Results of a prospective randomised trial comparing conventional radiotherapy to split course bifractionated radiation therapy in patients with nasopharyngeal carcinoma.

BACKGROUND AND PURPOSE: Nasopharyngeal carcinoma (NPC) is generally responsive to radiation therapy. However therapeutic results after conventional radiotherapy remain relatively poor especially for patients with locoregional advanced NPC. The aim of this study was to evaluate the impact of a split course bifractionated radiotherapy regimen in a phase III randomised trial. PATIENTS AND METHODS: From January 1997 to September 2003, 154 patients with M0 histologically proven NPC were treated in our institution. They were staged according to the American Joint Committee on Cancer - International Union Against Cancer (AJCC-UICC) 1986 TNM classification. Patients with locally advanced nodal disease (N2-N3) received induction chemotherapy. All patients were randomised to receive either conventional radiotherapy at 2 Gy/fraction/day, 5 days/week to 70 Gy/7 weeks or split course bifractionated radiotherapy at 1.6 Gy/fraction, twice daily, 5 days/week to 70.4 Gy/6 weeks. Response and toxicity were evaluated according to the WHO and RTOG criteria. RESULTS: Patients were well balanced between the two arms. The complete remission rate was 91% in conventional radiotherapy arm and 93% in bifractionated radiotherapy arm (p=0.3). There was more grade II-III skin fibrosis in experimental arm with a 5 year actuarial probability of 66% vs 52% (p=0.04). Locoregional and distant relapses occurred in 34% of cases in conventional arm and 38% in experimental arm (p=0.28). With a median follow-up of 56 months, the 5 year overall survival and the disease free survival rates were, respectively (71% and 61%), in conventional arm and (62% and 60%) in bifractionated arm, the difference being statistically non significant. COMMENTS: The present trial comparing conventional radiotherapy to a split course bifractionated radiation therapy failed to demonstrate significant improvement in locoregional control and survival in experimental arm which was associated with more grade II-III skin fibrosis.     

A proposal for MRI-based parcellation of the frontal pole

The frontal pole (FP), which largely overlaps with Brodmann’s area (BA) 10, is the rostral-most part of the hominid cerebral cortex, and plays a critical role in complex aspects of human cognition. The existing conventions suggested for MRI-based parcellation of this important frontal subdivision have limited cytoarchitectonic meaning with regard to the demarcation of the FP from adjacent prefrontal subdivisions. In this paper, we propose the coronal section containing the anterior termination of the olfactory sulcus (ATOS) as an easy-to-identify landmark for FP parcellation that largely overlaps with the cytoarchitectonic distinction between BA 10 and the more posterior cytoarchitectonic subdivisions of the PFC. Manual segmentation-based parcellation of the FP using the proposed landmark in 20 healthy volunteers yielded highly reliable (standardized item alpha = 0.92) volumetric estimates [right FP volume = 8.421 cm³ (SE = 0.773, range 3.107–15.741); left FP volume = 8.039 cm³ (SE = 0.708, range 2.234–12.956)]. The volumetric measurements of right FP generated in the present study were comparable to those reported in a prior study of BA 10 using histological sections and stereological techniques (Semendeferi et al. In: Am J Phys Anthropol 114:224–241, 2001). Therefore, in the absence of a naturally occurring sulcal boundary, the proposed method for parcellation of the FP can provide unbiased volume estimations for studies of healthy and disordered populations of subjects.