Abstract PD09-05: Single nucleotide polymorphism of XRCC1 which participates in DNA repair mechanism predicts clinical outcome in relapsed or metastatic breast cancer patients treated with S1 and oxaliplatin chemotherapy: Results from multicenter prospective study (TORCH_KCSG BR07-03)

Background: S1 and oxaliplatin (SOX) combination chemotherapy is an effective regimen in anthracycline and taxane pretreated metastatic breast cancer (MBC) patients with manageable toxicities (KCSG BR07-03, SABCS 2011 #Abst P3-16-06). The aim of this study was to investigate the association of the single nucleotide polymorphisms (SNPs) and clinical outcome in MBC treated with SOX chemotherapy.

Patients and Methods: A total of 87 MBC patients previously treated with or resistant to anthracycline and taxane chemotherapy were enrolled in this prospective multicenter trial. The patients received S-1 80mg/m2/day (day 1–14) and oxaliplatin 130 mg/m2 (day 1) every 3 weeks till progression. Among the 87 patients, 77 patients were available for SNP analysis. Germline DNA from peripheral blood (PB) mononuclear cells was extracted. SNPs in 4 genes from pathways that may influence cellular sensitivity to S1 and oxaliplatin (TS, ERCC, XPD, and XRCC) were genotyped from PB sample using PCR-restriction fragment length polymorphism.

Results: Overall response rate (RR) was 38.5% (95% CI: 27.7–49.3) and disease control rate was 67.9% (95% CI:57.5–78.3) to SOX. Median time-to-progression (TTP) and overall survival (OS) were 6.0 mo (95% CI: 5.1–6.9 mo) and 19.4 mo (95% CI: not estimated), respectively. XRCC1 Arg194Trp SNP which participates in DNA repair mechanism showed correlation with the clinical outcome. RR was tend to higher in XRCC1 Arg194Trp CC genotype compared with CT or TT genotype (50.0 % vs 35.1% or 12.5%, P = 0.121). TTP of patients with CC genotype in XRCC1 Arg194Trp was significantly longer than the TTP of patients with CT or TT genotype (median TTP: 6.4 mo in CC, 5.9 mo in CT, 3.0 mo in TT, P = 0.007) as well as overall survival (OS) (median OS: not reached in CC, 13.9 mo in CT, 7.1 mo in TT, P = 0.006). After adjusting for hormone receptor status, performance status, and visceral involvement, prognostic value of XRCC1 Arg194Trp SNP remained significant (Hazard Ratio=1.322 and 4.484, P = 0.016). Other SNPs were not significantly associated with survival or toxicities.

Conclusion: XRCC1 Arg194Trp SNP is associated with clinical outcome of MBC patients treated with SOX chemotherapy. Further studies of the relationship between germline polymorphisms in XRCC1 and functional mechanism researches are warranted.

Citation Information: Cancer Res 2012;72(24 Suppl):Abstract nr PD09-05.

Brain metastases in Asian HER2-positive breast cancer patients: anti-HER2 treatments and their impact on survival

BACKGROUND

In Asia, large-scale studies on anti-HER2 treatment in HER2-positive breast cancer patients with brain metastases are limited. We studied the treatment patterns of these patients in Asia to evaluate the impact of anti-HER2 treatment on the time to occurrence of brain metastases (TTBM) and survival after brain metastasis (BM).

METHODS

A retrospective study of HER2-positive breast cancer patients diagnosed with BM between January 2006 and December 2008 in six Asian countries was conducted. Demographics, tumour characteristics, treatment details, and events dates were collected from medical records.

RESULTS

Data from 280 patients were analysed. Before BM, 63% received anti-HER2 treatment. These patients had significantly longer TTBM than those without anti-HER2 treatment (median 33 vs 19 months; P<0.002). After BM, 93% received radiotherapy, 57% received chemotherapy, and 41% received anti-HER2 treatment (trastuzumab and/or lapatinib). Use of both anti-HER2 agents, primarily sequentially, after BM demonstrated the longest survival after BM and was associated with a significant survival benefit over no anti-HER2 treatment (median 26 vs 6 months; hazard ratio 0.37; 95% CI 0.19-0.72).

CONCLUSION

Anti-HER2 treatment before BM was associated with longer TTBM. Anti-HER2 treatment after BM was associated with a survival benefit, especially when both trastuzumab and lapatinib were utilised.

Resumption or persistence of menstruation after cytotoxic chemotherapy is a prognostic factor for poor disease-free survival in premenopausal patients with early breast cancer

BACKGROUND

We investigated the relationship between resumption or persistence of menstruation after cytotoxic chemotherapy (RM) and disease-free survival (DFS) in premenopausal patients with early breast cancer.

METHODS

Medical records from 872 patients who received cytotoxic chemotherapy for stage I to III breast cancer were retrospectively reviewed.

RESULTS

The median patient age was 41 years (range, 21-54) and the median follow-up duration was 6.2 years (range, 0.7-10.4). Six hundred ninety-two patients (79.4%) were hormone receptor (HR) positive and the majority of these received tamoxifen therapy after completing chemotherapy. The chemotherapy-induced amenorrhea (CIA) rate was 76.7% (n = 669), and 51.8% (n = 452) experienced RM during the follow-up period. One hundred twenty-one (13.9%) patients had persistent menstruation without CIA. DFS was significantly affected by younger age at diagnosis (≤35 years) (P = 0.013), tumor size > 2 cm (P < 0.001), node positivity (P < 0.001), HR negativity (P < 0.001), HER2 positivity (P = 0.010), and RM (P < 0.001). HR negativity [hazard ratio 1.7, 95% confidence interval (CI) 1.2-2.4, P = 0.006], tumor size > 2 cm (hazard ratio 2.1, 95% CI 1.4-3.0, P < 0.001), node positivity (hazard ratio 3.0, 95% CI 2.0-4.7, P < 0.001), and RM (hazard ratio 1.8, 95% CI 1.2-2.7, P = 0.004) remained significant factors for DFS on multivariate analysis.

CONCLUSIONS

A considerable proportion of premenopausal patients treated with chemotherapy experienced RM after CIA. RM was a poor prognostic factor for DFS in premenopausal patients with early breast cancer.

P4-01-13: Biology of Aggressiveness and Tamoxifen Resistance in Hormone Receptor-Positive Very Young Age Breast Cancer

It has been known that young breast cancer patients have worse outcomes compared with older premenopausal or postmenopausal patients. Survival difference between young and older breast cancer patients is evident only in hormone receptor positive breast cancer regardless of tamoxifen treatment according to our previous report. However, the biology of aggressiveness and endocrine resistance of breast cancer in very young women is largely unknown. The purpose of this study is to find molecular characteristics of hormone receptor positive breast cancers of very young age women (&lt;35) compared with those of older premenopausal women.

We extracted mRNA from fresh frozen hormone receptor positive primary breast cancer tissues of 24 young age breast cancer patients (&lt;35 years) and 31 older premenopausal women (40 to 49 years) by standard method. All tumor specimens analyzed contained more than 50% tumor cells. Hormone receptor status was determined by immunohistochemistry (IHC). Gene expression microarray experiment was done in the 55 samples using Illumina HumanRef-8 v3 Expression BeadChip (Illumina, Inc., San Diego, CA). Functional and pathway analysis of differentially expressed genes were done using DAVID (http://david.abcc.ncifcrf.gov/home.jsp) and Ingenuity pathway analysis (IPA, http://www.ingenuity.com). Ki-67 assay was done using IHC in 4,957 ER+ breast cancer patients of Seoul National University cohort and 1,863 ER+ patients from National Cancer Center, Korea.

355 genes were upregulated (&gt;1.5 fold) and 209 genes were down-regulated in breast cancer tissues of young age patients (&lt;35) compared with those of older patients. In pathway analysis of the highly expressed genes in young patients, cell cycle function and pathway was significantly activated. The genes of central role in this pathway were MYC and CCND1. In IHC assay for 4,957 ER+ Seoul National University dataset, the proportion of high Ki-67 expression (&gt;=10%) was positively correlated with decreasing age: 26.4%, 24.0%, 21.3%, 14.8%, 12.0% of women aged &lt;30, 30–34, 35–39, 40–49, 50–59, respectively (p&lt;0.001). The same correlation pattern between younger age and high Ki-67 expression was also seen in another 1,863 patient cohort.

In conclusion, we showed that genes involved in cell cycle pathway were upregulated in very young age (&lt;35) ER+ breast cancer using microarray study. It was validated in large data set using Ki-67 IHC assay. High proliferation and fast cell cycle could be a mechanism of worse outcome and tamoxifen resistance of ER+ very young age breast cancer patients.

Citation Information: Cancer Res 2011;71(24 Suppl):Abstract nr P4-01-13.

P3-16-06: Phase II Trial of TS-1 in Combination with Oxaliplatin (SOX) in Patients with Metastatic Breast Cancer (MBC) Previously Treated with Anthracycline and Taxane Chemotherapy [TORCH] [Korean Cancer Study Group (KCSG) BR07-03]

Background

Oxaliplatin, a platinum analogue, is an active drug in advanced anthracycline and taxane-pretreated breast cancer patients as a single agent and with 5-fluorouracil (5-FU) combination. TS-1 was developed by the scientific theory of both potentiating antitumor activity of 5-FU and reducing gastrointestinal toxicity. This trial was performed to evaluate the efficacy and safety of TS-1 in combination with oxaliplatin in metastatic breast cancer (MBC) patients previously treated with anthracycline and taxane chemotherapy.

Methods: Between October 2007 and October 2009, MBC patients were enrolled in this prospective multicenter trial. Eligible criteria included age ≥18 years, at least one measurable lesion, prior treatment with anthracycline and taxane chemotherapy, and ECOG Performance Status 0–2. TS-1 40 mg/m2 b.i.d. on days 1–14 with oxaliplatin 130 mg/m2 on day 1 were administered every 3 weeks till disease progression. Primary end-point was response rate, and secondary end-points were time-to-progression (TTP), overall survival (OS), duration of response (DOR) and toxicities. Response was evaluated every 6 weeks according to the RECIST criteria v. 1.0 and toxicity was assessed with NCICTCAE v.3.0.(ClinicalTrials.gov identifier NCT00527930).

Results: A total of 87 patients were enrolled. Median age was 48 years (range 30–71 years). Nineteen patients (21.8%) had de novo stage IV and 68 patients (78.2%) had recurrent disease. Thirty-five patients (40.2%) received two-lines of prior chemotherapy in palliative setting. Forty-eight patients (55.2%) had ≥ 3 disease sites. Fifty-four patients (62.1%) were hormone receptor positive, and 25 patients (28.7%) were triple negative. Five patients received prior anti-HER2 therapy. A total of 525 cycles were administered (median 6 cycles, range: 1 ∼ 22+ cycle). In per-protocol analysis, overall response rate was 38.5% (95% CI: 27.7−49.3) (CR 0%, PR 38.5%) and disease control rate (CR, PR, and SD) was 67.9% (95% CI: 57.5−78.3). Median TTP, OS, and DOR were 6.0 months (95% CI: 5.1−6.9 months), 19.4 months (95% CI: not estimated), 6.6 months (95% CI: 3.7−9.6 months), respectively. RR was not different by triple negativity (39.1% in TNBC vs. 38.2% in non-TNBC, P=0.361). TTP was not different according to the number of prior chemotherapy regimens. Reported grade 3 or 4 toxicities (per cycle) were neutropenia (10.3%), thrombocytopenia (5.5%), diarrhea (1.9%), vomiting (1.9%), and stomatitis (0.2%). There was no treatment-related death.

Conclusions: SOX is an effective regimen in anthracycline and taxane pretreated MBC patients with manageable toxicities.

Citation Information: Cancer Res 2011;71(24 Suppl):Abstract nr P3-16-06.

P4-17-12: Analysis of Predictive and Prognostic Factors for Metastatic Breast Cancer Patients with Brain Metastasis Treated by Whole Brain Radiotherapy

Background We addressed the progression free survival of brain metastasis (PFS_BM) in metastatic breast cancer (MBC) patients treated by whole brain radiotherapy (WBRT) for brain metastasis (BM). In addition, we investigated predictive and prognostic factors for the PFS_BM and OS_BM.

Patients and methods A total of 212 patients with BM, treated by WBRT at the National Cancer Center between January 2000 and December 2010 were reviewed. The PFS_BM was defined as the time interval from the date of start of WBRT to the date of a progression of metastatic lesions in the brain or death or last follow-up.

Results The median age of patients was 45 years (range, 22–72 years) and the median time to brain metastasis was 12.7 months (range, 0.0−72.8 months).

Abstract P4-09-14: Invasive Lobular Carcinoma Is a Prototype of Luminal A Breast Cancer Subtype and Rare in Korea

Purpose Invasive lobular carcinoma (ILC) is known to be the second most frequent histologic subtype, occupying 10% of invasive breast cancer in the Western countries. The present study was designed to assess the clinical characteristics and outcomes of ILC compared to general invasive ductal carcinoma (IDC) and the luminal A subtype (LA-IDC).

Methods The study population included d 2916 patients with invasive breast cancer consecutively diagnosed at the National Cancer Center, Korea between 2001 and 2008. The clinicopathological characteristics and clinical outcomes were retrospectively reviewed.

Results There were 83 pts (2.8%) diagnosed with ILC and 1,088 pts (37.3%) with LA-IDC. Mean age was 48.2 years of all patients, 48.3 years of ILC group and 47.9 years of LA-IDC group. The ILC patients presented with a larger tumor size (≥T2, 59.8% vs. 38.8%, P=0.001), lower histologic grade (HG 1 or 2, 90.4% vs 64.4%, P&lt;0.001), more often estrogen receptor (ER) and progesterone receptor (PgR) positivity (ER+, 90.4% vs. 64.4%, P&lt;0.001; PgR+, 71.1% vs. 50.1%, P&lt;0.001), HER2 negativity (97.5% vs. 74.9%, P&lt;0.001), lower Ki-67 expression (10.3% ± 10.6% vs. 20.6% ± 19.8%, P&lt;0.001), and luminal A subtypes (91.4% vs. 51.2%, P&lt;0.001) compared to the IDC group. Six (7.2%) ILC patients and 359 (12.7%) IDC patients developed disease recurrence with a median follow-up of 56.4 months (range 4.9-136.6 months). Although ILC showed similar prognosis to IDC in general (5-year DFS rate, 91.7% in ILC vs. 87.4% in IDC, P=0.31; 5-year OS rate, 93.6% in ILC vs. 92.5% in IDC, P=0.38), its outcome was closer to LA-IDC, and better than non LA-IDC (LA-IDC (ref); ILC, HR 0.77 in recurrence, 95% CI 0.31-1.90, P=0.57; HR 0.75 in death, 95% CI 0.18-3.09, P=0.70; non LA-IDC, HR 1.69 in recurrence, 95% CI 1.23-2.33, P=0.001; HR 1.50 in death, 95% CI 0.97-2.33, P=0.07) in univariate and multivariate analysis.

Conclusions ILC is a very rare histologic subtype of breast cancer in Korea compared to the Western countries and has distinctive clinicopathological characteristics similar to those of LA-IDC. Acknowledgement: supported by NCC grant #0910320

Citation Information: Cancer Res 2010;70(24 Suppl):Abstract nr P4-09-14.

Abstract P1-14-04: Clinical Outcomes of Brain Metastasis by Lapatinib (L) and Capecitabine (C) in an Open-Label Expanded Access Study among Korean Patients with HER2 Positive Metastatic Breast Cancer

Background: The L-Expanded Access Program (LEAP) was designed to provide access to L/C for HER2+ patients (pts) who previously received anthracycline, taxane, and trastuzumab. In earlier registration trial, CNS metastases occurred in fewer women receiving L/C therapy compared with C alone. Although L therapy has shown efficacy in brain metastasis (BM), it has not been well elucidated in relationship with the outcomes of systemic disease.

Patients and methods : Enrollment in LEAP lasted between Jan. 2007 and Apr. 2008 at 6 centers in Korea. Exploratory analysis on clinical outcomes of brain metastasis was performed.

Results: Total 187 pts enrolled in LEAP. The median treatment duration of all pts was 19.0 weeks (range, 1.4 — 146.9). The median progression free survival and overall survival (OS) of all pts were 20.0 (95% confidence interval [CI]= 18.6-24.0) and 60.0 (95% CI= 50.3-72.7) weeks, respectively. All patients received prior trastuzumab therapy, and 48.7% received prior capecitabine. Among 58 enrolled pts who had BM diagnosed before start L/C therapy, 55 pts were included for the analysis excluding 3 pts (1-consent withdrawal and 2-&lt;3 weeks trial). Fifteen pts had single BM. Majority were HER2 IHC 3+ or FISH +, and 48% were both ER/PR-. Prior to EAP enrollment, 35 pts underwent whole brain radiation, 10 pts SRS or gamma knife, 3 pts local excision, 1 pt had leptomeningeal disease only receiving intrathecal therapy, and 6 pts did not receive local CNS therapy. Four pts underwent more than one modality of local CNS therapy. Of 50 pts evaluable for response, 9.1%, achieved or remained CR; 45.5% had some degree of shrinkage of BM; 14.5%, no change (SD) ≥6mo; 7.3%, SD &lt;6mo; 14.5% developed PD or recurrence of BM. Median TTP of pts (n=53) with BM on L/C therapy was 30.7 weeks (95% CI=25.0-35.1) and median OS (n=55) was 53.1 weeks (95% CI= 42.3-78.0). From the multivariate analysis, TTP of BM was significantly associated with response of BM (HR, 20.3, 95% CI=7.3-56.0, P&lt;0.001). OS of pts with BM was significantly longer with tumors of ER or PR+ status (HR, 3.10, 95% CI=1.55-6.19, p=0.0014), and who responded in systemic disease and brain (HR, 4.5, 95% CI= 2.2-9.2, P&lt;0.0001). Of remaining 129 pts, 8 pts (6.2%) developed new BM on EAP.

Conclusion: Overall survival of patients with brain metastasis who received lapatinib plus capecitabine was prolonged specifically in responders of both brain and extracranial disease. Patients with hormone receptor positive tumors had longer survival compared with those of hormone receptor negative disease.

Citation Information: Cancer Res 2010;70(24 Suppl):Abstract nr P1-14-04.

Abstract P2-09-01: Serial [18F] FDG-PET after the 2nd Cycle of Preoperative Chemotherapy Is Predictive for Pathological Complete Response in Stage II/III Breast Cancer

Purpose: One of substudies of the prospective trials aimed to evaluate the usefulness of serial [18F] 2-fluoro-2-deoxy-D-glucose-positron emission tomography ([18F] FDG-PET) for predicting pathological complete response (pCR) in stage II/III breast cancer with preoperative chemotherapy (PST).

Methods: Serial PET was undertaken in 57 breast cancer patients enrolled in three different neoadjuvant trials: 35 patients from a phase II study with paclitaxel/gemcitabine/trastuzumab with ClinicalTrial.gov NCT 00532857, 9 patients from a phase Ib study with paclitaxel/gemcitabine/lapatinib with ClinicalTrial.gov NCT 01133912, and 13 patients from a phase Ib with paclitaxel/gemcitabine/sunitinib with ClinicalTrial.gov NCT0 1070706. All patients received 6 cycles of PST followed by surgery and radiotherapy. We assessed the peak standardized uptake value (SUVp) in the primary tumor at the baseline and after the 2nd cycle (37 patients) or after completion (20 patients) of 6 cycles of PST, and calculated the reduction rate (RR) of the SUVp. Pathological response was classified into pCR and non-pCR. To compare the mean of SUVp and RR of SUVp between different response groups, two-way tables and chi-square tests were used

Results: Fifteen (40.6%) of 37 patients who took repeat PET after the 2nd PST and 15 (75%) of 20 patients after completion of PST achieved a pCR with overall pCR rate of 52.6% in the primary tumor. In patients with repeat PET after the 2nd PST, post-treatment SUVp and RR of the SUVp in primary tumors were significantly different by the pathological response (post-treatment SUVp, 1.54 ± 0.63 in pCR vs 2.54 ± 1.06 in non-pCR, P=0.002; RR of the SUVp, 79.2% ± 11.9% in pCR vs 68.9% ± 15.4% in non-pCR, P=0.03). However, in patients with repeat PET after completion of PST, there were no statistical differences of these values (post-treatment SUVp, 1.09 ± 0.63 in pCR vs 1.29 ± 0.36 in non-pCR, P=0.42; RR of the SUVp, 83.7% ± 14.0% in pCR vs 67.5% ± 21.1% in non-pCR, P=0.17)

Conclusions: This study demonstrated that repeat PET after the 2nd cycle of PST, not after completion of PST could predict pCR in stage II/III breast cancer with preoperative chemotherapy. Acknowledgement NCC Grant #0910320.

Citation Information: Cancer Res 2010;70(24 Suppl):Abstract nr P2-09-01.

Effect of dietary soy intake on breast cancer risk according to menopause and hormone receptor status

BACKGROUND

Although high soy consumption may be associated with lower breast cancer risk in Asian populations, findings from epidemiological studies have been inconsistent.

OBJECTIVE

We investigated the effects of soy intake on breast cancer risk among Korean women according to their menopausal and hormone receptor status.

METHODS

We conducted a case-control study with 358 incident breast cancer patients and 360 age-matched controls with no history of malignant neoplasm. Dietary consumption of soy products was examined using a 103-item food frequency questionnaire.

RESULTS

The estimated mean intakes of total soy and isoflavones from this study population were 76.5 g per day and 15.0 mg per day, respectively. Using a multivariate logistic regression model, we found a significant inverse association between soy intake and breast cancer risk, with a dose-response relationship (odds ratios (OR) (95% confidence interval (CI)) for the highest vs the lowest intake quartile: 0.36 (0.20-0.64)). When the data were stratified by menopausal status, the protective effect was observed only among postmenopausal women (OR (95% CI) for the highest vs the lowest intake quartile: 0.08 (0.03-0.22)). The association between soy and breast cancer risk did not differ according to estrogen receptor (ER)/progesterone receptor (PR) status, but the estimated intake of soy isoflavones showed an inverse association only among postmenopausal women with ER+/PR+ tumors.

CONCLUSIONS

Our findings suggest that high consumption of soy might be related to lower risk of breast cancer and that the effect of soy intake could vary depending on several factors.

Significance of Viral Reactivation in Hepatitis B Virus Carriers with Early Breast Cancer Receiving Anthracycline- or Taxane-Containing Chemotherapy

Background :It is known that cancer patients in healthy hepatitis B viral (HBV) carrier status are prone to develop hepatic dysfunction during cytotoxic chemotherapy. The objectives of this study were to determine the frequency of healthy HBV carrier status and subsequent viral reactivation resulting in hepatic dysfunction during cytotoxic chemotherapy, and its significance in early breast cancer patients.Methods :Among 3,433 patients with operable breast cancer diagnosed at the National Cancer Center, Korea between January 2001 and March 2009, 3,337 patients were tested for HBsAg. Retrospectively, medical records were reviewed for 139 (4.2%) patients who were positive for HBs Ag.Results :Of 139 patients, 112 patients received anthracycline or taxane based neoadjuvant (n=25) or adjuvant (n=87) combination chemotherapy. Prophylactic lamivudine therapy was administered in 33 patients (29.5%).Thirty of 112 (26.8%) patients developed reactivation of HBV with deterioration of hepatic function during chemotherapy. The rate of reactivaton was not different with or without further taxane therapy (43% vs. 44%, p=0.408).Although there was no significant difference in the rate of chemotherapy delay between two groups, the incidence of early termination of planned chemotherapy was higher in B viral reactivation group (23.3% vs. 4.9%, p=0.008). Within a median follow-up duration of 39 mo (range 1 mo to 95 mo), the rate of disease recurrence was comparable between two groups (10% vs. 18.3%, p=0.390).Lamivudine prophylaxis decreased the rate of HBV reactivation without statistical significance (15.1% vs. 35.4%, p=0.101). Despite more patients without prophylaxis developed G 3/4 AST/ALT elevation (40% vs. 84%, p=0.068), the majority of patients recovered to G 1/2 AST/ALT level within 12 months with anti-viral or supportive treatment (0% vs. 14.3%, p=1.00). One patient without lamivudine prophylaxis developed fulminant hepatic failure after 3rd cycles of neo-adjuvant chemotherapy and received living donor liver transplantation. After that, she received radical mastectomy and maintained adjuvant anti-hormonal therapy.Conclusions :Although lamivudine prophylaxis in HBV healthy carrier decreased the rate of viral reactivation during neo- or adjuvant chemotherapy, the majority of patients irrespective of prophylaxis recovered hepatic function in a year with conservative treatment. Early detection and intensive supportive care are as important as anti-viral prophylaxis in HBV healthy carrier when treated with cytotoxic chemotherapy.

Citation Information: Cancer Res 2009;69(24 Suppl):Abstract nr 1113.

Prognostic Factors for Locoregional Recurrence in Operable Breast Cancer Patients Treated with Preoperative Systemic Chemotherapy

Background: We aimed to evaluate the clinicopathologic factors affecting locoregional recurrence (LRR) in potentially operable breast cancer patients receiving preoperative systemic chemotherapy (PST).Methods: We reviewed the records of 316 breast cancer patients treated with PST (doxorubicin/cyclophosphamide, 101; docetaxel /capecitabine, 103; paclitaxel/gemcitabine, 43; doxorubicin/docetaxel, 69) followed by surgery and adjuvant radiotherapy between 2002 and 2006. The majority of patients had clinical positive axillary lymph nodes. To define the prognostic factors for LRR, age, clinical stage, hormone receptor (HR) and HER2 status, clinical and pathologic response, type of operation, pathological characteristics including tumor size, tumor grade, nodal status, number of positive axillary nodes, size of metastatic lymph node and status of resection margin and tumor multiplicity before and after PST were analyzed.Results: Overall 52 patients (16.5%) in the primary tumor and 87 patients (27.5%) in the axillary nodes achieved a pathologic complete response (pCR), and 206 patients (65.2%) underwent breast conserving surgery (BCS). With a median follow-up of 52.4 month (range: 4.7 - 89.4), total 18 (5.7%) patients developed LRR; 2 of 110 (1.8%) patients with mastectomy vs. 16 of 206 (7.7%) patients with BCS (p=0.04). Other significant factors in the univariate analysis were clinical T stage, HR status, clinical response and tumor multiplicity. A pCR in the primary tumor or node was not a prognostic factor for LRR in this study. In multivariate analysis, clinical T stage (T3/4, HR 7.8; 95% CI, 2.33-26.24; P=0.001), hormone receptor status (negative, HR 6.2; 95% CI, 1.91-20.22; P=0.002) and type of surgery (BCS, HR 9.5; 95% CI, 1.97-46.37; P=0.005) were independent prognostic factors. Among patients with BCS, advanced clinical T stage (HR 12.4; 95% CI, 3.45-44.56; P&lt;0.001), negative hormone receptor (HR 4.74; 95% CI, 1.33-16.96; P=0.02), non-responding disease (HR 6.54; 95% CI, 1.07-40.12; P=0.04) and multiple tumors (HR 4.36; 95% CI, 1.06-17.90; P=0.04) developed more frequent LRR.Conclusions: Significantly more patients with advanced clinical T stage, negative HR status and BCS developed LRR in operable breast cancer treated with PST. Moreover, in patients with BCS after PST, clinically non-responding disease and multiple tumors showed unfavorable prognosis besides the larger tumors and negative hormone receptor.Partly supported by NCC Grant No 0610240

Citation Information: Cancer Res 2009;69(24 Suppl):Abstract nr 1095.