Primary Radiation (primary + radiation)

Distribution by Scientific Domains


Selected Abstracts


Salvage treatment for persistent and recurrent T1,2 nasopharyngeal carcinoma by stereotactic radiosurgery

HEAD & NECK: JOURNAL FOR THE SCIENCES & SPECIALTIES OF THE HEAD AND NECK, Issue 9 2001
Daniel T. T. Chua FRCR
Abstract Objective To study the efficacy of stereotactic radiosurgery in salvaging early-stage persistent and recurrent nasopharyngeal carcinoma (NPC) after primary radiotherapy. Methods A prospective single-arm study evaluating the response and outcome of patients with rT1,2 NPC treated by stereotactic radiosurgery. Eleven patients with rT1,2 were treated by radiosurgery between March 1998 and March 2000. Four patients were treated for persistent disease occurring within 4 months after primary radiotherapy, six were treated for first recurrence, and one for third recurrence. Six patients had rT1 disease and five had rT2 disease. Most patients had disease not amenable to brachytherapy, surgery, or external re-irradiation. The median target volume was 5.8 cc (range, 3.3,16.9). Radiosurgery was performed with multiple noncoplanar arcs of photon, with a median dose of 12.5 Gy delivered to the 80% isodose line (range, 12,14 Gy). Median follow-up time after radiosurgery was 18 months (range, 9,30). Results Nine patients had complete regression of tumor as assessed by imaging, nasopharyngoscopy, and biopsy; one patient had partial regression of tumor; whereas one patient had static disease. The overall response rate was 91% (10 of 11) and the complete response rate was 82% (9 of 11). Two patients with complete response subsequently had local relapse develop, with one recurrence outside the treated volume 8 months after radiosurgery, and the other within the treated volume 6 months after radiosurgery. One patient with a partial response had neck node recurrence develop. Temporal lobe necrosis occurred in one patient but probably represents sequelae of primary radiation after reviewing the dosimetry. Ten patients are still alive, whereas one patient with local relapse had distant metastases develop and died. The estimated 1-year local control rate after radiosurgery was 82%. Conclusions Our preliminary results indicate that stereotactic radiosurgery is an effective treatment modality for persistent and recurrent T1,T2 NPC, and early control rate seems to be comparable to other salvage treatments. More clinical experiences and longer follow-up are still needed to validate our results and to address fully the role of radiosurgery in salvaging local failures of NPC. © 2001 John Wiley & Sons, Inc. Head Neck 23: 791,798, 2001. [source]


Diversity patterns amongst herbivorous dinosaurs and plants during the Cretaceous: implications for hypotheses of dinosaur/angiosperm co-evolution

JOURNAL OF EVOLUTIONARY BIOLOGY, Issue 3 2009
R. J. BUTLER
Abstract Palaeobiologists frequently attempt to identify examples of co-evolutionary interactions over extended geological timescales. These hypotheses are often intuitively appealing, as co-evolution is so prevalent in extant ecosystems, and are easy to formulate; however, they are much more difficult to test than their modern analogues. Among the more intriguing deep time co-evolutionary scenarios are those that relate changes in Cretaceous dinosaur faunas to the primary radiation of flowering plants. Demonstration of temporal congruence between the diversifications of co-evolving groups is necessary to establish whether co-evolution could have occurred in such cases, but is insufficient to prove whether it actually did take place. Diversity patterns do, however, provide a means for falsifying such hypotheses. We have compiled a new database of Cretaceous dinosaur and plant distributions from information in the primary literature. This is used as the basis for plotting taxonomic diversity and occurrence curves for herbivorous dinosaurs (Sauropodomorpha, Stegosauria, Ankylosauria, Ornithopoda, Ceratopsia, Pachycephalosauria and herbivorous theropods) and major groups of plants (angiosperms, Bennettitales, cycads, cycadophytes, conifers, Filicales and Ginkgoales) that co-occur in dinosaur-bearing formations. Pairwise statistical comparisons were made between various floral and faunal groups to test for any significant similarities in the shapes of their diversity curves through time. We show that, with one possible exception, diversity patterns for major groups of herbivorous dinosaurs are not positively correlated with angiosperm diversity. In other words, at the level of major clades, there is no support for any diffuse co-evolutionary relationship between herbivorous dinosaurs and flowering plants. The diversification of Late Cretaceous pachycephalosaurs (excluding the problematic taxon Stenopelix) shows a positive correlation, but this might be spuriously related to poor sampling in the Turonian,Santonian interval. Stegosauria shows a significant negative correlation with flowering plants and a significant positive correlation with the nonflowering cycadophytes (cycads, Bennettitales). This interesting pattern is worthy of further investigation, and it reflects the decline of both stegosaurs and cycadophytes during the Early Cretaceous. [source]


Planned Postradiotherapy Neck Dissection: Rationale and Clinical Outcomes

THE LARYNGOSCOPE, Issue 1 2007
Gregory K. Sewall MD
Abstract Objectives: In this study, we examine pathology results and clinical outcome for patients with locoregionally advanced squamous cell carcinoma of the head and neck (SCCHN) who present with advanced neck disease and undergo planned postradiotherapy neck dissection. Study Design: Review of all patients with SCCHN treated with primary radiation (or chemoradiation) and postradiotherapy neck dissection at the University of Wisconsin between 1992 to 2005 was performed. One hundred seven neck dissections were identified in 93 patients, 79 unilateral and 14 bilateral. All major treatment and outcome parameters were examined with particular emphasis on the postradiotherapy neck dissection. Results: Thirty of 107 neck dissection specimens (28%) showed evidence of residual carcinoma on pathologic review. The mean number of lymph nodes identified at neck dissection for the entire cohort was 21 per specimen (range, 1,60) with 1.3 nodes per positive neck dissection demonstrating residual carcinoma. No correlation was found between the type of neck dissection performed and the presence of residual nodal disease. Eighty-two evaluated patients (93%) remain free of regional disease recurrence, whereas six patients have subsequently manifested neck recurrence. Four of the six patients who developed regional recurrence showed residual carcinoma in their neck dissection specimen. Five of these patients underwent comprehensive neck dissection (levels I,V); one underwent selective neck dissection ([source]


4364: Direct intra-arterial (ophthalmic artery) chemotherapy with melphalan for advanced intraocular retinoblastoma: the Italian experience

ACTA OPHTHALMOLOGICA, Issue 2010
T HADJISTILIANOU
Purpose To report the preliminary results of the conservative treatment of advanced retinoblastoma (Stage Va e Vb) obtained with the melphalan protocol (direct intraarterial-ophthalmic artery infusion ). Methods 33 children (35 eyes) with advanced retinoblastoma who were eligible for enucleation were entered in phase two of one center open study-approved protocol of ophthalmic artery infusion of Melphalan to avoid enucleation (Italian Melphalan protocol, approved by the Ethic Commettee , University Hospital of Siena). Two cases have been treated bilaterally. 15 eyes were first diagnosis and 18 were relapses following chemo and/or radiotherapy. In two cases has not been possible to conclude the procedure due to haemodynamic problems. Results The ophthalmic artery was successfully cannulated in 35 eyes (total, 121 procedures). In 2 attempts was impossible to successfully conclude the procedure due to hemodynamic problems. Cannulation of the ophthalmic artery was performed by a femoral artery approach using microcatheters (magic 1.5) while the children were under general anesthesia and anticoagulated. Melphalan was infused into the artery over a 30-minute period (dose of 3-7 mg according to the age and size of the globe). Local and systemic toxicity have been evaluated and documented. Conclusion 33 children (35 eyes) with advanced retinoblastoma (Stage Va and Vb Reese classification) were eligible for the Melphalan Italian Protocol. The 78.7% of treated eyes is in complete remission. Superselective chemotherapy delivered through the ophthalmic artery can avoid enucleation, primary radiation or abuse of systemic chemotherapy. [source]