Abstract P4-10-16: Neoadjuvant chemotherapy infusion in the arm ipsilateral to breast cancer increases the risk of lymphedema

Background: Neoadjuvant chemotherapy (NAC) has been administered to clinically axillary positive breast cancer (BC) patients. Current guidelines still recommend axillary lymphadenectomy (AL) in patients with persistent positive axillary lymph node disease. We aimed to evaluate the association of NAC and/or adjuvant chemotherapy (CT) infusion in the ipsilateral upper limb (IA) with AL and the occurrence of lymphedema (LE) secondary to BC treatment. Methods: A prospective cohort study of 683 women subjected to AL and treated with NAC and/or adjuvant CT for BC. The patients were evaluated before treatment, immediate and every 6 months after surgery. Cumulative incidence and population attributable risks of LE were calculated. Results: 8-year cumulative incidence of LE was 33.1%. NAC and CT infusion and infusion of >2 cycles into the IA respectively increased by 1.68, 1.67 and 1.78 times the risk of LE respectively (all P<0.01). LE could be avoided in 9.4% of cases if the CT infusion had not been administered in the IA. Conclusions: 33.1% of women developed LE. The risk of LE was increased among women who received CT in the IA. Avoidance of NAC or adjuvant CT in the IA could prevent 9% of the LE cases observed in this population.

Citation Format: Bergmann A, Bello MA, Thuker LC, Andrade MF, Bevilacqua JI. Neoadjuvant chemotherapy infusion in the arm ipsilateral to breast cancer increases the risk of lymphedema [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr P4-10-16.

Impact of HER2 Status on Risk of Sentinel Node Metastasis: An Independently Validated Multivariable Model

Purpose The presence of axillary lymph node metastases is dictated by tumor biology and is a strong prognostic indicator in breast cancer. We have previously published a user-friendly nomogram that provides a risk estimate for sentinel lymph node (SLN) metastasis in women with breast cancer (Bevilacqua et al. 2007, J Clin Oncol 25: 3670). At that time, HER2 testing was not uniformly performed, but is now standard of care. The purpose of this study was to determine if the addition of HER2 status or grouping of patients by molecular subtype improves the prediction of SLN metastasis.Patients and Methods: The ability of clinical and pathologic features to predict the presence of SLN metastasis in patients presenting with clinically node negative invasive breast cancer, was assessed with multivariable logistic regression (MVA) for 4723 sequential SLN biopsy procedures with known ER, PR, and HER2 from 1996 to 2004. HER2 status was defined as positive if IHC=3+ and/or FISH≥2. The modeling (n=3297) and validation (n=1426) groups were identified by simple random sampling. Two models were created using the modeling population: one included ER, PR, and HER2 as separate variables and one combined these markers into 4 subtypes defined as: Luminal A-like=ER or PR +, HER2 −; Luminal B-like=ER or PR +, HER2 +; HER2-like=ER and PR −, HER2 +; Basal-like=ER and PR −, HER2 −. The validation group was used to assess the calibration (intercept, slope, Emax, Eavg) and discrimination (AUC, area under the receiver operating curve) of the models.Results: In addition to age, tumor size, tumor type, lymphovascular invasion, tumor location, and multifocality, subtype was found to be an independent predictor of SLN metastasis on MVA (p=0.003). The Basal-like subtype was associated with a significantly lower risk of SLN metastasis (compared with referent Luminal A-like subtype, OR=0.58). HER2 alone was not found to be an independent predictor of SLN metastasis (p=0.56), while ER and PR remained significant (p=.05, p=.02). Compared to our previous model without HER2, the AUC was slightly decreased by the addition of either HER2 or subtype into the model, but the calibration was slightly improved (Table 1). DiscriminationCalibrationModelAUCInterceptSlopeEmaxEavgPrevious Model0.735- 0.0440.8690.0390.020Mew model with HER20.733- 0.0030.8890.0270.019New model with subtype0.731- 0.0010.8870.0270.020Table 1: Discrimination and calibration measures comparing the new model (with HER2 alone or subtype) with the previously published model (without HER2 or subtype).Conclusion: The addition of subtype, defined by combining HER2 status with ER and PR, slightly increases the calibration of the new model but does not increase its discrimination compared to the previous model. Breast tumor subtype is a significant independent predictor of risk of SLN metastasis, with basal-like subtype having a lower risk of SLN metastasis.

Citation Information: Cancer Res 2009;69(24 Suppl):Abstract nr 1004.

A prospective validated model for predicting axillary node metastases based on 2,000 sentinel node procedures: the role of tumour location [corrected]

AIMS

The purpose was to identify the independent predictive factors of axillary lymph-node metastases (ALNM) in infiltrating ductal carcinoma (IFDC) and to create a prospective, validated statistical model to predict the likelihood of ALNM in patients in the present era of sentinel lymph-node (SLN) biopsy and enhanced histopathology.

METHODS

Univariate and multivariate analyses of 13 clinicopathological variables (including tumour location) were performed to determine predictors of ALNM in 1659 eligible SLN biopsy procedures. A logistic regression model was developed and then prospectively validated on a second population of 187 subsequent consecutive procedures.

RESULTS

Age, pathological tumour size, palpability, lymphovascular invasion (LVI), histological grade, nuclear grade, ductal histological subtype, tumour location (quadrant) and multifocality were associated with ALNM in univariate analyses (P < 0.001). Of these, only palpability and histological grade were not statistically associated with ALNM in the multivariate analysis (P> 0.05). The frequency of ALNM in upper-inner-quadrant (UIQ) tumours was 20.6%, compared with 33.2% for all other quadrants (P<0.0005). There was no statistical difference between UIQ and other-quadrant tumours in any clinicopathological variables analysed. The logistic regression model, developed based on the population of 1659, had the same accuracy, sensitivity, specificity, positive predictive value and negative predictive value when applied prospectively to the second population.

CONCLUSION

Tumour size, LVI, age, nuclear grade, histological subtype, multifocality and location in the breast were independent predictive factors for ALNM in IFDC. ALNM is less frequent in UIQ tumours than in other-quadrant tumours. Our prospectively validated predictive model could be valuable in pre-operative patient discussions, although staging of the axilla in the individual patient remains necessary.

Diphtheria and tetanus immunity among blood donors in Toronto

OBJECTIVE

To determine the diphtheria and tetanus antitoxin levels among blood donors in Toronto.

DESIGN

Cross-sectional seroprevalence study.

SETTING

Two fixed-site blood-donation clinics in Toronto from September to November 1994.

PARTICIPANTS

Blood donors 20 years of age or older were eligible to participate; of the 781 eligible donors, 710 (90.9%) participated in the study.

MAIN OUTCOME MEASURES

Diphtheria and tetanus antitoxin levels and factors associated with disease susceptibility, such as vaccination history, country of birth, age and sex. A diphtheria antitoxin level lower than 0.01 lU/mL and a tetanus antitoxin level lower than 0.15 lU/mL were considered nonprotective.

RESULTS

Among the participants, 147 (20.7%) had a diphtheria antitoxin level in the nonprotective range, and 124 (17.5%) had a tetanus antitoxin level that was nonprotective. Increasing age and lack of written vaccination records were associated with susceptibility to the 2 diseases. Birth outside Canada was significantly related to tetanus susceptibility.

CONCLUSION

Adults over 50 years of age who did not know their vaccination history were the least likely to be protected against diphtheria and tetanus. The greatest benefit of any immunization strategy would be gained by targeting this group.

Central sleep apnea in hypothyroidism

This is a report of a 45-yr-old male patient who developed central sleep apnea syndrome because of hypothyroidism. In response to L-thyroxine therapy, the patient became euthyroid, and the apneic phenomenon disappeared. Previous reports have suggested that hypothyroidism can produce obstructive sleep apnea from either narrowing of the upper airway secondary to deposition of mucopolysaccharides and protein extravasation into the tissues or from abnormalities in ventilatory control. The present patient did demonstrate evidence of profound dysfunction of his respiratory control center: before therapy, the patient manifested blunted ventilatory and occlusion pressure responses to hypoxia and normal responsiveness to hypercapnia; after therapy, hypoxic responsiveness was restored and the ventilatory response to hypercapnia doubled. Hypothyroidism should be included in the differential diagnosis of central sleep apnea.