceedings of the Third AACR International Meeting: Advances in Malignant Lymphoma: Maximizing the Basic-Translational Interface for Clinical Application; 2022 Jun 23-26; Boston, MA. Philadelphia (PA): AACR; Blood Cancer Discov 2022;3(5_Suppl):Abstract nr A15.

Abstract A40: Evaluation of the tumor microenvironment in mycosis fungoides using the PanCancer IO 360™ assay and nCounter® platform

BACKGROUND: Alterations in the tumor microenvironment (TME) can result in a “T-cell inflamed” TME, which is characterized by activation of the PD1/PD-L1 pathway, immunosuppression, and production of anergic, “exhausted” CD8(+)-T-cells. Similar alterations in the TME of Mycosis Fungoides (MF) have been linked to disease progression. However, the relationship between progression and the TME in MF remains incompletely understood. We aimed to further study the TME in MF using the PanCancer IO 360™ 750-gene expression panel and nCounter® platform (Nanostring; Seattle, WA). DESIGN: Clinical and laboratory data from the electronic medical record were reviewed in combination with microscopic review of biopsies from 27 patients to confirm diagnosis of MF and assign samples as “low-grade” (patch/plaque; n=8) or “high-grade” (tumor/large cell transformation, n=19). Patients were also classified as having “limited stage” (TNMB1 &lt;1B, n=8) or “advanced stage” (TNMB1 &gt;1B, n=19) disease. All patients received prior, heterogenous treatment, but no patients received prior anti-PD1 therapy. RNA was extracted from formalin-fixed, paraffin-embedded (FFPE), punch biopsy sections and analyzed per manufacturer’s instructions. Gene expression scores (log2) and a “tissue inflammation score” (TIS) were calculated for each sample. A TIS of &gt;5 has been associated with the presence of a “T-cell inflamed” microenvironment. Samples scores were compared by histologic group and disease stage as described above. RESULTS: Twenty-nine of 30 samples had sufficient RNA integrity for analysis. TIS was &gt;5 in 26/30 samples (median, 7.6; range, 4.3-9.3). No significant differences in TIS were identified between low-grade/limited-stage and high-grade/advanced-stage samples. High-grade samples had significantly increased expression of PD1 and higher amounts of exhausted CD8(+)-cells than low-grade samples (p= 0.015, 0.027). Low-grade samples showed significantly higher expression of ARG1, B7-H3, and genes associated with tissue hypoxia. Expression of genes associated with tumor proliferation was higher in high-grade lesions (p= 0.0019). Limited stage samples showed higher levels of endothelial cells, mast cells, and T-regulatory cells (p=0.033, 0.024, 0.004,) than advanced stage samples. Proliferation, PD1, and exhausted CD8 scores trended higher in advanced stage disease but did not reach statistical significance. CONCLUSION: Our findings indicate that the IO 360™ panel provides comprehensive analysis of the TME in MF. Most samples showed a TIS of &gt;5, suggesting a T-cell inflamed TME in MF. Increased PD1 and exhausted CD8(+) cells were found in high-grade lesions, supporting a role for this pathway in progression. Increased expression of factors associated with angiogenesis (endothelial cells, ARG1) and immunosuppression (B7-H3, tissue hypoxia, mast cells, T-regulatory cells) suggest these mechanisms may play a role in early stages of disease. These findings highlight the complex and dynamic nature of the TME during MF progression, and the need for further study.

Citation Format: Stanton Miller, Akshat Patel, Kiran A Kumar, Farrukh Awan, Heather W Goff, Travis Vandergriff, Marisa Juntilla, Franklin Fuda, Weina Chen, Jesse M Jaso. Evaluation of the tumor microenvironment in mycosis fungoides using the PanCancer IO 360™ assay and nCounter® platform [abstract]. In: Proceedings of the Third AACR International Meeting: Advances in Malignant Lymphoma: Maximizing the Basic-Translational Interface for Clinical Application; 2022 Jun 23-26; Boston, MA. Philadelphia (PA): AACR; Blood Cancer Discov 2022;3(5_Suppl):Abstract nr A40.

A Combined Biomarker of Bright CD38 and MYC ≥55% Is Highly Predictive of Double-/Triple-Hit High-Grade B-Cell Lymphoma

OBJECTIVES

Diagnosis of high-grade B-cell lymphoma with MYC and BCL2 or BCL6 rearrangements (double-/triple-hit lymphoma [DTHL]) appears to mandate fluorescence in situ hybridization (FISH) testing for all large B-cell lymphoma (LBCL). Given the low incidence of DTHL, we aimed to identify flow cytometry (FC) and immunohistochemistry (IHC) features of DTHL that could be used to develop an optimal screening strategy. This combined FC-IHC approach has not yet been studied.

METHODS

We compared features of 40 cases of DTHL and 39 cases of diffuse LBCL (DLBCL) without MYC rearrangement.

RESULTS

Bright CD38 expression (CD38bright) by FC, high MYC expression (≥55%), and double-expressor phenotype by IHC were significantly associated with DTHL. The biomarker combining FC and IHC, CD38bright and/or MYC ≥55%, was superior to FC and IHC markers alone in predicting DTHL. Restricting FISH testing to approximately 25% of LBCL based on CD38brightand/or MYC ≥55% would detect approximately 95% of DTHL-BCL2 and approximately 75% of DHL-BCL6.

CONCLUSIONS

Our study demonstrated that the novel biomarker of CD38bright and/or MYC ≥55% is highly predictive of DTHL. Awareness of the advantages and limitations of this screening strategy would facilitate development of a rational diagnostic workflow to provide high-quality patient care.

Primary central nervous system lymphoma: a real-world comparison of therapy access and outcomes by hospital setting

Background

This study analyzes sociodemographic barriers for primary CNS lymphoma (PCNSL) treatment and outcomes at a public safety-net hospital versus a private tertiary academic institution. We hypothesized that these barriers would lead to access disparities and poorer outcomes in the safety-net population.

Methods

We reviewed records of PCNSL patients from 2007-2020 (n = 95) at a public safety-net hospital (n = 33) and a private academic center (n = 62) staffed by the same university. Demographics, treatment patterns, and outcomes were analyzed.

Results

Patients at the safety-net hospital were significantly younger, more commonly Black or Hispanic, and had a higher prevalence of HIV/AIDS. They were significantly less likely to receive induction chemotherapy (67% vs 86%, P = .003) or consolidation autologous stem cell transplantation (0% vs. 47%, P = .001), but received more whole-brain radiation therapy (35% vs 16%, P = .001). Younger age and receiving any consolidation therapy were associated with improved progression-free (PFS, P = .001) and overall survival (OS, P = .001). Hospital location had no statistical impact on PFS (P = .725) or OS (P = .226) on an age-adjusted analysis.

Conclusions

Our study shows significant differences in treatment patterns for PCNSL between a public safety-net hospital and an academic cancer center. A significant survival difference was not demonstrated, which is likely multifactorial, but likely was positively impacted by the shared multidisciplinary care delivery between the institutions. As personalized therapies for PCNSL are being developed, equitable access including clinical trials should be advocated for resource-limited settings.

Lymphomatoid granulomatosis of the central nervous system (CNS-LYG) posing a management challenge

Isolated central nervous system lymphomatoid granulomatosis (CNS-LYG) can mimic aggressive glioblastomas. We describe a complex presentation of CNS-LYG coexisting with immune thrombocytopenia successfully managed with rituximab and ultra-low-dose radiation therapy.

Insights from a Pan India Sero-Epidemiological survey (Phenome-India Cohort) for SARS-CoV2

To understand the spread of SARS-CoV2, in August and September 2020, the Council of Scientific and Industrial Research (India) conducted a serosurvey across its constituent laboratories and centers across India. Of 10,427 volunteers, 1058 (10.14%) tested positive for SARS-CoV2 anti-nucleocapsid (anti-NC) antibodies, 95% of which had surrogate neutralization activity. Three-fourth of these recalled no symptoms. Repeat serology tests at 3 (n = 607) and 6 (n = 175) months showed stable anti-NC antibodies but declining neutralization activity. Local seropositivity was higher in densely populated cities and was inversely correlated with a 30-day change in regional test positivity rates (TPRs). Regional seropositivity above 10% was associated with declining TPR. Personal factors associated with higher odds of seropositivity were high-exposure work (odds ratio, 95% confidence interval, p value: 2.23, 1.92-2.59, <0.0001), use of public transport (1.79, 1.43-2.24, <0.0001), not smoking (1.52, 1.16-1.99, 0.0257), non-vegetarian diet (1.67, 1.41-1.99, <0.0001), and B blood group (1.36, 1.15-1.61, 0.001).

Long-Term Update of Stereotactic Radiosurgery for Benign Spinal Tumors

BACKGROUND

Stereotactic radiosurgery (SRS) for benign intracranial tumors is an established standard of care. The widespread implementation of SRS for benign spinal tumors has been limited by lack of long-term data.

OBJECTIVE

To update our institutional experience of safety and efficacy outcomes after SRS for benign spinal tumors.

METHODS

We performed a retrospective cohort study of 120 patients with 149 benign spinal tumors (39 meningiomas, 26 neurofibromas, and 84 schwannomas) treated with SRS between 1999 and 2016, with follow-up magnetic resonance imaging available for review. The primary endpoint was the cumulative incidence of local failure (LF), with death as a competing risk. Secondary endpoints included tumor shrinkage, symptom response, toxicity, and secondary malignancy.

RESULTS

Median follow-up was 49 mo (interquartile range: 25-103 mo, range: 3-216 mo), including 61 courses with >5 yr and 24 courses with >10 yr of follow-up. We observed 9 LF for a cumulative incidence of LF of 2%, 5%, and 12% at 3, 5, and 10 yr, respectively. Excluding 10 tumors that were previously irradiated or that arose within a previously irradiated field, the 3-, 5-, and 10-yr cumulative incidence rates of LF were 1%, 2%, and 8%, respectively. At last follow-up, 35% of all lesions had decreased in size. With a total of 776 patient-years of follow-up, no SRS-related secondary malignancies were observed.

CONCLUSION

Comparable to SRS for benign intracranial tumors, SRS provides longer term local control of benign spinal tumors and is a standard-of-care alternative to surgical resection.

Local control and toxicity outcomes of stereotactic radiosurgery for spinal metastases of gastrointestinal origin

OBJECTIVE

Colorectal cancer (CRC) and other gastrointestinal (GI) cancers are believed to have greater radioresistance than other histologies. The authors report local control and toxicity outcomes of stereotactic radiosurgery (SRS) to spinal metastases from GI primary cancers.

METHODS

A retrospective single-center review was conducted of patients with spinal metastases from GI primary cancers treated with SRS from 2004 to 2017. Patient demographics and lesion characteristics were summarized using medians, interquartile ranges (IQRs), and proportions. Local failure (LF) was estimated using the cumulative incidence function adjusted for the competing risk of death and compared using Gray's test for equality. Multivariable analyses were conducted using Cox proportional hazard models, adjusting for death as a competing risk, on a per-lesion basis. Patients were stratified in the Cox model to account for repeated measures for clustered outcomes. Median survival was calculated using the Kaplan-Meier method.

RESULTS

A total of 74 patients with 114 spine lesions were included in our analysis. The median age of the cohort was 62 years (IQR 53-70 years). Histologies included CRC (46%), hepatocellular carcinoma (19%), neuroendocrine carcinoma (13%), pancreatic carcinoma (12%), and other (10%). The 1- and 2-year cumulative incidence rates of LF were 24% (95% confidence interval [CI] 16%-33%) and 32% (95% CI 23%-42%), respectively. Univariable analysis revealed that older age (p = 0.015), right-sided primary CRCs (p = 0.038), and single fraction equivalent dose (SFED; α/β = 10) < 20 Gy (p = 0.004) were associated with higher rates of LF. The 1-year cumulative incidence rates of LF for SFED < 20 Gy10 versus SFED ≥ 20 Gy10 were 35% and 7%, respectively. After controlling for gross tumor volume and prior radiation therapy to the lesion, SFED < 20 Gy10 remained independently associated with worse LF (hazard ratio 2.92, 95% CI 1.24-6.89, p = 0.014). Toxicities were minimal, with pain flare observed in 6 patients (8%) and 15 vertebral compression fractures (13%).

CONCLUSIONS

Spinal metastases from GI primary cancers have high rates of LF with SRS at a lower dose. This study found that SRS dose is a significant predictor of failure and that prescribed SFED ≥ 20 Gy10 (biological equivalent dose ≥ 60 Gy10) is associated with superior local control.

Reliability and validity of PHQ-9 when administered by health workers for depression screening among women in primary care

BACKGROUND

Depression is twice more prevalent among women but remains unidentified in primary care.

OBJECTIVE

We aimed to estimate the reliability and validity of PHQ-9, when administered by health workers, a cadre of public health staff, posted in primary health centres. We translated PHQ-9 to Malayalam, a language spoken by 30 million people in Kerala, India. Health workers administered PHQ-9 to women (n = 238) aged 18-60 years in a high prevalent primary care setting. Mini International Neuropsychiatric Interview (MINI) was administered by the psychiatrist on the same day to diagnose depressive disorder. Two health workers administered PHQ-9, independently, in a subset of 21 women.

RESULTS

The internal consistency reliability (Cronbach's alpha 0.89) and inter-rater reliability (intra class correlation coefficient, 0.94; 95% CI, 0.86-0.95) were high. On ROC analysis, area under curve was 0.92 (95% CI 0.88-0.96). For a cut-off score of ≥9, PHQ-9 had a sensitivity of 82.5%, (95% CI, 72.4-92.6), specificity of 90.1% (95% CI, 84.5-95.6%), positive predictive value of 73.4% (95% CI, 62.4-84.4%) and negative predictive value of 93.9% (95% CI, 90.2-97.6%). The accuracy was 88.2% (84.0-92.4%) and positive likelihood ratio was 8.3. Factor analysis supported a single factor, with eigen value above 1, with high loading for all items (0.73-0.79), except item related to appetite (0.58). This explained 62% of variance in the data. Prevalence of MINI diagnosed depressive disorders was 25%.

CONCLUSION

When administered by health workers, PHQ-9 has good reliability and at cut off score ≥9, it has good validity to identify depression in primary care.

Cost-effectiveness of radiation and chemotherapy for high-risk low-grade glioma

Background

The addition of procarbazine, lomustine, vincristine (PCV) chemotherapy to radiotherapy (RT) for patients with high-risk (≥40 y old or subtotally resected) low-grade glioma (LGG) results in an absolute median survival benefit of over 5 years. We evaluated the cost-effectiveness of this treatment strategy.

Methods

A decision tree with an integrated 3-state Markov model was created to follow patients with high-risk LGG after surgery treated with RT versus RT+PCV. Patients existed in one of 3 health states: stable, progressive, or dead. Survival and freedom from progression were modeled to reflect the results of RTOG 9802 using time-dependent transition probabilities. Health utility values and costs of care were derived from the literature and national registry databases. Analysis was conducted from the health care perspective. Deterministic and probabilistic sensitivity analysis explored uncertainty in model parameters.

Results

Modeled outcomes demonstrated agreement with clinical data in expected benefit of addition of PCV to RT. The addition of PCV to RT yielded an incremental benefit of 4.77 quality-adjusted life-years (QALYs) (9.94 for RT+PCV vs 5.17 for RT alone) at an incremental cost of $48635 ($188234 for RT+PCV vs $139598 for RT alone), resulting in an incremental cost-effectiveness ratio of $10186 per QALY gained. Probabilistic sensitivity analysis demonstrates that within modeled distributions of parameters, RT+PCV has 99.96% probability of being cost-effectiveness at a willingness-to-pay threshold of $100000 per QALY.

Conclusion

The addition of PCV to RT is a cost-effective treatment strategy for patients with high-risk LGG.

Minimally Differentiated Acute Myeloid Leukemia: A Morphologic, Cytochemical and Ultrastructural Study

Seven of 368 cases of acute myeloid leukemia (AML) could not be subclassified by routine morphologic, cytochemical and immunologic analyses during the period January 1989 to December 1990. Further investigations including ultrastructural examination, anti-myeloperoxidase and myeloid specific antigen analysis were carried out in all these patients and they were classified as AML-MO, as per the FAB criteria. Morphologically these blasts resembled ALL-L2/AML-M1. Cytochemlcally they were negative for Sudan black, myeloperoxidase, periodic acid-Schiff, and non-specific esterase. On initial immunophenotypic analysis, they could not be classified Into B, T or myeloid lineages. Further investigations revealed CD13 and CD33 positivity in 4 of 6 patients. Anti-myeloperoxidase was positive in 6 of 6 patients and ultrastructural examination revealed myeloperoxidase-positive blasts in 6 of 7 cases. Cytogenetic analysis done in one patient revealed 60 % abnormal metaphases. Six of 7 cases were treated with aggressive chemotherapy. One patient achieved complete remission but relapsed after 6 months, whereas others were resistant to treatment. Hence we conclude that an aggressive investigative and therapeutic approach is required to identify and treat AML-MO.

A Pilot Study Evaluating the Use of Dynamic Contrast-Enhanced Perfusion MRI to Predict Local Recurrence After Radiosurgery on Spinal Metastases

Purpose:

Dynamic contrast-enhanced magnetic resonance imaging offers noninvasive characterization of the vascular microenvironment and hemodynamics. Stereotactic radiosurgery, or stereotactic body radiation therapy, engages a vascular component of the tumor response which may be detectable using dynamic contrast-enhanced magnetic resonance imaging. The purpose of this study is to examine whether dynamic contrast-enhanced magnetic resonance imaging can be used to predict local tumor recurrence in patients with spinal bone metastases who undergo high-dose radiotherapy with stereotactic radiosurgery.

Materials and Methods:

We conducted a study of 30 patients with spinal metastases who underwent dynamic contrast-enhanced magnetic resonance imaging before and after radiotherapy. Twenty patients received single-fraction stereotactic radiosurgery (24 Gy), while 10 received hypofractionated stereotactic radiosurgery (3-5 fractions, 27-30 Gy total). Kaplan-Meier analysis was used to estimate the actuarial local recurrence rates. Two perfusion parameters (K^trans: permeability and V_p: plasma volume) were measured for each metastasis. Percentage change in parameter values from pre- to posttreatment was calculated and compared.

Results:

At 20-month median follow-up, 5 of the 30 patients had pathological evidence of local recurrence. One- and 3-year actuarial local recurrence rates were 24% and 44% for the hypofractionated stereotactic radiosurgery cohort versus 5% and 16% for the single-fraction stereotactic radiosurgery cohort (P = .20). The average change in V_p and K^trans for patients without local recurrence versus those with local recurrence was −76% and −66% versus +28% and −14% (P < .01 for both). With a cutoff point of −20%, V_p had a sensitivity, specificity, positive predictive value, and negative predictive value of 100%, 98%, 91%, and 100%, respectively, for the detection of local recurrence following high-dose radiotherapy. Using this definition, dynamic contrast-enhanced magnetic resonance imaging identified local recurrence up to 18 months (mean [standard deviation], 6.6 [6.8] months) earlier than standard magnetic resonance imaging.

Conclusions:

We demonstrated that changes in perfusion parameters, particularly V_p, after high-dose radiotherapy to spinal bone metastases were predictive of local tumor recurrence. These changes predicted local recurrence on average >6 months earlier than standard imaging did.

Pre-treatment non-target lung FDG-PET uptake predicts symptomatic radiation pneumonitis following Stereotactic Ablative Radiotherapy (SABR)

PURPOSE

To determine if pre-treatment non-target lung FDG-PET uptake predicts for symptomatic radiation pneumonitis (RP) following lung stereotactic ablative radiotherapy (SABR).

METHODS

We reviewed a 258 patient database from our institution to identify 28 patients who experienced symptomatic (grade ⩾ 2) RP after SABR, and compared them to 57 controls who did not develop symptomatic RP. We compared clinical, dosimetric and functional imaging characteristics between the 2 cohorts including pre-treatment non-target lung FDG-PET uptake.

RESULTS

Median follow-up time was 26.9 months. Patients who experienced symptomatic RP had significantly higher non-target lung FDG-PET uptake as measured by mean SUV (p < 0.0001) than controls. ROC analysis for symptomatic RP revealed area under the curve (AUC) of 0.74, with sensitivity 82.1% and specificity 57.9% with cutoff mean non-target lung SUV > 0.56. Predictive value increased (AUC of 0.82) when mean non-target lung SUV was combined with mean lung dose (MLD). We developed a 0-2 point model using these 2 variables, 1 point each for SUV > 0.56 or MLD > 5.88 Gy equivalent dose in 2 Gy per fraction (EQD2), predictive for symptomatic RP in our cohort with hazard ratio 10.01 for score 2 versus 0 (p < 0.001).

CONCLUSIONS

Patients with elevated pre-SABR non-target lung FDG-PET uptake are at increased risk of symptomatic RP after lung SABR. Our predictive model suggests patients with mean non-target lung SUV > 0.56 and MLD > 5.88 Gy EQD2 are at highest risk. Our predictive model should be validated in an external cohort before clinical implementation.

Tracheal Diverticulum Following Paratracheal Hypofractionated Radiotherapy in the Setting of Prior and Subsequent Bevacizumab

We present the case of a 63-year-old woman with limited metastatic colorectal cancer to the lungs and liver treated with FOLFIRI-bevacizumab, followed by consolidative hypofractionated radiotherapy to right paratracheal metastatic lymphadenopathy. We treated the right paratracheal site with 60 Gy in 15 fractions (70 Gy equivalent dose in 2 Gy fractions). The patient tolerated the treatment well, and six months later started a five-month course of FOLFIRI-bevacizumab for new metastatic disease. She presented to our clinic six months after completing this, complaining of productive cough with scant hemoptysis, and was found to have localized tracheal wall breakdown and diverticulum in the region of prior high-dose radiation therapy, threatening to progress to catastrophic tracheovascular fistula. This was successfully repaired surgically after a lack of response to conservative measures. We urge caution in treating patients with vascular endothelial growth factor (VEGF) inhibitors in the setting of hypofractionated radiotherapy involving the mucosa of tubular organs, even when these treatments are separated by months. Though data is limited as to the impact of sequence, this may be particularly an issue when VEGF inhibitors follow prior radiotherapy.

Image-guided radiation therapy for prostate cancer: A computed tomography-based assessment of fiducial marker migration between placement and 7 days

PURPOSE

This study was conducted to determine whether clinically significant fiducial marker migration occurs immediately after prostatic implantation.

METHODS AND MATERIALS

One hundred patients with transperineal (n = 39) or transrectal (n = 61) placement of 3 gold fiducial markers underwent computed tomography scans on day 0 (after placement) and day 7 (at radiation planning). Each marker was marked as a point of interest in a treatment planning system. An automated point-based algorithm was then used to coregister the day 0 and day 7 images by matching the markers through rigid translations and rotations. The mean distance between fiducial pairs (d¯) was recorded to assess the degree of seed migration. Prostate contours were delineated, and the day 0 prostate volumes were uniformly expanded by 1, 3, and 5 mm. The percentage of the day 7 prostate volume covered by each day 0 prostate with expansion was calculated to assess whether prostate contours, if performed on day 0, would adequately cover the prostate on day 7.

RESULTS

The average d¯ for all patients was 0.78 ± 0.45 mm; only 1 patient had d¯ > 2 mm. Placement technique, hormonal therapy, prostate size, and marker distance from the capsule were not associated with d¯ (P > .05). The mean percentages of day 7 prostate volumes covered by the day 0 prostate plus 1, 3, and 5 mm were 98.3%, 99.8%, and 100%, respectively. With an expansion of 3 mm, 98% of men had >95% of day 0 volume covered; with an expansion of 5 mm, 100% of men had 100% of the day 0 volume covered.

CONCLUSIONS

There is minimal change in the relative positions of fiducial markers (average d¯ < 1.0 mm) 1 week after placement. A 1- to 3-mm expansion would account for the variation in seed position for the vast majority of cases. These results suggest that planning could be performed on the day of implantation without adverse consequence.

Variations in the cone packing density with eccentricity in emmetropes

AIM

To describe the parafoveal cone arrangement in emmetropic subjects and its variations with eccentricity, meridians and change in axial length in Indian eyes.

METHODS

We imaged 25 subjects using compact adaptive optics (AO) retinal camera prototype, the rtx1. Imaging was done at 1, 2, and 3° eccentricity from the fovea in four meridians: nasal, temporal, superior, and inferior.

RESULTS

A statistically significant drop in the cone packing density was observed from 2 to 3° (2° eccentricity=25 350/mm(2) (5300/mm(2), 8400-34 800/mm(2)) 3° eccentricity=20 750/mm(2) (6000 mm(2), 9000-33 670/mm(2))) P<0.05. The spacing correspondingly increased with increase in distance from the fovea (2° eccentricity=6.9 μm (0.70 μm, 5.95-11.6 μm)) and 3°eccentricity=7.80 μm (1.00 μm, 6.5-13.5 μm) P<0.05. As the axial length increases, the cone density significantly decreases. Interocular variations were noted.

CONCLUSION

With the advent of AO, visualization at the cellular level is now possible. Understanding the photoreceptor mosaic in the parafoveal space in terms of its density, spacing, and arrangement is crucial so as to detect early pathology and intervene appropriately. Newer therapeutic modalitites that are targeted at the cellular level like yellow micropulse laser, stem cells, gene therapy and so on may be better monitored in terms of safety and efficacy.

Antioxidant and antimicrobial activities of Bauhinia racemosa L. stem bark

The present study was carried out to evaluate the antioxidant and antimicrobial activities of a methanol extract of Bauhinia racemosa (MEBR) (Caesalpiniaceae) stem bark in various systems. 1,1-Diphenyl-2-picryl-hydrazyl (DPPH) radical, superoxide anion radical, nitric oxide radical, and hydroxyl radical scavenging assays were carried out to evaluate the antioxidant potential of the extract. The antioxidant activity of the methanol extract increased in a concentration-dependent manner. About 50, 100, 250, and 500 microg MEBR inhibited the peroxidation of a linoleic acid emulsion by 62.43, 67.21, 71.04, and 76.83%, respectively. Similarly, the effect of MEBR on reducing power increased in a concentration-dependent manner. In DPPH radical scavenging assays the IC50 value of the extract was 152.29 microg/ml. MEBR inhibited the nitric oxide radicals generated from sodium nitroprusside with an IC50 of 78.34 microg/ml, as opposed to 20.4 microg/ml for curcumin. Moreover, MEBR scavenged the superoxide generated by the PMS/NADH-NBT system. MEBR also inhibited the hydroxyl radical generated by Fenton's reaction, with an IC50 value of more than 1000 microg/ml, as compared to 5 microg/ml for catechin. The amounts of total phenolic compounds were also determined and 64.7 microg pyrocatechol phenol equivalents were detected in MEBR (1 mg). The antimicrobial activities of MEBR were determined by disc diffusion with five Gram-positive, four Gram-negative and four fungal species. MEBR showed broad-spectrum antimicrobial activity against all tested microorganisms. The results obtained in the present study indicate that MEBR can be a potential source of natural antioxidant and antimicrobial agents.

Antibacterial potential of an antispasmodic drug dicyclomine hydrochloride

BACKGROUND & OBJECTIVES

Several compounds are known to possess antimicrobial activity in addition to their predesignated pharmacological actions. In the present study, dicyclomine hydrochloride, an antispasmodic drug, was tested for possible antimicrobial property in vitro and in vivo.

METHODS

The minimum inhibitory concentration (MIC) of dicyclomine against the bacteria was determined by agar and broth dilution methods in vitro. The antibacterial activity of dicyclomine was confirmed by animal experiments. Toxicity and protective efficacy of the drug were tested in vivo.

RESULTS

Dicyclomine inhibited most of the bacterial isolates tested at 25-100 microg/ml concentration, and a few were sensitive even at a lower concentration (10 microg/ml). Dicyclomine was found to be bacteriostatic in nature against Shigella dysenteriae 7, and bactericidal against S. aureus NCTC 6571, 8530, and 8531. When administered to Swiss white mice at doses of 30 and 60 microg/mouse, dicyclomine protected the animals challenged with 50 MLD of Salmonella typhimurium NCTC 74.

INTERPRETATION & CONCLUSION

Dicyclomine showed inhibitory action against several pathogenic bacteria. It also offered significant protection to mice against the bacterial challange. As dicyclomine is in routine therapeutic use, it may be developed as a potent antimicrobial agent in many infections.

Evaluation of in vitro and in vivo antibacterial activity of dobutamine hydrochloride

PURPOSE

To determine the in vitro and in vivo antibacterial activity of a cardiovascular drug dobutamine hydrochloride.

METHODS

The minimum inhibitory concentration (MIC) of dobutamine was determined both by agar and broth dilution methods against 331 strains of bacteria from three gram positive and 13 gram negative genera. The antibacterial action of dobutamine was further tested in animal models.

RESULTS

Dobutamine was seen to possess powerful inhibitory action (5-200mg/mL) against most test bacteria in in vitro studies. It was bacteriostatic in nature. In vivo studies showed that the drug offered significant protection (p< 0.001) to mice challenged with a virulent bacterium.

CONCLUSION

Dobutamine showed remarkable antibacterial property against several pathogenic bacteria. Its potential as an antibacterial agent may be confirmed after further pharmacological studies.

Characterization of toxin from cheilanthes fern and its effect on lymphocyte proliferation and DNA fragmentation

Thin layer chromatography of aqueous extract of whole Cheilanthesfarinosa fern indicated the presence of ptaquiloside or ptaquiloside like compound, coinciding Rf values with that of Pterosin B standard. HPLC analysis revealed the presence of 26.3 mg/kg ptaquiloside. In vitro studies of the aqueous extract on lymphocyte culture revealed a correlation between stimulative indices and concentration of aqueous extract. Stimulation in lymphocyte proliferation was in order of bracken > cheilanthes > ConA> ptaquiloside standard. On incubation of lymphocyte with aqueous extract of ferns, no DNA damage was observed in isolated DNA.

The discovery of a potent, intracellular, orally bioavailable, long duration inhibitor of human neutrophil elastase--GW311616A a development candidate

The discovery of a potent intracellular inhibitor of human neutrophil elastase which is orally active and has a long duration of action is described. The pharmacodynamic and pharmacokinetic properties of a trans-lactam development candidate, GW311616A, are described.

A new phorbol diester from Aleurites moluccana

A new phorbol diester, 13-O-myristyl-20-O-acetyl-12-deoxyphorbol (1), has been isolated from the benzene extract of the heartwood of Aleurites moluccana. In addition, hentriacontane, 6,7-dimethoxycoumarin, 5,6,7-trimethoxycoumarin and beta-sitostenone are being reported for the first time from this species.

Intracellular inhibition of human neutrophil elastase by orally active pyrrolidine-trans-lactams

Described are the acylation binding of trans-lactam 1 to porcine pancreatic elastase, the selection of the SO2Me activating group for the lactam N which also confers metabolic stability in hamster liver microsomes, the introduction of aqueous solubility through the piperidine salt 9, the in vivo oral activity of 9 and its bioavailability, and the introduction of 9 as an intracellular neutrophil elastase inhibitor.

Solitary coherent structures in viscoelastic shear flow: computation and mechanism

Starting from stationary bifurcations in Couette-Dean flow, we compute nontrivial stationary solutions in inertialess viscoelastic circular Couette flow. These solutions are strongly localized vortex pairs, exist at arbitrarily large wavelengths, and show hysteresis in the Weissenberg number, similar to experimentally observed "diwhirl" patterns. Based on the computed velocity and stress fields, we elucidate a heuristic, fully nonlinear mechanism for these flows. We propose that these localized, fully nonlinear structures comprise fundamental building blocks for complex spatiotemporal dynamics in the flow of elastic liquids.

Dactuliophora Leaf Spot of Pearl Millet in Niger and Mali

Pearl millet (Pennisetum glaucum (L.) R. Br.) fields and cultivar trials in Sadoré, Niger, and Samanko, Mali, were surveyed in late August 1999 Most plants were in the late stem elongation to panicle exertion stage Local open-pollinated cultivars, experimental hybrids, and inbreds had disease severities of up to 10% of foliage diseased, with most severe disease on lower leaves. Individual, young, brown necrotic lesions averaged 2 × 1 mm and were surrounded by circular to irregular purple watersoaked margins 1 to 7 mm wide. Lesions expanded in irregular concentric rings, with zones of necrosis often separated by zones of green tissue Mature, individual lesions averaged 4.3 × 1.9 cm. Entire leaves could be blighted by coalescing lesions. No sclerotia were observed in young lesions, but sclerotia consistently developed and were macroscopically visible in necrotic tissues of older lesions. Sclerotia were oblong to pyriform (averaging 178 × 124 mm) and borne on erumpent, cup-shaped sclerotiophores. When incubated under high humidity, sterile gray mycelia grew rapidly from necrotic lesions up to a distance of ≈5 mm on the lower leaf surface, which likely resulted in the large concentric zones necrosis. Fungal characteristics and symptoms were consistent with disease caused by Dactuliophora elongata Leakey (1,2). Based on observations at the International Pearl Millet Downy Mildew Virulence Nursery in Mali, it is likely that resistance to D. elongata exists. Leaf spot of pearl millet caused by D. elongata has been reported only in Nigeria (1,2). Our observations confirm that the pathogen also is present on pearl millet Niger and Mali. References: (1) C. L. A. Leakey. Trans. Br. Mycol. Soc. 47:341, 1964. (2) P. D. Tyagi Proc. Ind. Acad. Sci. (Plant Sci.) 94:407, 1985.

Characterization of the DNA-binding domain of beta protein, a component of phage lambda red-pathway, by UV catalyzed cross-linking

beta protein, a key component of Red-pathway of phage lambda is necessary for its growth and general genetic recombination in recombination-deficient mutants of Escherichia coli. To facilitate studies on structure-function relationships, we overexpressed beta protein and purified it to homogeneity. A chemical cross-linking reagent, glutaraldehyde, was used to stabilize the physical association of beta protein in solution. A 67-kDa band, corresponding to homodimer, was identified after separation by SDS-polyacrylamide gel electrophoresis. Stoichiometric measurements indicated a site-size of 1 monomer of beta protein/5 nucleotide residues. Electrophoretic gel mobility shift assays suggested that beta protein formed stable nucleoprotein complexes with 36-mer, but not with 27- or 17-mer DNA. Interestingly, the interaction of beta protein with DNA and the stability of nucleoprotein complexes was dependent on the presence of MgCl2, and the binding was abolished by 250 mM NaCl. The Kd of beta protein binding to 36-mer DNA was on the order of 1.8 x 10(-6) M. Photochemical cross-linking of native beta protein or its fragments, generated by chymotrypsin, to 36-mer DNA was performed to identify its DNA-binding domain. Characterization of the cross-linked peptide disclosed that amino acids required for DNA-binding specificity resided within a 20-kDa peptide at the N-terminal end. These findings provide a basis for further understanding of the structure and function of beta protein.

Case report: renal scintigraphy in the diagnosis of urinary extravasation

Renal scintigraphy is a sensitive method for disclosing urinary extravasation. Its role following a road traffic accident is clearly presented in this case report. It is concluded that such a study can fill an important gap between the clinical and intravenous urography assessment and the more invasive studies in trauma victims.

DNA-induced conformational changes in RecA protein. Evidence for structural heterogeneity among nucleoprotein filaments and implications for homologous pairing

We have used circular dichroism as a probe to characterize the solution conformational changes in RecA protein upon binding to DNA. This approach revealed that RecA protein acquires significant amounts of alpha-helix upon interaction with DNA. These observations, consistent with the data from crystal structure (Story, R. M., Weber, I., and Steitz, T. (1992) Nature 355, 318-325), support the notion that some basic domains including the DNA binding motifs of RecA protein are unstructured and might contribute to the formation of alpha-helix. A comparison of nucleoprotein filaments comprised of RecA protein and a variety of DNA substrates revealed important structural heterogeneity. The most significant difference was observed with poly(dG). poly(dC) and related polymers, rich in GC sequences, which induced minimal amounts of alpha-helix in RecA protein. The magnitude of induction of alpha-helix in RecA protein, which occurred concomitant with the production of ternary complexes, was 2-fold higher with homologous than heterologous duplex DNA. Most importantly, the stimulation of ATP hydrolysis by high salt coincided with that of the induction of alpha-helix in RecA protein. These conformational differences provide a basis for thinking about the biochemical and structural transitions that RecA protein experiences during the formal steps of presynapsis, recognition, and alignment of homologous sequences.

Use of structure-directed DNA ligands to probe the binding of recA protein to narrow and wide grooves of DNA and on its ability to promote homologous pairing

We have used circular dichroism and structure-directed drugs to identify the role of structural features, wide and narrow grooves in particular, required for the cooperative polymerization, recognition of homologous sequences, and the formation of joint molecules promoted by recA protein. The path of cooperative polymerization of recA protein was deduced by its ability to cause quantitative displacement of distamycin from the narrow groove of duplex DNA. By contrast, methyl green bound to the wide groove was retained by the nucleoprotein filaments comprised of recA protein-DNA. Further, the mode of binding of these ligands and recA protein to DNA was confirmed by DNaseI digestion. More importantly, the formation of joint molecules was prevented by distamycin in the narrow groove while methyl green in the wide groove had no adverse effect. Intriguingly, distamycin interfered with the production of coaggregates between nucleoprotein filaments of recA protein-M13 ssDNA and naked linear M13 duplex DNA, but not with linear phi X174 duplex DNA. Thus, these data, in conjunction with molecular modeling, suggest that the narrow grooves of duplex DNA provide the fundamental framework required for the cooperative polymerization of recA protein and alignment of homologous sequences. These findings and their significance are discussed in relation to models of homologous pairing between two intertwined DNA molecules.

Idiopathic hypereosinophilic syndrome presenting as childhood hemiplegia

A case of childhood hemiplegia due to idiopathic hypereosinophilic syndrome is reported. There was no cardiac lesion. The neurological complications associated with hypereosinophilic syndrome and the pathophysiological mechanism of neurotoxicity of human eosinophils are discussed. It is likely that the neurological deficit was due to eosinophilic neurotoxicity.

Haemodialysis-related porphyria cutanea tarda and treatment by recombinant human erythropoietin

Haemodialysis-related porphyria cutanea tarda is a rare, but serious and mutilating skin condition, resulting from extremely high plasma porphyrin levels because of their inadequate clearance by haemodialysis. The treatment is very difficult as chloroquine is ineffective and venesection, the conventional treatment of this disease, is not always an option because of anaemia of end-stage renal disease. We report a case of haemodialysis-related porphyria cutanea tarda and her successful management by recombinant human erythropoietin treatment.

Clinico-pathological profile of lymphomas in south India: a prospective rural referral hospital study of 103 cases

A prospective clinical and histopathological study of 103 patients with lymphomas is reported. Of these, 72 (69.9%) had non-Hodgkin's lymphoma (NHL) and 31 (30.1%) had Hodgkin's lymphoma (HL). The median age at presentation was 34 and 43 years for Hodgkin's and non-Hodgkin's lymphoma respectively, which is lower than that seen in the West. Fever and superficial lymphadenopathy were the commonest presenting features and 'B' symptoms were present in over 60% of both groups. Seventy-five per cent of NHL and 64.5% of HL presented in stages III and IV of the disease.

A microcomputer program to analyze the CD spectrum of proteins and nucleic acids--use of LOTUS 1-2-3 spread sheet

A user friendly interactive computer program, CIRDIC, is developed which calculates the molar ellipticity and molar circular dichroic absorption coefficients from the CD spectrum. This, in combination with LOTUS 1-2-3 spread sheet, will give the spectra of above parameters vs wavelength. The code is implemented in MicroSoft FORTRAN 77 which runs on any IBM compatible PC under MSDOS environment.