Results of the Dutch National study of the palliative effect of irradiation using two different treatment schemes for non-small-cell lung cancer.

PURPOSE: A national multicenter randomized study compared the efficacy of 2 x 8 Gy versus our standard 10 x 3 Gy in patients with inoperable stage IIIA/B (with an Eastern Cooperative Oncology Group score of 3 to 4 and/or substantial weight loss) and stage IV non-small-cell lung cancer. PATIENTS AND METHODS: Between January 1999 and June 2002, 297 patients were eligible and randomized to receive either 10 x 3 Gy or 2 x 8 Gy by external-beam irradiation. The primary end point was a patient-assessed score of treatment effect on seven thoracic symptoms using an adapted Rotterdam Symptom Checklist. Study sample size was determined based on an average total symptom score difference of more than one point over the initial 39 weeks post-treatment. The time course of symptom scores were also evaluated, and other secondary end points were toxicity and survival. RESULTS: Both treatment arms were equally effective, as the average total symptom score over the initial 39 weeks did not differ. However, the pattern in time of these scores differed significantly (P < .001). Palliation in the 10 x 3-Gy arm was more prolonged (until week 22) with less worsening symptoms than in 2 x 8-Gy. Survival in the 10 x 3-Gy arm was significantly (P = .03) better than in the 2 x 8-Gy arm with 1-year survival of 19.6% (95%CI, 14.1% to 27.3%) v 10.9% (95%CI, 6.9% to 17.3%). CONCLUSION: The 10 x 3-Gy radiotherapy schedule is preferred over the 2 x 8-Gy schedule for palliative treatment, as it improves survival and results in a longer duration of the palliative response.

Semiempirical Quantum-Chemical Orthogonalization-Corrected Methods: Theory, Implementation, and Parameters.

Semiempirical orthogonalization-corrected methods (OM1, OM2, and OM3) go beyond the standard MNDO model by explicitly including additional interactions into the Fock matrix in an approximate manner (Pauli repulsion, penetration effects, and core-valence interactions), which yields systematic improvements both for ground-state and excited-state properties. In this Article, we describe the underlying theoretical formalism of the OMx methods and their implementation in full detail, and we report all relevant OMx parameters for hydrogen, carbon, nitrogen, oxygen, and fluorine. For a standard set of mostly organic molecules commonly used in semiempirical method development, the OMx results are found to be superior to those from standard MNDO-type methods. Parametrized Grimme-type dispersion corrections can be added to OM2 and OM3 energies to provide a realistic treatment of noncovalent interaction energies, as demonstrated for the complexes in the S22 and S66×8 test sets.

Looking at self-consistent-charge density functional tight binding from a semiempirical perspective.

The self-consistent-charge density functional tight binding (SCC-DFTB) method is compared with other semiempirical methods (MNDO, AM1, PM3, OM1, OM2, OM3). Despite the differences in the underlying philosophy and derivation, these methods share many common features. Systematic evaluations of their performance are reported for standard test sets that are in common use. The overall accuracy of SCC-DFTB and the other methods is in the same range, with the overall tendency AM1