In 1st-line trials, the relative Progression Free Survival (PFS) benefit of adding CDK4/6 inhibitors to AI was consistent across all subgroups of patients (pts), including those with lower ER expression. However, little is known about the absolute PFS obtained under CDK4/6i and AI in pts with low ER expression and whether PR and HER2 expression impact PFS in this setting. PADA-1 is a phase III trial (NCT03079011) testing the clinical utility of ESR1mut detection in blood in ER ≥ 10% HER2- MBC pts receiving 1st- line Pal + AI. We investigated the association of locally-assessed ER (%), PR (%) and HER2 (0,1+,2+) IHC expression on the most recent tumor sample with PFS under Pal + AI. Of 1017 pts, 12 (1.2%), 34 (3.5%), 181 (18.5%) & 751 (76.8%) had an ER% expression of [10-20%], [21-50%], [51-80%] & [81-100%], respectively. N=249 pts (29.2%), 148 (17.3%), 186 (21.8%) & 270 (31.6%) had a PR% of [0-20%], [21-50%], [51-80%] & [81-100%], respectively (Allred scores will be presented). Available HER2 IHC scores were 0 & 1+/2+ in 357 (54.6%) & 296 (45.4%) pts, respectively. In univariate analysis, after a mFU of 28.1 months and 527 PFS events (51.8%) under Pal + AI, mPFS in pts with [10-50%], [51-80%] & [81-100%] ER IHC were 14.1, 21.6 & 30.1 months, respectively. mPFS in pts with [0-50%], [51-80%] & [81-100%] PR IHC were 20.6, 27.1 and 42.6 months, respectively. Longer PFS were observed in HER2(1/2+) vs (0) MBC (HR=0.79 [0.64;0.98]). In multivariate analysis, aside standard prognostic factors (PS, age, visceral disease, number of metastatic site, DMFI), both ER% and PR% had an independent prognostic impact: each +10% gain in ER% was associated with a reduced 10% risk of PFS event under Pal + AI (HR=0.90, 95%CI [0.84;0.96], p=0.002); each +10% gain in PR% was associated with a reduced 8% risk of PFS event under Pal + AI (HR=0.92, 95%CI [0.90;0.95], p<0.001). ER and PR IHC % have significant, independent and similar impact on PFS achieved under 1st line by Pal + AI. The 14.1 months absolute mPFS obtained among pts with ER IHC <50% suggests that CDK4/6i + AI remains a good treatment option in this patient population.

581 Background: To evaluate the influence of loco-regional radiotherapy and adjuvant chemotherapy on the outcome of breast cancer patients with axillary lymph node micrometastases (MMTS) or isolated tumor cells (ITC). Methods: Between 1995 and 2005, 10,296 breast cancer patients were treated in our institution, 177 of them for unilateral breast cancer with MMTS (147) or ITC (30) by breast-conserving surgery or total mastectomy. The impact of chemotherapy and irradiation on overall survival (OS), disease-free survival (DFS) and metastases-free survival (MFS) were studied. Results: Median follow-up time was 77 months (mean 83.2 months), OS at 5 years 94.1 (89.2- 96.9), DFS 90.1 (84.4–93.9). No improvement in OS, DFS nor MFS were found in patients treated by supraclavicular irradiation (127/177), internal mammary lymph nodes (IMLN) irradiation (103/177) or axillary region irradiation (52/177). The OS, DFS and MFS were similar in patients with (93) or without (84) chemotherapy. Conclusions: Neither loco-regional radiotherapy nor adjuvant chemotherapy influenced the outcome of breast patients with MMTS or ITC. No significant financial relationships to disclose.

e11539 Background: The increased use of neoadjuvant chemotherapy (CT) in breast cancer (BC) management has raised new questions regarding the optimal locoregional treatment. The aim of this retrospective study was to compare the outcomes of BC patients (pts) with pathological N0 status (pN0) following primary CT and conservative surgery who received breast radiotherapy with or without lymph node irradiation. Methods: Between 1990 and 2004, 1054 patients received preoperative CT for locally advanced BC. Data from 248 pts (23.5%) with clinical N0 (164 pts) or N1-N2 (84 pts) lymph node status at diagnosis and pN0 status after primary CT were studied. Among them, 93 pts (37.5%) received breast irradiation alone and 155 pts (62.5%) underwent locoregional irradiation. Outcome was assessed in relation to lymph node recurrence, disease-free survival (DFS) and overall survival (OS). Results: Both groups were comparable in terms of baseline characteristics. With a median follow-up of 88 months, 3 pts experienced nodal recurrence in the breast irradiation alone group compared with 2 pts in the locoregional irradiation group (p>.05). Among the 164 N0 pN0 pts, the 5-year DFS and OS rates were respectively 84% and 89% vs 84% and 95%, according to whether they received (n=87) or not (n=77) lymph node irradiation(p>.05). Among the 84 N1-N2 pN0 pts, same outcome values did not show any significant difference according to group of treatment: 72% and 88% in 68 pts treated with locoregional irradiation vs 81% and 81% in 16 pts treated with breast irradiation alone (p>.05). Conclusions: Our results suggest that breast irradiation alone is not associated with a higher risk of regional recurrence in locally advanced BC pts with pN0 status after neoadjuvant chemotherapy. Whether this allows the omission of lymph node irradiation for such strategy should be addressed prospectively. No significant financial relationships to disclose.

Apparently localized breast cancer which has been treated with optimal locoregional therapy can recur months or years later, ultimately resulting in death. This is generally believed to be due to the development of occult micrometastases disseminated in the body and already present at the time of the initial surgery. Destruction of these micrometastases is the aim of adjuvant and neoadjuvant therapy. Adjuvant therapies have been widely used since the 1970s and, although the absolute survival benefit they confer is modest (10%), they have been credited, together with screening and improvement of loco-regional treatment, for the reduction in breast cancer mortality observed in recent decades.

The value of lymph node irradiation (LNI) for breast cancer (BC) patients with pathologic N0 status (pN0) after neoadjuvant chemotherapy (NAC) and breast-conservative surgery (BCS) is unknown. We compared the outcomes of pN0 patients following NAC and BCS who received breast radiotherapy (BRT) with or without LNI. Among 1,054 BC patients treated with NAC between 1990 and 2004, 248 patients (23.5%) had pN0 status after NAC and BCS. We limited our study to the patients who were treated with BCS as all patients who were selected for postmastectomy irradiation had LNI. Demographic data, tumor characteristics, and treatments were prospectively recorded. Outcome was assessed in relation to locoregional recurrence-free survival (LRR-FS), disease-free survival (DFS), and overall survival (OS). Among 248 patients (T1–T2: 193 patients, T3: 41 patients, T4: 14 patients, cN0: 164 patients, cN1–N2: 84 patients), 158 (63.7%) received BRT and LNI and 90 (36.3%) received BRT alone. Younger age (p = 0.005), N1–N2 clinical lymph node status at diagnosis (p = 0.0001) and internal or central localizations (p < 0.00001) were associated with LNI. With a median follow-up of 88 months (15–218), 2 patients experienced nodal recurrence in the BRT and LNI group compared with 3 patients in the BRT group. The 5-year LRR-FS rates were 89.4% in the BRT and LNI group compared with 86.2% in the BRT group (p > 0.5). Among 164 cN0 pN0 patients, the 5-year DFS and OS rates were 83% and 89.3% vs. 85% and 94.5%, respectively, according to whether they received LNI (n = 89) or not (n = 75; p > 0.05). Among 84 cN1–N2 pN0 patients, the 5-year DFS and OS rates were 72% and 87.9% vs. 79.4% and 80%, respectively, according to whether they received LNI (n = 69) or not(n = 15; p > 0.05). In a multivariate analysis, absence of pathologic complete response of the tumor (hazard ratio [HR] = 3.05; 95% CI, 1.17–7.99; p = 0.023) and N1–N2 clinical status at diagnosis (HR, 2.24; 95% CI, 1.15–4.36; p = 0.017) were associated with worse survival. Omission of LNI had no effect on either DFS (HR, 1.18; 95% CI, 0.64–2.15) or OS (HR, 1.19; 95% CI, 0.48–2.94). Our results suggest that BRT alone is not associated with a higher risk of LRR or death in BC patients with pN0 status after NAC. Whether this allows the omission of LNI for such strategy should be addressed prospectively.

La tomothérapie hélicoïdale est un équipement de radiothérapie innovant qui permet de faire uneimagerie en coupe et une irradiation conformationnelle avec modulation d'intensité (RCMI) avec le même accélérateur situé dans un anneau. Les premières évaluations nationales ont été réalisées dans le cadre d'un appel à projet de l'INCa sur les techniques innovantes en radiothérapie et confirment la faisabilité des traitements. Les principales applications cliniques découlent des caractéristiques dosimétriques obtenues en RCMI avec cet équipement, avec la possibilité de délivrer une irradiation homogène dans des volumes grands et complexes et d'éviter les organes à risque de contiguïté. L'imagerie embarquée en coupe permet de vérifier le positionnement et de réduire les marges autour des volumes cibles. Les premières évaluations dosimétriques comparatives sont discutées.Helical tomotherapy is an innovative device combining with the same linac on board-imaging and IMRT facilities. The first national French evaluations, supported by National Institut of Cancer (INCa) are presented. Dosimetric characteristics as quality of homogeneity, cut-off outside target volumes allow IMRT treatments for large andcomplex volumes and a good organ at risk sparing. First comparative dosimetric studies are discussed.

After a request for proposal initiated by National Institute against cancer (INCa) in 2005, three French centers in France started tomotherapy in the first semester of 2007. A national policy of evaluation was performed to study the feasibility of this innovative technique and to compare the interest of helicoidal tomotherapy with other modalities of conformal therapy. Common protocols have been designed to facilitate this evaluation. Description of dose, IMRT levels and constraints are achieved according to each selected indication as: sarcoma, head and neck tumors, lung cancer, mesothelioma, bone metastases, anal carcinoma and craniospinal irradiation. (C) 2007 Elsevier Masson SAS. Tous droits reserves.

Dans le cadre de l'appel à projets soutenu par l'INCa (Institut national du cancer), l'évaluation nationale de la tomothérapie hélicoïdale comprend les études de faisabilité et les comparaisons dosimétriques pour les indications suivantes: sarcomes des tissus mous des membres et des parois, axiales et rétropéritonéales, tumeurs crâniennes et cérébrales à l'exception des gliomes, tumeurs de prostate de gravité moyenne, tumeurs de la sphère ORL et du massif facial justifiant une conservation salivaire, tumeurs du sein de volume complexe, carcinome bronchique non à petites cellules et mésothéliome en situation postopératoire, métastases osseuses, irradiation craniospinale et tumeur du canal anal. Pour chacune des indications sélectionnées, des protocoles communs ont été mis en place afin de faciliter une étude intercentre. Les objectifs, effectifs, critères d'indication, doses et contraintes de dose retenus sont décrits.

L'halitose, ou mauvaise haleine, est très fréquente chez l'adulte, mais sa fréquence reste mal évaluée chez l'enfant. Elle correspond en majeure partie à l'émission de composés sulfurés volatils nauséabond, dont l'hydrogène sulfuré et le méthyl mercaptan. Ses causes sont multiples, principalement stomatologiques et otorhino-laryngologiques (ORL) chez l'enfant. Un interrogatoire et un examen clinique soigneux sont nécessaires, éventuellement avec l'aide de juges d'odeurs. Les examens paracliniques disponibles sont actuellement peu nombreux, mais susceptibles d'être développés dans l'avenir. Le traitement est d'abord étiologique, mais il passe également par une hygiène rigoureuse de la sphère buccale, afin d'en éliminer les bactéries généatrices d'odeurs.

Dans l’approche therapeutique conservatrice du cancer du sein, un des buts de la radiotherapie est celui d’obtenir une dose homogene dans la totalite de la glandemammaire (et dans les aires ganglionnaires, lorsque cela est indique), en evitant les surdosages qui pourraient engendrer des reactions aigues ou tardives, et les sous-dosages qui pourraient etre a l’origine des recidives. Les organes a risque, dont la protection est necessaire, sont les poumons et le cœur (particulierement pour l’irradiation du sein gauche). Les techniques visant a reduire les toxicites cardiaques de la radiotherapie, sont d’autant plus recommandees lorsque d’autres traitements cardiotoxiques lui sont associes (anthracyclines et / ou trastuzumab).

Tumors of salivary glands arise mainly from the parotid gland. Magnetic Resonance Imaging (MRI) is mandatory not only to localize precisely the tumor within the gland but also to differentiate between benign and malignant neoplasms, in competition with cytology in fine-needle aspiration biopsy. Tumors without risk of transformation, such as adenolymphoma, are not systematically operated on. Indications of roentgenotherapy and irradiation volumes depend on histologic type, localisation and size of the tumor.

Les tumeurs des glandes salivaires sont dominées en fréquence par les tumeurs parotidiennes. L'IRM est au premier plan de la stratégie diagnostique et permet une approche histopathologique de nature aussi fiable que la cytoponction dans un grand nombre de cas. Les lésions sans potentiel malin comme l'adénolymphome ou les kystes ne sont plus systématiquement opérées. Les indications de la radiothérapie et les volumes d'irradiation sont déterminés en fonction du type histologique, de la localisation et de la taille de la tumeur.