Non sentinel node involvement prediction for sentinel node micrometastases in breast cancer: nomogram validation and comparison with other models.

PURPOSE: The risk of non sentinel node (NSN) involvement varies in function of the characteristics of sentinel nodes (SN) and primary tumor. Our aim was to determine and validate a statistical tool (a nomogram) able to predict the risk of NSN involvement in case of SN micro or sub-micrometastasis of breast cancer. We have compared this monogram with other models described in the literature. METHODS: We have collected data on 905 patients, then 484 other patients, to build and validate the nomogram and compare it with other published scores and nomograms. RESULTS: Multivariate analysis conducted on the data of the first cohort allowed us to define a nomogram based on 5 criteria: the method of SN detection (immunohistochemistry or by standard coloration with HES); the ratio of positive SN out of total removed SN; the pathologic size of the tumor; the histological type; and the presence (or not) of lympho-vascular invasion. The nomogram developed here is the only one dedicated to micrometastasis and developed on the basis of two large cohorts. The results of this statistical tool in the calculation of the risk of NSN involvement is similar to those of the MSKCC (the similarly more effective nomogram according to the literature), with a lower rate of false negatives. CONCLUSION: this nomogram is dedicated specifically to cases of SN involvement by metastasis lower or equal to 2 mm. It could be used in clinical practice in the way to omit ALND when the risk of NSN involvement is low.

Kinetics of HER2/neu ECD in 45 patients treated with trastuzumab (Herceptin) between January 2001 and June 2005 at the Grenoble University Hospital.

UNLABELLED: The aim of this study was to evaluate the utility of HER2/neu ECD concentration as a marker of the efficacity of clinical response to Herceptin. PATIENTS AND METHODS: Iterative measurements of HER2/neu ECD (ELISA c-erbB2/c-neu Rapid Format Elisa kit QIA10 Calbiochem) concentrations in 45 patients treated with Herceptin between January 2001 and June 2005 at the Grenoble University Hospital. RESULTS: Changes in HER2/neu ECD concentrations were observed in 21 patients (47%). The baseline concentration was the concentration of circulating HER2/neu ECD before treatment with Herceptin. In 15 patients, the mean baseline concentration was 52 ng mL(-1) (extreme values 13-170), which normalized no later than at the time of the 3rd administration of Herceptin. Nine patients (60%) were still alive 5 years later (p<0.05). For 6 patients, the mean baseline concentration was 800 ng mL(-1) (extreme values 140-2000) which persisted and even increased during Herceptin therapy; fewer than 25% were alive 30 months later (p<0.05). In the case of the 24 patients whose HER2/neu ECD concentration remained <5 ng mL(-1), survival time was intermediate. CONCLUSION: The study confirmed the utility of HER2/neu ECD in predicting therapeutic response. However, as in the case of other circulating tumor markers, it is only useful when there is a variation in concentration. This marker should now be evaluated in multi-center studies covering a large number of homogeneous subjects.

Can the sentinel lymph node technique affect decisions to offer internal mammary chain irradiation?

PURPOSE: Identification of the sentinel lymph node (SLN) for small mammary tumours (cT1N0) sometimes leads to detection of internal mammary chain (IMC) drainage. This information is often ignored by physicians. The present study sought to determine the frequency with which an internal mammary SLN was identified by peritumoral injection of radioactive tracer, and then to determine the patients in whom identification of an internal mammary SLN could have an impact on the radiation treatment plan. MATERIALS: Between March 2002 and March 2008, 622 SLN biopsies performed in a cohort of 608 patients were analysed. Technetium-labelled nanocolloids were administered via three peritumoral injections, completed by a deep prepectoral injection, with the entire procedure performed under echographic guidance. RESULTS: The SLN was identified in 607 of the 622 patients, including 174 (28.7%) in the IMC. A total of 161 successful internal mammary biopsies were performed. Of the 622 patients, 18 showed SLN involvement in the IMC. In 7 of these patients, only the internal mammary SLN was affected. Prophylactic irradiation of the IMC was indicated in 376 patients, but only in 18 (4.8%) of these patients was there effectively IMC involvement; internal mammary SLN biopsy failed in 7 patients (1.9%). CONCLUSION: SLN detection by peritumoral injection, combined with the systematic removal of the internal mammary SLN, enabled the involvement of this region to be found in a nonnegligible number of patients. Such information should make it possible to personalize treatment for patients with stage cT1 mammary cancer and thereby avoid needless internal mammary radiation therapy in a large number of patients (93.4% in our study).

Evaluation of a manual ELISA kit for determination of HER2/neu in serum of breast cancer patients.

BACKGROUND: Our aim was to conduct an analytical validation in a routine laboratory setting of the cerb-B2/c-neu ELISA assay kit from Calbiochem used to measure the extracellular domain (ECD) of HER2/neu in the serum of breast cancer patients. MATERIALS AND METHODS: The evaluation was based on three different production lots used in a routine laboratory setting. The reference value was based on a population of 217 patients with breast cancer not overexpressing HER2. RESULTS: The detection limit, below that given by the manufacturer, was 0.34 ng ml(-1) and the quantification limit was 0.90 ng ml(-1). Reproducibility and repeatability were at least 95%, precision coefficients of variation varied between 6 and 8.5% and trueness measured by dilution tests and the standard additions method varied between 97 and 107%. The threshold was estimated at 5 ng ml(-1). CONCLUSION: This technique presents satisfactory levels of accuracy for routine laboratory use.

Prospect for anti-HER2 receptor therapy in breast cancer.

The carcinogenesis process is characterized, in part, by the dysfunction of cellular communication pathways, such as the one involving HER2. HER2 is a member of the EGF receptor family, which participates in cell growth and proliferation. HER2 may be overexpressed in 15 to 30% of breast cancer cases and is associated with poor prognosis, shortened overall survival and shorter time to disease progression. Furthermore, an increasing number of studies have demonstrated the relevance of HER2 serum concentrations (sHER2, extracellular domain released into blood by proteolysis) as a predictive marker of resistance to chemotherapy in HER2-overexpressing metastatic breast cancer. The determination of HER2 overexpression/ amplification in the diagnosis of relapse of breast cancer is currently a routine procedure. Immunohistochemistry (IHC) and fluorescent in situ hybridization (FISH) techniques, which are used to detect HER2 expression in the tumor, are improving constantly, and other parallel techniques such as chromogenic in situ hybridization (CISH) are starting to emerge. sHER2 concentrations can be measured using ELISA techniques, which can be automated. All of these procedures still need to be standardized. The discovery of a monoclonal antibody (4D5) that can inhibit the growth and proliferation of cells overexpressing HER2 led to the development of trastuzumab. Like 4D5, trastuzumab recognizes an epitope on the extracellular domain of HER2. Moreover, trastuzumab is also able to stimulate antibody-dependent cellular toxicity (ADCC). It is administered alone or in combination (with navelbine, taxol, carboplatin...) in patients with metastatic breast cancer overexpressing HER2. Other active antibodies have since been discovered, as well as other specific molecules, such as tyrosine kinase inhibitors which will undoubtedly find a place in the therapeutic arsenal used in breast cancer, especially to avoid the emergence of resistance to treatment.

Prospect for anti-her2 receptor therapy in breast cancer.

The carcinogenic process is characterized, in part, by the dysfunction of cellular communication pathways, such as the one involving HER2. HER2 is a member of the EGF receptor family, which participates in cell growth and proliferation. HER2 may be overexpressed in 15 to 30% of breast cancer cases and is associated with poor prognosis, shortened overall survival and shorter time to disease progression. Furthermore, an increasing number of studies have demonstrated the relevance of HER2 serum concentrations (sHER2, extracellular domain released into the blood by proteolysis) as a predictive marker of resistance to chemotherapy in HER2-overexpressing metastatic breast cancer. The determination of HER2 overexpression/ amplification in the diagnosis of relapse of breast cancer is currently a routine procedure. Immunohistochemistry (IHC) and fluorescent in situ hybridization (FISH) techniques, used to detect HER2 expression in the tumor, are improving constantly and other parallel techniques such as chromogenic in situ hybridization (CISH) are emerging. sHER2 concentrations can be measured using ELISA techniques, which can be automated. All of these procedures still need to be standardized. The discovery of a monoclonal antibody (4D5) that can inhibit the growth and proliferation of cells overexpressing HER2 led to the development of trastuzumab. Like 4D5, trastuzumab recognizes an epitope on the extracellular domain of HER2. Moreover, trastuzumab is also able to stimulate antibody-dependent cellular toxicity (ADCC). It is administered alone or in combination (with navelbine, taxol, carboplatin, etc.) in patients with metastatic breast cancer overexpressing HER2. Other active antibodies have since been discovered, as well as other specific molecules, such as tyrosine kinase inhibitors which will undoubtedly find a place in the therapeutic arsenal used in breast cancer, especially to avoid resistance to treatment.