Impact of overweight, obesity, and post-treatment weight changes on occupational reintegration of breast cancer (BC) survivors

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Background: Overweight and obesity are strongly linked to poorer BC-specific outcomes, quality of life and financial burden in cancer care. Weight loss interventions have the potential to improve such outcomes. Fewer data exist on whether excess weight and post-diagnosis weight changes impact the ability of BC survivors to return to work (RTW). Methods: CANTO (NCT01993498) is a multicenter prospective longitudinal study of 12000 patients (pts) with stage I-III BC that characterizes long-term toxicities of BC treatment. Of 5801 pts enrolled from 2012-2014 (last data lock), we identified 1874 pts who were professionally active at BC diagnosis, ≥5 years (yrs) younger than minimum legal retirement age (62 yrs) and with updated work status 2 yrs after diagnosis. Logistic regression models evaluated the impact of body mass index (BMI) at diagnosis and of weight changes over 2 yrs after diagnosis on odds of non-RTW, adjusting for age, education, income, BC treatment and recreational physical activity (PA). Results: 37% pts were overweight or obese at diagnosis (BMI ≥25 kg/m2): 34% of them gained ≥5% and 16% lost ≥5% weight after diagnosis. Rates of non-RTW at 2 yrs were significantly higher in overweight or obese vs under or normal weight pts (27% vs 18%, p≤.001; adjusted odds ratio 1.37, 95% Confidence Interval [CI] 1.04-1.80, p = .017). Overweight and obese pts who did not RTW experienced higher increments in weight (mean [95% CI]: +3.6% [+2.3, +4.9] vs +1.5% [+0.8, +2.2]) and reported more modest changes in PA (mean [95% CI]: +1.0 [-1.4, +3.5] vs +2.1 [+0.8, +3.3] MET-h/week) vs those who did RTW. Weight changes independently impacted odds of non-RTW in overweight and obese pts (p for interaction weight change*BMI ≤.001): a 5% weight gain was associated with 17% increase in adjusted odds of non-RTW (95% CI 2-35%, p = .024), whereas a loss ≥5% with 60% reduced odds of non-RTW vs weight gain (95% CI 18-82%, p = .013). Conclusions: Excess weight and weight changes are significantly associated with occupational reintegration after BC in overweight and obese pts. Randomized studies testing dedicated weight control interventions should also measure outcomes of social rehabilitation in this large subset of survivors. Clinical trial information: NCT01993498.

Effect of Buparlisib, a Pan-Class I PI3K Inhibitor, in Refractory Follicular and Poorly Differentiated Thyroid Cancer

BACKGROUND

Dysregulation of the phosphatidylinositol 3-kinase (PI3K) pathway is frequent in advanced follicular (FTC) and poorly differentiated thyroid (PDTC) carcinomas and has been implicated in oncogenesis and tumor progression. This study investigated the efficacy and safety of buparlisib, a pan-PI3K inhibitor in radioiodine refractory FTC and PDTC.

METHODS

The primary endpoint of this open-label, multicenter, phase 2 pilot study was progression-free survival (PFS) at 6 months. The sample size was determined considering that a PFS ≤50% at 6 months would denote an absence of benefits (null hypothesis). Secondary endpoints were objective response rate, PFS at 12 months, overall survival at 6 and 12 months, and safety based on the frequency and severity of adverse events (AEs).

RESULTS

Forty-three patients (19M/24 F; median age: 67 years) with metastatic, radioiodine refractory, progressive disease received buparlisib, 100 mg, daily. Histology was PDTC in 25 (58%), FTC in 17 (40%), and Hürthle cell carcinoma in 1 (2%). RAS mutation was found in 44% (12/27) and activation of the PI3K pathway in 35% (8/23) of tested tumors. The probability of PFS was 41.7% [95% confidence interval (CI) 7.7-55.5] at 6 months and 20.9% [CI 0-35.7] at 12 months, lower than the 50% expected PFS. At 6 months, 25.6% patients had stable disease, 48.8% were progressive and 25.6% had stopped treatment due to AE. The response to therapy was not influenced by age, sex, histology, or genetic alterations. The overall survivals at 6 and 12 months were 85.9% [CI 76-97] and 78.7 % [CI 67-92], respectively. The mean tumor growth rate decreased from 3.78 mm/month [CI 2.61-4.95] before treatment to 0.8 mm/month [CI -0.2-1.88] during treatment (p < 0.02). Severe grade 3-4 AEs occurred in 27 patients (63%), including hepatitis (25%), hyperglycemia (21%), mood disorders (12%), and skin toxicity (12%), with favorable outcome after temporary or permanent treatment discontinuation or dose reduction.

CONCLUSIONS

Buparlisib did not result in significant efficacy in advanced FTC and PDTC. However, the decrease in tumor growth rate may suggest incomplete inhibition of oncogenic pathways and/or escape mechanisms. This should lead to evaluate combined therapy associating inhibitors of both the PI3K and mitogen-activated protein kinase pathways.

Non-adherence behaviors among young women on adjuvant endocrine therapy for breast cancer

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Background: Young age at diagnosis (dx) is a predictor of worse prognosis in patients (pts) with luminal breast cancer (BC). Poorer adherence to endocrine therapy (ET) among younger women may contribute to this disparity. Aim: To assess non-adherent behaviors and associated factors among young women with stage 1-3 hormone receptor (HR)+ BC taking ET. Methods: This study is a part of a multi-center, prospective cohort of pts with dx of BC at or under age 40. On a survey 30 months after dx, among pts reporting taking ET, adherence was measured using a 3-item Likert-type scale (Do you ever forget to take your ET? If you feel worse when you take your ET, do you stop taking it? Did you take your ET exactly as directed by your doctor?). Pts reporting any non-adherent behavior during the last 3 months were classified as non-adherers. Variables with a p-value <0.20 were included in a multivariate logistic model. Results: Among361 pts eligible for this analysis, 174 (48%) reported some non-adherent behaviors in the last 3 months; 56 (16%) moderate or greater non-adherent behaviors. None of the studied variables was associated with non-adherent behaviors (table). Conclusions: Non-adherent behaviors to ET are present in almost half of the young women with HR+ BC. Further analyses of explanatory factors and impact of non-adherence are required to understand and potentially improve this problem. [Table: see text]

Outcomes and Prognostic Factors in Radioiodine Refractory Differentiated Thyroid Carcinomas

BACKGROUND

Outcomes vary among patients with radioiodine refractory (RR) differentiated thyroid cancer (DTC). The prognostic factors for survival are not well-known, resulting in difficulty in selecting patients for new targeted therapies. We assessed overall survival (OS) and cancer-specific survival (CSS) from RR-DTC to identify prognostic factors associated with survival.

PATIENTS AND METHODS

The data on all cases of metastatic RR-DTC treated in our center from 1990 to 2011 were retrospectively reviewed. Survival was estimated using the Kaplan-Meier method; associated prognostic factors were assessed using Cox's model.

RESULTS

Of 153 cases of metastatic DTC, 59% (n = 91) met a criterion for RR: that is, 60% (n = 55) had at least 1 metastasis without (131)I uptake; 21% (n = 19) had progressive disease (PD) despite (131)I; 19% (n = 17) had persistent disease despite a cumulative activity of (131)I of ≥600 mCi. After the diagnosis of RR, median OS was 8.9 years (95% confidence interval [CI]: 5.4-NR); median CSS was 9.6 years (95% CI: 6.01-NR). In multivariate analyses, PD despite (131)I as a criterion for RR disease and the time from initial diagnosis of DTC to diagnosis of RR <3 years were the only independent prognostic factors for poor OS and CSS. Thyroglobulin doubling time (Tg-DT) was assessed in 31 of 91 cases. Among the 11 patients with Tg-DT for <1 year or undetectable Tg, 6 deaths occurred, whereas only 3 died of 20 patients with Tg-DT >1 year or negative Tg-DT.

CONCLUSION

The identification of prognostic factors for decreased survival in RR-DTC may improve the selection of patients for targeted agents.

IMPLICATIONS FOR PRACTICE

This study shows a great heterogeneity in terms of prognosis in radioiodine refractory differentiated thyroid carcinoma. Poorer prognosis is observed in patients with tumor progression or with a diagnosis of radioiodine resistance within 3 years after the initial diagnosis of thyroid cancer. Those findings could lead to improvements in the selection of patients for targeted therapies.

Evaluation of antiangiogenic efficacy in advanced hepatocellular carcinoma: Biomarkers and functional imaging

Many years after therapeutic wilderness, sorafenib finally showed a clinical benefit in patients with advanced hepatocellular carcinoma. After the primary general enthusiasm worldwide, some disappointments emerged particularly since no new treatment could exceed or at least match sorafenib in this setting. Without these new drugs, research focused on optimizing care of patients treated with sorafenib. One challenging research approach deals with identifying prognostic and predictive biomarkers of sorafenib in this population. The task still seems difficult; however appropriate investigations could resolve this dilemma, as observed for some malignancies where other drugs were used.

Alternative Response Criteria (Choi, European association for the study of the liver, and modified Response Evaluation Criteria in Solid Tumors [RECIST]) Versus RECIST 1.1 in patients with advanced hepatocellular carcinoma treated with sorafenib

INTRODUCTION

Response Evaluation Criteria in Solid Tumors, version 1.1 (RECIST 1.1), may underestimate activity and does not predict survival in patients with hepatocellular carcinoma (HCC) treated with sorafenib. This study assessed the value of alternative radiological criteria to evaluate response in HCC patients treated with sorafenib.

PATIENTS AND METHODS

A retrospective blinded central analysis was performed of computed tomography (CT) scans from baseline and the first tumor evaluation in consecutive patients treated with sorafenib over a 2-year period in a single institution. Four different evaluation criteria were used: Choi, European Association for the Study of the Liver (EASL), modified RECIST (mRECIST), and RECIST 1.1.

RESULTS

Among 82 HCC patients, 64 with Barcelona Clinic Liver Cancer stage B-C were evaluable with a median follow-up of 22 months. Median duration of sorafenib treatment was 5.7 months, and median overall survival was 12.8 months. At the time of the first CT scan, performed after a median of 2.1 months, Choi, EASL, mRECIST, and RECIST 1.1 identified 51%, 28%, 28%, and 3% objective responses, respectively. Responders by all criteria showed consistent overall survival >20 months. Among patients with stable disease according to RECIST 1.1, those identified as responders by Choi had significantly better overall survival than Choi nonresponders (22.4 vs. 10.6 months; hazard ratio: 0.43, 95% confidence interval: 0.15-0.86, p = .0097).

CONCLUSION

Choi, EASL, and mRECIST criteria appear more appropriate than RECIST 1.1 to identify responders with long survival among advanced HCC patients benefiting from sorafenib.

Abstract P6-12-13: Synchronous metastases are highly prevalent in HER2 positive inflammatory breast carcinomas evaluated by 18F-FDG PET/CT

Background: Inflammatory breast carcinomas have poor prognosis even in the absence of evident synchronous metastases. 18F-FDG PET/CT is not recommended in initial staging but could improve the sensibility of synchronous metastases detection and the management of the patients.

Objective: To assess factors associated with synchronous metastases in inflammatory breast carcinomas when evaluated by 18F-FDG PET/CT.

Methods: Since 2006, initial staging of locally advanced breast carcinomas in our center consisted of 18F-FDG PET/CT in addition to standard laboratory and radiological tests. We reviewed data of patients with inflammatory breast carcinomas treated from 2006 to 2013 who had an initial evaluable18F-FDG PET/CT. Fisher's exact test and logistic model were used to assess factors associated with synchronous metastases. Overall survival was estimated with the method of Kaplan-Meier.

Results: Among 353 locally advanced breast carcinomas seen at the breast disease unit, hospital Saint Louis from 04/2006 to 04/2013, we identified 40 inflammatory breast carcinomas. Initial 18F-FDG PET/CT was available for review in 32 inflammatory breast carcinomas. Median age was 57 years (range 38-78), 39% had pre-menopausal status (n = 12), clinical node involvement was found in 87.5% (n = 28). Histological features on biopsy were: ductal invasive carcinoma 91% (n = 29), SBR grade III 72% (n = 23), negative hormonal receptor 75% (n = 24), positive HER2 37.5% (n = 12), triple negative 44% (n = 14). Synchronous metastases were found in 41% of inflammatory breast carcinomas (n = 13), bone (n = 7), liver (n = 6) and mediastinum (n = 4). Synchronous metastases seemed more common in HER2 positive than in HER2 negative inflammatory breast carcinomas (58% vs 30%, p = 0.15). In multivariate analysis, no factor was associated with synchronous metastases. All patients with inflammatory breast carcinomas received neoadjuvant chemotherapy with sequential anthracycline and taxane (16 patients), dose-dense anthracycline and alkylating agent (8 patients), taxane with or without bevacizumab (7 patients) and anthracycline in 1 patient. Trastuzumab was given in all HER2 positive inflammatory breast carcinomas. Clinical response to neoadjuvant chemotherapy was complete in 16.5% (n = 5), partial in 67% (n = 20), stable or progressive in 16.5% (n = 5) and missing for 1 patient. One patient died before response assessment. Thirty patients (94%) underwent radical mastectomy with axillary node dissection. Pathologic complete response in breast and nodes was found in 27.5% (n = 8). Axillary node invasion was found in 45% (n = 13). All positive hormonal receptors patients received endocrine therapy after surgery. With a median follow-up of 33 months, 10 patients died. Median overall survival was 38.8 months (95%CI: 30.3-NA) with no difference between HER2 positive and HER2 negative patients.

Conclusion: Synchronous metastases are common in inflammatory breast carcinomas especially in case of HER2 positive tumors. Complete initial staging with 18F-FDG PET/CT could be useful to detect synchronous metastases mainly in bone and liver and thus allowed to adapt further treatment.

Citation Information: Cancer Res 2013;73(24 Suppl): Abstract nr P6-12-13.

Survival and prognostic factors of radioiodine refractory pulmonary metastatic differentiated thyroid carcinoma (DTC)

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Background: The challenging key point of management of radioiodine refractory DTC patients is to define those who could benefit from experimental drugs in clinical trials. Methods: We reviewed clinical and pathological data of patients with refractory pulmonary metastatic DTC treated in our center from 1990 to 2011. Survival was estimated with the method of Kaplan-Meier. Associated prognostic factors were studied in Cox model based analyses. Results: Among 167 pulmonary metastatic DTC, 46% (n=76) met a criterion of radioiodine refractory disease: at least one metastases without I131 uptake: 61% (n=46); progressive disease despite I131: 22% (n=17) and absence of complete response despite a cumulated dose >600mCi: 17% (n=13). There were 63% of female (n=48) and the median age was 64 years (range 18-87). The initial treatment was total thyroidectomy in 92% (n=70), lymph node dissection in 71%, (n=54) and radioiodine therapy in 100% of patients. Pathological features were papillary histology in 61% (n=46), follicular histology in 29% (n=22) and poor differentiated histology in 10% (n=8). pT stage was 1ab, 2, 3, and 4 in 11%, 13%, 63% and 13% respectively, pN stage after lymph node dissection was 0, 1a and 1b in 33%, 7% and 60% respectively. Metastasis were present at diagnosis in 45% (n=34) of cases. The refractory feature was established at the time of diagnosis and in the follow-up in 18% and 82% of cases respectively. When the disease was considered as refractory, the median overall survival was 5.5 years. The refractory feature at the initial diagnosis was the only independent prognostic factor correlated with poor survival (p<0.001). Conclusions: Patients who are considered as radioiodine refractory at the initial diagnosis of DTC have poor prognosis and should be considered for clinical trials in case of progression.

Impact of adjuvant trastuzumab-based chemotherapy in T1ab node-negative HER2 overexpressing breast carcinomas

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Background: HER2 overexpression has been recognized as a pejorative prognostic factor in node negative T1ab (T1abN0) breast tumors. Randomized clinical trials have shown benefit of adjuvant trastuzumab-based chemotherapy (ATBC) for node-positive and/or greater than 1 cm (T1c or more) HER2+ breast carcinomas. There are no prospective efficacy data of ATBC in T1abN0 HER2+ tumors. Methods: We retrospectively evaluated 276 cases of T1ab node-negative HER2+ breast tumors in 8 French Comprehensive Cancer Centers. We assessed clinical, therapeutic features and outcome. We estimated the probability of disease-free survival (DFS), analyzed associations of ATBC, patient and tumor characteristics with DFS and prognosis factors using the log-rank test, multivariate analysis with logistic regression and Cox’s proportional hazards model. Results: Out of the 276 T1abN0 cases, 129 (47%) received ATBC (ATBC+) and 123 (45%) were not treated by either trastuzumab or chemotherapy (ATBC-). Of these 252 ATBC+ or ATBC- patients, decision of ATBC was associated with date of diagnosis (before or after ASCO 2005 Annual Meeting when interim results from three trastuzumab adjuvant trials were reported) and with poor prognosis features: negative hormone receptors (HR-) status, Elston-Ellis high grade, tumor size > 5 mm and age. With a median follow-up of 44 months 16 recurrences were observed (13 in the ATBC- group, 2 in the ATBC+ and 1 with adjuvant chemotherapy alone). Nine recurrences were distant metastases. A survival benefit in ATBC+ was observed with a 99% 40-months DFS versus 93% for ATBC- (logrank p-test = 0.018). In an exploratory analysis, two factors were significantly associated with worst prognosis for ATBC- that were not observed for ATBC+ : HR- status (98% 40-months DFS for ATBC+ patients versus 84% for ATBC- patients; logrank p-test = 0.0003) and presence of lymphovascular invasion (100% 40-months DFS for ATBC+ versus 73% in ATBC- cases; logrank p-test = 0.003). Conclusions: In our seriesATBC is associated with a significant reduction of risk of recurrence of T1abN0 HER2+ tumors. A clear DFS benefit of ATBC was observed in HR- tumors and/or in presence of lymphovascular invasion.

Value of preoperative biopsy and radiological assessment for the diagnosis of mixed hepatocellular cholangiocarcinoma (HCC-CC)

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Background: Mixed tumors with hepatocellular and cholangiocarcinoma component (HCC-CC) are rare variants of primary liver tumors. In this study, we aimed to describe clinical, radiological and histopathological features of patients with resected HCC-CC.

Methods: From 2000 to 2010, patients (pts) with diagnosis of mixed HCC-CC based on surgical specimen were identified from our database. Demographic, clinical, radiological and pathological data were analyzed retrospectively, along with outcome after resection.

Results: Among 18 pts, 6 men (33%) and 12 women (67%) were identified. The median age was 64 years (range 38- 75). Nine pts (50%) had at least one risk factor for chronic liver disease including alcohol consumption (6), NASH (3) and HBV infection (2). Twelve (67%) and 6 pts (33%) underwent major and minor hepatic resections respectively. The positive predictive value of radiological and pathological diagnosis was reviewed. Imaging by CT scan and/or MRI suggested characteristics of HCC and CC in 5 and 6 pts respectively. In 3 pts imaging showed combined features of HCC and CC while it was atypical in 4 cases. Preoperative biopsy was performed in 10 pts and analyzed using only morphological features. Biopsy sample was non contributive in 2 cases and concluded to CC, HCC and mixed HCC-CC in 5, 2 and 1 cases respectively. This contrasted with examination of resection specimen showing evidence of HCC combined with CC phenotype. Immunostaining on resection specimens showed the presence of differentiation markers for both hepatocytes and biliairy cancer cells (CK7 +, CK19 +, anti-hepatocyte +, and glypican +). Non tumor liver analysis showed normal underlying liver, non extensive fibrosis ≤ F2, extensive fibrosis > F2 without cirrhosis and cirrhosis in 2, 3, 7 and 6 specimens respectively. With more than 6 months follow-up (range 6 -59 months) the recurrence rate was higher than 50%.

Conclusions: Mixed HCC-CC are not accurately identified by preoperative biopsy using only morphological features and CT scan/MRI assessment. Following resection, mixed HCC-CC behave more like CC than HCC.

Blinded independent central response assessment using RECIST, mRECIST, and CHOI criteria in patients treated with sorafenib for advanced hepatocellular carcinoma (HCC)

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Background: Despite survival benefit in patients with advanced HCC, sorafenib has been infrequently associated with changes in tumors dimensions, challenging standard RECIST criteria. Experts have suggested new response criteria based on changes in tumor vascularization and density (mRECIST and Choi). Aim is to evaluate response in patients treated with sorafenib using three different methods and their correlation with overall survival (OS)

Methods: Radiological evaluations were performed from consecutive patients treated with sorafenib from January 2007 to February 2009. Patients were considered evaluable if CT scans were performed within 6 weeks before sorafenib and in the three months following treatment initiation at the first evaluation. A radiologist blinded for clinical data performed tumor evaluations according to RECIST, mRECIST, and Choi criteria. Best response was correlated with OS

Results: Among 82 patients, 60 were evaluable (median age 63, male/female 52/8). The majority of patients were Child A (80%). Tumor staging showed BCLC stage B and C in 33% and 67%, respectively. The median duration of treatment with sorafenib was 6.6 months (range 1.2-16.5). Tumor evaluations by CT scan were performed in a median of 2.1 months (range 1.5-3.2). For the entire cohort, median OS was 9.9 months, and survival rates at 6, 12, and 24 months were 69%, 39% and 22%, respectively. The table summarizes the best responses measured using RECIST, mRECIST, and Choi criteria.

Conclusions: Better OS was observed in patients with complete/partial response than in patients with stable disease and progression, regardless the type of radiological criteria. However, mRECIST and Choi criteria identified more adequately than RECIST subgroups of patients with complete/partial response who also experienced longer survival

[Table: see text]

Rapamycin in patients with advanced hepatocellular carcinoma progressing on prior antiangiogenic therapy

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Background: PI3K/Akt/mTOR is a critical survival pathway in hepatocellular carcinoma (HCC) often correlated with poor prognosis. Rapamycin (sirolimus) and its analogue everolimus, are specific mTOR inhibitors that showed promising antitumor activity in preclinical models and clinical cases of HCC Aims: To evaluate the safety and efficacy of rapamycin in patients (pts) with advanced HCC after failure or intolerance to prior antiangiogenic therapy

Methods: In this retrospective cohort, we analyzed consecutive patients with progressive HCC after 1 to 3 lines of treatment including at least sorafenib. All pts received oral rapamycin at 20 to 30 mg once a week. Adverse events (AEs) were assessed using NCI-CTCAE v3.0, and tumor response was evaluated according to RECIST criteria.

Results: Nine patients (F/M: 1/8) with compensated liver cirrhosis (Child A, n = 6; Child B7, n = 2) or no cirrhosis (n=1) and histologically proven HCC were included in this study. Overall, therapy with rapamycin was well tolerated. Most common toxicities were asthenia (grade 1-2: 5 pts) anaemia (all grade: 5 pts; grade 3: 2 pts ) and thrombocytopenia (grade 1-2: 2 pts). Liver function deterioration was observed in 2 pts with advanced cirrhosis (Child B7). Radiological evaluation was available in 6 pts. No objective tumor response was observed however stable disease ≥ 3 months was observed in 4 cases. Moreover, 2 pts showed stable disease at 6 months. Prolonged stabilization under rapamycin was observed in pts who were previously controlled at least for 6 months with sorafenib. Rapamycin was discontinued due to disease progression in 7/8 pts, toxicity in 1/8 pts. One pt shows ongoing long-lasting disease stabilization (8 + months).

Conclusions: Rapamycin displayed an acceptable safety profile and may achieved disease stabilization in patients with heavily pretreated advanced HCC.

P2-18-03: Systemic Adjuvant Treatment of T1a and T1b N0M0 HER2+ Breast Carcinomas; an AERIO/UNICANCER Study

Background: Trials have shown benefit of adjuvant trastuzumab (TZM) for node-positive (N+) or T1c+ HER2−positive breast carcinomas.

Methods: Retrospective series in 6 french cancer centers from 2000 to 2010 of T1abN0M0 HER2 positive breast carcinomas. Multifocal tumors were excluded.

Results: Two hundred five N- cases were retrieved. Median size was 8 mm (range, 2 to 10 mm), 51 were T1a (25%), 152 tumors were T1b; 120 tumors (59 %) exhibited significant hormonal receptors (HR) expression. All patients had surgery, 65 % (n= 133) had a local irradiation. Ninety percent of HR+ patients (108/120) received hormonotherapy: 77 received aromatase inhibitors (AI) upfront or sequential; 23 received tamoxifen (TAM) alone 13 received LHRH agonists alone or in combination with TAM or AI. Forty-nine percent (n= 101) had chemotherapy (CT) (Anthracycline alone for 41 cases, taxane alone for 31 cases, sequential A/T for 28 cases and concurrent for 1 case), associated with TZM in 90 cases. TZM was administered without chemotherapy in 3 cases. Decision of adjuvant CT and/or TZM was associated with (all p&lt;0.05) HR-negative status, Elston-Ellis grade 2/3 and high mitotic index (MI) while patients with HR+/ low MI tumors were rarely treated (p&lt;0.01). With a 41 months median follow-up, there was a statistically significant difference in invasive recurrences between TZM treated patients and others (log-rank test p=0.04). Twelve of the 112 patients treated without TZM (11%) had a recurrent invasive disease including 6 metastatic cases and 3 fatal events. There was one invasive recurrence in TZM group. There were as much recurrences in T1a as in T1b tumors. Three of the 12 recurrences (25%) in the group without TZM occurred in T1a cases.

Conclusion: T1abN0M0 HER2 positive tumors have a significant risk of recurrence which could be avoided by adjuvant chemotherapy associated with TZM. Interestingly, there were no differences in the risk of recurrence between T1a and T1b. Adjuvant chemotherapy associated with TZM should not only be discussed in T1bN0 HER2−positive tumors but also in T1aN0 HER2−positive cases.

Citation Information: Cancer Res 2011;71(24 Suppl):Abstract nr P2-18-03.