Building Social Capital Through Microfinance

A number of development assistance programs promote community interaction as a means of building social capital. Yet, despite strong theoretical underpinnings, the role of repeat interactions in sustaining cooperation has proven difficult to identify empirically. We provide the first experimental evidence on the economic returns to social interaction in the context of microfinance. Random variation in the frequency of mandatory meetings across first-time borrower groups generates exogenous and persistent changes in clients' social ties. We show that the resulting increases in social interaction among clients more than a year later are associated with improvements in informal risk-sharing and reductions in default. A second field experiment among a subset of clients provides direct evidence that more frequent interaction increases economic cooperation among clients. Our results indicate that group lending is successful in achieving low rates of default without collateral not only because it harnesses existing social capital, as has been emphasized in the literature, but also because it builds new social capital among participants

Building Social Capital Through MicroFinance

A number of development assistance programs promote community interaction as a means of building social capital. Yet, despite strong theoretical underpinnings, the role of repeat interactions in sustaining cooperation has proven difficult to identify empirically. We provide the first experimental evidence on the economic returns to social interaction in the context of microfinance. Random variation in the frequency of mandatory meetings across first-time borrower groups generates exogenous and persistent changes in clients' social ties. We show that the resulting increases in social interaction among clients more than a year later are associated with improvements in informal risk-sharing and reductions in default. A second field experiment among a subset of clients provides direct evidence that more frequent interaction increases economic cooperation among clients. Our results indicate that group lending is successful in achieving low rates of default without collateral not only because it harnesses existing social capital, as has been emphasized in the literature, but also because it builds new social capital among participants.

Complete Pathologic Response Following Multimodality Therapy for a Recurrent, High-Grade Phyllodes Tumor

Introduction: Phyllodes tumor is a rare mesenchymal tumor of the breast for which surgical resection is the primary therapy. Despite adequate surgical resection, local recurrence rates of up to 40% are observed in patients with high-grade tumors. The role of adjuvant radiation therapy and chemotherapy for phyllodes tumor to improve local and systemic control is not well established. However, several small studies have shown improvements in local control rates with adjuvant radiation therapy. The management of aggressive local phyllodes tumor recurrences can be a clinical challenge and multimodality therapy should be considered in these cases for optimal results.Case presentation: We present the case of a high-grade phyllodes tumor that recurred in the radiation field after adjuvant radiation therapy. The patient was treated with neoadjuvant hyperfractionated, accelerated radiotherapy in combination with hyperthermia and chemotherapy followed by radical surgical resection. A completed pathologic response was observed.Conclusion: This multimodality approach may be a successful treatment algorithm for high-grade tumors that reoccur in a prior radiation field

Sustained Immune Tolerance Induction in Enzyme Replacement Therapy-Treated CRIM-Negative Patients with Infantile Pompe Disease

BACKGROUND: Cross-reactive immunological material-negative (CRIM-negative) infantile Pompe disease (IPD) patients develop an immune response against enzyme replacement therapy (ERT) with alglucosidase alfa that nullifies ERT efficacy. Prophylactic immune tolerance induction (ITI) with rituximab, methotrexate, and IVIG successfully prevents development of deleterious rhGAA IgG antibodies; however, safety, likelihood of success, and long-term efficacy of ITI in a larger cohort remain unknown. METHODS: Clinical data were analyzed for 19 CRIM-negative IPD patients who received ITI with rituximab, methotrexate, and IVIG in the ERT-naive setting (ERT+ITI) and compared to a historical cohort of 10 CRIM-negative IPD patients on ERT monotherapy. RESULTS: ITI was safely tolerated, although infections were reported in 4 patients. Fourteen (74%) ERT+ITI patients were alive, with a median age of 44.2 months at their final assessment. The eldest survivor was 103.9 months old, with 100.2 months of follow-up after initiation of ERT+ITI. Death (n = 5) occurred at a median age of 29.2 months and was unrelated to the administration of ITI. Fifteen patients either did not seroconvert (n = 8) or maintained low titers (n = 7; defined as titers of /=51,200 at or beyond 6 months on ERT). Left ventricular mass index (LVMI) decreased from a median of 248.5 g/m2 at baseline to 76.8 g/m2 at a median time from ERT+ITI initiation to 59 weeks. ERT+ITI significantly improved overall survival (P = 0.001), eliminated/reduced antibodies at values o

Updating Photon-Based Normal Tissue Complication Probability Models for Pneumonitis in Patients With Lung Cancer Treated With Proton Beam Therapy

Purpose: No validated models for predicting the risk of radiation pneumonitis (RP) with proton beam therapy (PBT) currently exist. Our goal was to externally validate and recalibrate multiple established photon-based normal tissue complication probability models for RP in a cohort with locally advanced nonsmall cell lung cancer treated with contemporary doses of chemoradiation using PBT. Methods and Materials: The external validation cohort consisted of 99 consecutive patients with locally advanced nonsmall cell lung cancer treated with chemoradiation using PBT. RP was retrospectively scored at 3 and 6 months posttreatment. We evaluated the performance of the photon Quantitative Analyses of Normal Tissue Effects in the Clinic (QUANTEC) pneumonitis model, the QUANTEC model adjusted for clinical risk factors, and the newer Netherlands updated QUANTEC model. A closed testing procedure was performed to test the need for model updating, either by recalibration-in-the-large (re-estimation of intercept), recalibration (re-estimation of intercept/slope), or model revision (re-estimation of all coefficients). Results: There were 21 events (21%) of ≥grade 2 RP. The closed testing procedure on the PBT data set did not detect major deviations between the models and the data and recommended adjustment of the intercept only for the photon-based Netherlands updated QUANTEC model (intercept update: –1.2). However, an update of the slope and revision of the model coefficients were not recommended by the closed testing procedure, as the deviations were not significant within the power of the data. Conclusions: The similarity between the dose-response relationship for PBT and photons for normal tissue complications has been an assumption until now. We demonstrate that the preexisting, widely used photon based models fit our PBT data well with minor modifications. These now-validated and updated normal tissue complication probability models can aid in individualizing selection of the most optimal treatment technique for a particular patient

An investigation of intensity-modulated radiation therapy versus conventional two-dimensional and 3D-conformal radiation therapy for early stage larynx cancer

<p>Abstract</p> <p>Introduction</p> <p>Intensity modulated radiation therapy (IMRT) has been incorporated at several institutions for early stage laryngeal cancer (T1/T2N0M0), but its utility is controversial.</p> <p>Methods</p> <p>In three representative patients, multiple plans were generated: 1) Conventional 2D planning, with the posterior border placed at either the anterior aspect ("tight" plan) or the mid-vertebral body ("loose" plan), 2) 3D planning, utilizing both 1.0 and 0.5 cm margins for the planning target volume (PTV), and 3) IMRT planning, utilizing the same margins as the 3D plans. A dosimetric comparison was performed for the target volume, spinal cord, arytenoids, and carotid arteries. The prescription dose was 6300 cGy (225 cGy fractions), and the 3D and IMRT plans were normalized to this dose.</p> <p>Results</p> <p>For PTV margins of 1.0 cm and 0.5 cm, the D95 of the 2D tight/loose plans were 3781/5437 cGy and 5372/5869 cGy, respectively (IMRT/3D plans both 6300 cGy). With a PTV margin of 1.0 cm, the mean carotid artery dose was 2483/5671/5777/4049 cGy in the 2D tight, 2D loose, 3D, and IMRT plans, respectively. When the PTV was reduced to 0.5 cm, the the mean carotid artery dose was 2483/5671/6466/2577 cGy to the above four plans, respectively. The arytenoid doses were similar between the four plans, and spinal cord doses were well below tolerance.</p> <p>Conclusions</p> <p>IMRT provides a more ideal dose distribution compared to 2D treatment and 3D planning in regards to mean carotid dose. We therefore recommend IMRT in select cases when the treating physician is confident with the GTV.</p

Outcome of Patients with Localized Prostate Cancer Treated by Radiotherapy After Confirming the Absence of Lymph Node Invasion

doi:10.1093/jjco/hyq03