Abstract P5-06-31: Morphological apocrine and mucinous features of breast carcinoma: Does histology matter for survival?
Authors: Wang Changjun , Song Yu , Zhu Hanjiang , Zhou Yidong , Mao Feng , Lin Yan , Zhang Yanna , Zhang Xiaohui , Shen Songjie , Zhong Ying , Huang Xin , Sun Qiang 
Published: March 2020

Abstract
Background: Apocrine carcinoma was a rare subtype of breast cancer. Due to its rarity and lack of standardized diagnostic criteria, there was no consensus on its biological behaviors. The present study retrospectively analyzed the Surveillance, Epidemiology, and End Results (SEER) database to clarify the impact of apocrine feature on breast cancer prognosis.
Materials and Methods: Patient data for invasive apocrine (aBC), mucinous (mBC) or ductal (IDC) breast cancer between 2010 and 2012 were obtained from SEER program. Kaplan-Meier method and Cox proportion hazard regression were adopted for breast cancer-specific survival (BCSS) and overall survival (OS) analyses.
Results: There were totally 306 aBC, 2733 mBC and 120127 IDC enrolled. Compared with IDC, aBC tended to occur in elderly patients with higher histological grade, more triple-negative breast cancer (TNBC) and less radiation therapy. Except univariate analysis revealed aBC had shortened BCSS than mBC (HR 5.020, p&lt; 0.001), neither mBC nor IDC revealed BCSS or OS advantage over aBC. As for TNBC, aBC was associated with prolonged BCSS (univariate: HR 0.329, p = 0.020; multivariate: HR 0.183, p = 0.017) and OS (univariate: HR 0.445, p = 0.028; multivariate: HR 0.338, p = 0.016) over IDC. This finding was consistent with the results for hormone receptor negative breast cancers.
Conclusion: aBC had the trend with worse BCSS than mBC and comparable prognosis as IDC. Morphological apocrine features indicated favorable prognosis for TNBC and hormone receptor negative subtype. Future studies were warranted to further evaluate the prognostic value of different histological types.
Table 1. Clinicopathological characteristics of patients with aBC and IDCCharacteristicsaBC (N=306)IDC (N=120127)p value cMedian Follow-up (months)(IQR)22.0 (10.0-35.8)21.0 (10.0-33.0)Age (Mean ± SD)60.7 ± 11.357.8 ± 11.8&lt; 0.001RaceWhite225 (73.8%)93483 (78.3%)0.108Black39 (12.8%)13690 (11.5%)Others a41(13.4%)12145 (10.2%)Marital StatusMarried166 (57.2%)70109 (61.4%)0.164Not Married b124 (42.8%)44086 (38.6%)LateralityLeft136 (44.4%)60705 (50.5%)0.038Right170 (55.6%)59410 (49.5%)GradeI19 (6.4%)24345 (20.8%)&lt; 0.001II159 (53.9%)48323 (41.3%)III / IV117 (39.7%)44294 (37.9%)AJCC StageI154 (50.3%)64223 (53.5%)0.334II109 (35.6%)41978 (34.9%)III43 (14.1%)13926 (11.6%)T StageT1187 (61.1%)75070 (62.5%)0.358T289 (29.1%)36385 (30.3%)T319 (6.2%)5755 (4.8%)T411 (3.6%)2917 (2.4%)N StageN0202 (66.0%)81605 (68.0%)0.589N173 (23.9%)28830 (24.0%)N220 (6.5%)6413 (5.3%)N311 (3.6%)3228 (2.7%)Molecular SubtypeHER2-/ER+62 (20.3%)83840 (69.8%)0.001HER2+/ER+27 (8.8%)14194 (11.8%)HER2+/ER-54 (17.6%)6331 (5.3%)Triple Negative163 (53.3%)15762 (13.1%)SurgeryBCS156 (53.1%)67965 (58.5%)0.067Mastectomy138 (46.9%)48214 (41.5%)RadiationYes139 (48.4%)64981 (56.4%)0.008No148 (51.6%)50270 (43.6%)
Table 2. Clinicopathological characteristics of patients with aBC and mBCCharacteristicsaBC (N=306)mBC (N=2733)p value cMedian Follow-up (months)(IQR)22.0 (10.0-35.8)21.0 (9.0-34.0)Age (Mean ± SD)60.7 ± 11.362.5 ± 12.30.018RaceWhite225 (73.8%)2050 (75.5%)0.709Black39 (12.8%)342 (12.6%)Others a41(13.4%)322 (11.9%)Marital StatusMarried166 (57.2%)1454 (56.1%)0.756Not Married b124 (42.8%)1138 (43.9%)LateralityLeft136 (44.4%)1397 (51.1%)0.031Right170 (55.6%)1335 (48.9%)GradeI19 (6.4%)1538 (60.7%)&lt; 0.001II159 (53.9%)887 (35.0%)III / IV117 (39.7%)110 (4.3%)AJCC StageI154 (50.3%)1773 (64.9%)&lt; 0.001II109 (35.6%)851 (31.1%)III43 (14.1%)109 (4.0%)T StageT1187 (61.1%)1825 (66.8%)0.002T289 (29.1%)741 (27.1%)T319 (6.2%)136 (5.0%)T411 (3.6%)31 (1.1%)N StageN0202 (66.0%)2465 (90.2%)&lt; 0.001N173 (23.9%)221 (8.1%)N220 (6.5%)33 (1.2%)N311 (3.6%)14 (0.5%)Molecular SubtypeHER2-/ER+62 (20.3%)2544 (93.1%)&lt; 0.001HER2+/ER+27 (8.8%)22 (0.8%)HER2+/ER-54 (17.6%)151 (5.5%)Triple Negative163 (53.3%)16 (0.6%)SurgeryBCS156 (53.1%)1769 (66.3%)&lt; 0.001Mastectomy138 (46.9%)898 (33.7%)RadiationYes139 (48.4%)1473 (55.1%)0.037No148 (51.6%)1201 (44.9%)
Table 3. Comparison of BCSS and OS between aBC and IDC by multivariate Cox proportional hazard model according to different molecular subtypesUnivariateMultivariateHazard ratio (95% CI)ap valuebHazard ratio (95% CI)ap valuebAll BCSS1.224 (0.611 - 2.450)0.5680.726 (0.180 - 2.933)0.652OS1.100 (0.624 - 1.939)0.7420.394 (0.098 - 1.585)0.190ER+BCSS2.773 (0.893 - 8.609)0.0661.764 (0.440 - 7.092)0.423OS1.358 (0.438 - 4.214)0.5951.012 (0.253 - 4.049)0.987ER-BCSS0.378 (0.157 - 0.910)0.0240.241 (0.077 - 0.751)0.014OS0.517 (0.268 - 0.995)0.0440.409 (0.194 - 0.864)0.019ER+/HER2-BCSS3.961 (1.275 - 12.30)0.0102.370 (0.590 - 9.524)0.224OS1.912 (0.616 - 5.932)0.2541.370 (0.342 - 5.495)0.656ER+/HER2+ cBCSSNANANANAOSNANANANAER-/HER2+BCSS0.601 (0.084 - 4.287)0.6080.840 (0.117 - 6.061)0.862OS0.854 (0.213 - 3.431)0.8241.120 (0.277 - 4.525)0.874TNBCBCSS0.329 (0.123 - 0.880)0.0200.183 (0.046 - 0.736)0.017OS0.445 (0.212 - 0.935)0.0280.338 (0.140 - 0.816)0.016
Table 4. Comparison of BCSS and OS between aBC and mBC by multivariate Cox proportional hazard model according to different molecular subtypesUnivariateMultivariateHazard ratio (95% CI)ap valuebHazard ratio (95% CI)ap valuebAll BCSS5.020 (2.106 - 11.97)&lt;0.0011.517 (0.211 - 10.78)0.679OS1.361 (0.741 - 2.498)0.3190.400 (0.090 - 1.779)0.229ER+BCSS7.258 (2.067 - 25.48)&lt;0.0012.193 (0.478 - 10.10)0.312OS1.226 (0.387 - 3.888)0.7290.822 (0.201 - 3.356)0.785ER-BCSS0.877 (0.102 - 7.507)0.9040.289 (0.030 - 2.809)0.285OS0.791 (0.171 - 3.659)0.7630.354 (0.073 - 1.721)0.198ER+/HER2-BCSS14.03 (3.793 - 51.86)&lt;0.0013.788 (0.782 - 18.52)0.098OS1.731 (0.545 - 5.495)0.3461.098 (0.268 - 4.505)0.897ER+/HER2+ cBCSSNANANANAOSNANANANAER-/HER2+ cBCSSNANANANAOSNANANANATNBCBCSS0.374 (0.042 - 3.352)0.3600.183 (0.016 - 2.049)0.168OS0.339 (0.070 - 1.634)0.1580.224 (0.043 - 1.170)0.076
Citation Format: Changjun Wang, Yu Song, Hanjiang Zhu, Yidong Zhou, Feng Mao, Yan Lin, Yanna Zhang, Xiaohui Zhang, Songjie Shen, Ying Zhong, Xin Huang, Qiang Sun. Morphological apocrine and mucinous features of breast carcinoma: Does histology matter for survival? [abstract]. In: Proceedings of the 2019 San Antonio Breast Cancer Symposium; 2019 Dec 10-14; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2020;80(4 Suppl):Abstract nr P5-06-31.