The International Lymphoma Radiation Oncology Group presents a standardized approach to the use and implementation of definitive RT in solitary plasmacytomas. The modern principles outlining the supportive role of palliative RT in multiple myeloma in an era of novel systemic therapies are also discussed.

BACKGROUND: This study was conducted to evaluate the long-term outcomes in patients with stage IE and IIE mucosa-associated lymphoid tissue (MALT) lymphomas treated with involved field radiotherapy (RT). METHODS: Between 1989 and 2004, 192 patients with stage I and II MALT lymphomas were treated. The report focuses on 167 patients who received RT. The median age of patients was 58 years with a female predominance (2:1). Presenting sites were as follows: orbital adnexa in 71 patients, salivary glands in 28 patients, stomach in 25 patients, thyroid in 21 patients, and other sites in 22 patients. The median dose to nonorbital sites was 30 grays (Gy) (range, 17.5-35 Gy) and was 25 Gy for the orbit (range, 25-35 Gy). The median follow-up was 7.4 years (range, 0.67-16.20 years). RESULTS: Complete response and complete response, unconfirmed (CR/CRu) was noted in 166 (99%) patients. The 10-year recurrence-free rate (RFR) was 76%, the disease-free survival (DFS) rate was 68%, the overall survival (OS) rate was 87%, and the cause-specific survival rate was 98%. According to presenting site, the 10-year RFR was 95% for thyroid, 92% for stomach, 68% for salivary glands, and 67% for orbit. Patients with thyroid and gastric MALTs had better outcome compared with patients with MALTs diagnosed at other sites (P ¼.004). Among those patients who achieved CR, 19% developed disease recurrence (n ¼ 31), chiefly in distant sites or untreated contralateral-paired organs. At the time of disease recurrence, 7 patients (23%) had transformed to diffuse large B-cell lymphoma, 2 of whom died of lymphoma. The 5-year OS rate after treatment failure was 83%. CONCLUSIONS: Patients with localized MALT lymphomas are reported to have excellent clinical outcome after moderate-dose RT, and some are likely cured. In the current study, thyroid and gastric MALTs were found to have significantly less risk of distant recurrence. Despite disease recurrence, the overall survival remains excellent in these patients. Cancer 2010;116:3815-24.

No abstract

Understanding of molecular events underlying resistance and relapse in glioblastoma (GBM) is hampered due to lack of accessibility to resistant cells from patients undergone therapy. Therefore, we mimicked clinical scenario in an in vitro cellular model developed from five GBM grade IV primary patient samples and two cell lines. We show that upon exposure to lethal dose of radiation, a subpopulation of GBM cells, innately resistant to radiation, survive and transiently arrest in G2/M phase via inhibitory pCdk1(Y15). Although arrested, these cells show multinucleated and giant cell phenotype (MNGC). Significantly, we demonstrate that these MNGCs are not pre-existing giant cells from parent population but formed via radiation-induced homotypic cell fusions among resistant cells. Furthermore, cell fusions induce senescence, high expression of senescence-associated secretory proteins (SASPs) and activation of pro-survival signals (pAKT, BIRC3 and Bcl-xL) in MNGCs. Importantly, following transient non-proliferation, MNGCs escape senescence and despite having multiple spindle poles during mitosis, they overcome mitotic catastrophe to undergo normal cytokinesis forming mononucleated relapse population. This is the first report showing radiation-induced homotypic cell fusions as novel non-genetic mechanism in radiation-resistant cells to sustain survival. These data also underscore the importance of non-proliferative phase in resistant glioma cells. Accordingly, we show that pushing resistant cells into premature mitosis by Wee1 kinase inhibitor prevents pCdk1(Y15)-mediated cell cycle arrest and relapse. Taken together, our data provide novel molecular insights into a multistep process of radiation survival and relapse in GBM that can be exploited for therapeutic interventions.

Approximately 30% to 40% of patients with diffuse large B-cell lymphoma (DLBCL) will have either primary refractory disease or relapse after chemotherapy. In transplant-eligible patients, those with disease sensitive to salvage chemotherapy will significantly benefit from high-dose therapy with autologous stem cell transplantation. The rationale for considering radiation therapy (RT) for selected patients with relapsed/refractory DLBCL as a part of the salvage program is based on data regarding the patterns of relapse and retrospective series showing improved local control and clinical outcomes for patients who received peritransplant RT. In transplant-ineligible patients, RT can provide effective palliation and, in selected cases, be administered with curative intent if the relapsed/refractory disease is localized. We have reviewed the indications for RT in the setting of relapsed/refractory DLBCL and provided recommendations regarding the optimal timing of RT, dose fractionation scheme, and treatment volume in the context of specific case scenarios.

The development of effective therapeutic strategies for glioblastoma faces challenges such as modulating the blood brain barrier (BBB) for drug influx and selectively targeting tumor cells. Nanocarrier drug delivery strategies are functionalized to enhance vascular permeability. We engineered superparamagnetic iron oxide nanoparticle (SPION) based polymeric nanocomposites (84.37 ± 12.37 nm / 101.56 ± 7.42 nm) embedding temozolomide (TMZ) targeted against glioblastoma by tagging an antibody against nestin, a stem cell marker, and transferrin / polysorbate-80 to permeate the BBB. The targeting and therapeutic efficacy of the nanocomposite resulted in enhanced permeability across the BBB in an orthotopic glioblastoma xenograft model. Sustained release of TMZ from the nanocomposite contributed to enhanced tumor cell death while sparing normal brain cells as evidenced through micro SPECT/CT analysis. The functionalized nanocomposites showed significant reductions in tumor volume compared to pure TMZ, as substantiated by reduced proliferation markers such as proliferating cell nuclear antigen (PCNA) and Ki-67. We report here a novel targeted TMZ delivery strategy using a potent homing moiety, nestin, tagged to a polymeric nanocomposite to target glioblastoma. In addition to tumor targeting, this study constitutes a broad horizon for enhanced therapeutic efficacy with further scope for capitalizing on the magnetic properties of SPION for targeted killing of cancer cells while sparing normal tissues.

No abstract

No abstract