Stereotactic radiotherapy in targeted therapy treated oligo-metastatic oncogene-addicted (non-small-cell) lung cancer.

While the prognosis of metastatic non-small-cell lung cancer has shown significant progress these last years, notably with the discovery of oncogen-driven subtypes and the development of targeted therapies, significant improvements are still needed. More recently, numerous authors studied the oligo-metastasis concept, where the metastasis are limited in number and sites involved, and that could benefit from an aggressive approach of these lesions, for instance with the help of stereotactic radiotherapy. Nevertheless, there is no clear consensus existing for the time being for the treatment of these tumors. Three main clinical situations can be distinguished: oligo-metastasis state de novo at diagnosis (synchronous) or as first metastatic event of an initially locally limited affection (metachronous); oligo-progression during systemic treatment of a pluri-metastatic disease; and finally oligo-persistence of some remaining metastatic lesions at the nadir of the systemic therapy effect. In this review, we will discuss the place of stereotactic radiotherapy in the treatment of non-small-cell oligo-metastatic oncogene-addicted cancers treated with targeted therapies, differentiating these three main clinical situations. In all these indications, this technique could provide a benefit in terms of local control, possibly even in specific survival, when associated with targeted therapy continuation, related to local control of the oligo-metastatic cerebral or extracerebral lesions.

Multicenter observational study of erlotinib therapy (OBSTAR) for non small-cell lung cancer: a GFPC study.

CONTEXT: Erlotinib therapy for non small-cell lung cancer (NSCLC) has mainly been evaluated in randomized trials. METHOD: OBSTAR was a multicenter, retrospective, observational study involving all patients treated with erlotinib in 18 French centers between June 2005 and September 2007. The analyses focused on the patients' characteristics, previous treatments, and treatment efficacy during a three-year follow-up period. RESULTS: 534 patients were included in this study. The median survival times were respectively 5.2 [3.7-7.4] and 4.7 [4.1-5.7] months, depending to whether erlotinib was used as second- (n=190), or ≥ third-line treatment (n=305). The disease control rate were 39.1% [30.2-48.7] and 29.9% [29.6-36.9] according to the line of treatment. Factors predictive of an objective response were gender, age, and smoking status. Factors predictive of progression were age, sex, smoking status, the line of treatment, and the number of metastases. Treatment had to be interrupted for toxicity in 8.5% of cases. CONCLUSION: This study of erlotinib therapy in 2005-2007 confirms, in the general NSCLC patient population, the results of pivotal trials.

[Routine use of electronic portal imaging. Positioning verification in 922 successive pelvic fields]. / Utilisation en routine du portal imaging électronique. Vérification de mise en place de 922 champs pelviens successifs.

Treatment reproducibility is a major criterion of quality assurance in radiation therapy. During each course, the same dose should be delivered in the same volume of irradiation. Today, portal imaging devices can be used routinely to check and correct patient positioning before much of the daily irradiation has been delivered. In this study we used the Portal Vision Varian (PVV) system during pelvic irradiation in 16 patients. This device can automatically acquire portal images in the first seconds of each course. Observed discrepancies are directly classified by the radiation oncologist according to their type (cranio-caudal, lateral, antero-posterior) and severity (correction of patient positioning is necessary or not). In case of error, patient positioning is corrected before the end of irradiation. Of the 922 portals analysed with PVV, 901 could be analysed (97%). Two hundred and ninety-nine positioning discrepancies were observed (33%) with 59 of them leading to correction (6%). Most of the time, these errors concerned antero-posterior portals. Finally, each patient had an average of 18 to 19 discrepancies which were mainly of no importance for treatment quality. Nevertheless, real errors leading to correction were observed in 14 patients (88%) with an average of four per patient. In some patients many errors occurred, while in others only a few. These shifts were not related to patient weight and thickness but probably a portal dimension. In summary, we think that during pelvic irradiation a portal imaging device should be used daily to improve treatment quality. This system can help the radiation oncologist to discover many positioning errors (an average of four) in the majority of patients (88%) and to correct them before the end of irradiation.