Background: Breast cancer is the most common cancer in women, and postoperative breast pain has been reported to be anywhere from 25% to 60%. However, there is sparse data regarding racial/ethnic differences in breast pain among breast cancer patients. Methods: We performed a cross-sectional anonymous survey of breast cancer patients from the Hawaii Cancer Consortium over a 6-week period between 2019 and 2020. The 237 breast cancer participants were ages 29 to 98, 74% Asian, and mainly from outpatient oncology clinics. We evaluated the prevalence of breast pain in a diverse group of breast cancer patients and characterized the pain using a modified short-form McGill pain questionnaire (sfMPQ). Results: Eighty-fourrespondents(35.4%) reported breast pain. On univariable analysis, we found significant racial/ethnic differences in the amount of breast pain, where Chinese and Japanese participants reported significantly less pain compared to White participants on a 10-point pain scale. We found differences in breast pain according to age and endocrine therapy use as well as survey location, however, no differences were seen according to chemotherapy, radiation, or breast surgery. Based on the sfMPQ, the most common descriptors of breast pain were sensory (throbbing, shooting, and stabbing) compared to affective (tiring-exhausting, sickening, fearful, and punishing-cruel) characteristics. Although they were described as mild and intermittent, in women with breast pain, 33.4% reported the breast pain affected their sleep, 16.7% their work, and 15.4% their sexual activity. Conclusions: Breast pain is a significant problem in our breast cancer community. This survey assessment has informed our understanding of breast pain in our diverse population. In turn, we are developing culturally appropriate pain management strategies to treat this challenging symptom common in breast cancer survivors.

Background/Rationale: There have been increasing studies regarding the morphologic evaluation of tumor-infiltrating lymphocytes (TILs) and the tumor microenvironment. In breast cancer, TILs are more abundant in stroma (sTILs) compared to intratumoral (iTILs) areas and iTILs have been an unreliable marker due to difficulty in standardizing their evaluation. The International Immuno-Oncology Working Group published recommendations to guide the accurate assessment of TILs. TILs have relevance in the setting of neoadjuvant therapy (NAT), primarily in triple negative and HER2 positive breast cancers. Studies report that sTIL infiltration is predictive of response to NAT in these two breast cancer subtypes, but not in the estrogen positive breast cancer subtype. The presence of TILs is a good prognostic indicator and correlates with axillary lymph node negativity, lower histological grade and improved recurrence-free survival. Therefore, evaluating TILs prior to NAT can provide important predictive and prognostic information for clinicians. There are insufficient data exploring differences in sTILs among different racial/ethnic groups. Previous data showed Asians had more sTILs compared to White and African American patients, consistent with data from Asia that found substantial sTILs in their respective patient populations. Our diverse population has known racial/ethnic disparities, where Pacific Islanders have a higher mortality compared to Asian and White patients. Evaluating sTILs within this population may reveal tumor biology differences that could contribute to health disparities. Research objectives: To determine the stromal tumor infiltrating lymphocytes on core biopsy specimens and correlate them with clinical characteristics: ethnicity, age, BMI and stage To determine differences in pathologic complete response (pCR) with ethnicity, age, BMI, neoadjuvant therapy and stage Table 1. % Stromal tumor infiltrating lymphocytes (sTILs) compared to age, BMI, ethnicity, stage and pCR adjusted for breast cancer subtypeVariableValueNMeanSDPAge30838.615.140927.123.0.30501834.626.6.67601431.121.3.4570+826.822.8.30BMI< 252825.918.825-301638.521.9.07> 301337.228.0.12EthnicityAsian1636.724.2.01Pacific Islander2038.021.3.004White1818.515.9Other348.130.6.02Stage1A818.48.01B933.425.5.192A1631.923.0.172B938.620.6.113A630.823.2.313B937.225.8.10pCRno3233.019.8yes2530.825.6.72 Table 2. Pathologic complete tesponse (pCR) compared to age, BMI, neoadjuvant therapy, ethnicity and stage adjusted for breast cancer subtypeVariableValueNMeanSDPAge3080.5500.5354090.4060.527.5650180.4450.511.6360140.3030.469.2770+80.5860.518.89BMI< 25280.5260.50825-30160.2730.447.11> 30130.4530.519.65Neoadjuvant TherapyACT140.2680.469.88TC110.2370.505TCHP160.7480.479.02THP120.4280.515.41Letrozole40.3850.500.62EthnicityAsian160.4720.512.77Pacific Islander200.3890.503.85White180.4200.511other30.7060.577.36Stage1A80.2410.3541B90.4270.527.412A160.7240.479.022B90.0320.441.403A60.8220.516.023B90.2680.500.90 Results: We evaluated 57 neoadjuvant breast cancer cases for sTILs according to the International Immuno-Oncology Working Group recommendations and reviewed their clinical characteristics. We found significant % sTILs differences in ethnicity, specifically Asian (35%), Pacific Islander (38.5%) and Other (46%) category compared to White (19%) Table 1. There were no differences found in sTILs according to age, BMI or stage. We also found no significant pCR differences according to age, BMI or ethnicity, however for certain stages and neoadjuvant therapy, there is an increased rate of pCR, although these are a small number of cases, no conclusions can be made, Table 2. Future studies to evaluate the significance of sTILs in different ethnicities may be informative to delineate possible mechanisms contributing to known disparities they experience. Citation Format: Jami Fukui, Alana Taniguchi, Madison Meister, Ian Pagano, Jeffrey Killeen. Racial/ethnic differences in tumor infiltrating lymphocytes [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 P6-06-13.

e24085 Background: Breast cancer is the most common cancer in women. Prevalence rates for persistent pain following breast cancer surgery are reported to be up to 60%. Younger age, radiation, more invasive surgery, and acute post-operative pain have been identified as predictors of chronic pain after surgery. Several studies have looked at factors predicting breast pain, but to our knowledge none of these studies have reported on perceived pain among ethnic groups beyond white and non-white comparisons. Methods: Participants were asked to complete an anonymous breast pain questionnaire based on the McGill pain questionnaire, either online or face-to-face in a clinical setting. Incidence and type of breast pain, common risk factors (age, type of surgery, treatment: chemotherapy, radiation and endocrine therapy), and race/ethnicity was collected and analyzed through descriptive and multivariate analysis. Results: 238 responses were collected and analyzed. About 36% of participants reported breast pain, where 82% reported these symptoms for more than a year. More than 71% identified as non-white, with the majority identifying as Asian (50%) followed by White (11%), Multi-ethnic (9%) and Native Hawaiian (8%). The majority of participants were older than 60 years of age (57%), with 30% being older than 70. Japanese, Filipino and Native Hawaiian participants reported significantly more pain compared to White participants (p < .0001). The majority of participants reported a 3/10 pain level on a pain scale and described overall breast pain as mild. The most common descriptor of mild pain was aching and represents the dullness pain characteristic. The most common descriptor of moderate pain was sharp characterizing an incisive pressure, and the most common descriptors of severe pain were heavy, tender, shooting and throbbing, representing various pain characteristics. Participants who were undergoing radiation (p < .0001) or chemotherapy (p < .05) reported statistically higher breast pain, although there were no differences in breast pain according to the type of surgery (mastectomy vs lumpectomy). Participants who completed the survey online also reported more pain (p < .0001) than participants who completed the survey face-to-face. Conclusions: Breast pain is a significant problem in our breast cancer community. This questionnaire has informed our understanding of the type of pain our multi-ethnic breast cancer patients are experiencing and in turn we are developing culturally appropriate pain management strategies to treat this challenging symptom for breast cancer survivors.