Liposomal Phenylephrine Nanoparticles Enhance the Antitumor Activity of Intratumoral Chemotherapy in a Preclinical Model of Melanoma

Intratumoral injection of anticancer agents has limited efficacy and is not routinely used for most cancers. In this study, we aimed to improve the efficacy of intratumoral chemotherapy using a novel approach comprising peri-tumoral injection of sustained-release liposomal nanoparticles containing phenylephrine, which is a potent vasoconstrictor. Using a preclinical model of melanoma, we have previously shown that systemically administered (intravenous) phenylephrine could transiently shunt blood flow to the tumor at the time of drug delivery, which in turn improved antitumor responses. This approach was called dynamic control of tumor-associated vessels. Herein, we used liposomal phenylephrine nanoparticles as a "local" dynamic control strategy for the B16 melanoma. Local dynamic control was shown to increase the retention and exposure time of tumors to intratumorally injected chemotherapy (melphalan). C57BL/6 mice bearing B16 tumors were treated with intratumoral melphalan and peri-tumoral injection of sustained-release liposomal phenylephrine nanoparticles (i.e., the local dynamic control protocol). These mice had statistically significantly improved antitumor responses compared to melphalan alone (p = 0.0011), whereby 58.3% obtained long-term complete clinical response. Our novel approach of local dynamic control demonstrated significantly enhanced antitumor efficacy and is the subject of future clinical trials being designed by our group.

Expression of c-erb-B2 oncoprotein as a neoantigen strategy to repurpose anti-neu antibody therapy in a model of melanoma

In this study, we tested a novel approach of "repurposing" a biomarker typically associated with breast cancer for use in melanoma. HER2/neu is a well characterized biomarker in breast cancer for which effective anti-HER2/neu therapies are readily available. We constructed a lentivirus encoding c-erb-B2 (the animal homolog to HER2/neu). This was used to transfect B16 melanoma in vitro for use in an orthotopic preclinical mouse model, which resulted in expression of c-erb-B2 as a neoantigen target for anti-c-erb-B2 monoclonal antibody (7.16.4). The c-erb-B2-expressing melanoma was designated B16/neu. 7.16.4 produced statistically significant in vivo anti-tumor responses against B16/neu. This effect was mediated by NK-cell antibody-dependent cell-mediated cytotoxicity. To further model human melanoma (which expresses <5% HER2/neu), our c-erb-B2 encoding lentivirus was used to inoculate naïve (wild-type) B16 tumors in vivo, resulting in successful c-erb-B2 expression. When combined with 7.16.4, anti-tumor responses were again demonstrated where approximately 40% of mice treated with c-erb-B2 lentivirus and 7.16.4 achieved complete clinical response and long-term survival. For the first time, we demonstrated a novel strategy to repurpose c-erb-B2 as a neoantigen target for melanoma. Our findings are particularly significant in the contemporary setting where newer anti-HER2/neu antibody-drug candidates have shown increased efficacy.

How Well Does Non-mass Enhancement Correlate With DCIS/Invasive Cancer?

INTRODUCTION

Contiguous non-mass enhancement (NME) often coexists with a solid tumor component on MRI, but it can be challenging to predict whether NME represents invasive breast cancer, ductal carcinoma in situ (DCIS), benign disease, or biopsy site reaction. The purpose of this study was to determine the association between the size/extent of NME and the presence of invasive cancer and/or DCIS on final pathology.

METHODS

This was a single institution retrospective analysis of a prospectively maintained breast cancer registry (2010-2020). Female patients who underwent surgical resection were included if they had a diagnosis of invasive breast cancer (with or without DCIS) and had an MRI showing both a solid mass and contiguous NME. The size of NME on MRI was compared with the size of invasive cancer and/or DCIS on the final pathology.

RESULTS

From a total of 3443 patients, 225 patients were included. 86.2% had invasive ductal carcinoma (IDC), and 12.0% had invasive lobular carcinoma 76.9% were ER+, 16.4% were HER2+, and 13.3% were triple negative breast cancer (TNBC). 18.7% received neoadjuvant chemotherapy (NCT) of whom 31% achieved a complete radiographic/pathologic response. Pearson correlation coefficients (r) between the size of NME and invasive cancer/DCIS showed a strong and positive correlation of MRI NME with DCIS on pathology in patients without NCT. Subgroup analysis showed the strongest correlations for NME and DCIS among non-white (r = .70) and HER2 + patients (r = .74) who did not receive NCT.

CONCLUSIONS

Strong correlations between NME and DCIS were found for HER2 + disease and non-white patients, but only modest correlations were found for other patient/disease characteristics. These correlations may impact decisions in surgical approach.

A Unicorn Disease: The Large Duct Variant of Invasive Ductal Adenocarcinoma of the Pancreas

Large duct adenocarcinoma (LDA) is a rare histopathological variant of pancreatic ductal adenocarcinoma (PDAC) that closely mimics intraductal papillary mucinous neoplasm (IPMN). We present a 74-year-old female diagnosed with LDA in 2017. She was initially managed with chemotherapy and laparoscopic distal pancreatectomy. After five years of stable disease on systemic chemotherapy, she was referred to us to explore further definitive treatments. We used a multidisciplinary approach with curative-intent cytoreductive surgery and hyperthermic intraperitoneal chemotherapy (HIPEC), followed by oral maintenance chemotherapy. Subsequent scans showed stable disease; she eventually underwent neoadjuvant radiation and surgery with intraoperative radiation therapy (IORT) and achieved remission.

Abstract P3-05-25: Clinical Factors associated with Survival Outcomes in Patients with Metaplastic Breast Cancer

Background Metaplastic breast cancer (MBC) is a rare and aggressive subtype of breast cancer (BC) defined by presence of both epithelial and mesenchymal components. Most are triple negative but are often chemo-refractory and associated with poor survival outcomes compared to non-metaplastic triple negative BC. Advances in therapy have led to improvements in survival outcomes of patients (pts) with BC over the last decade. Our multicenter retrospective study aims to assess (1) progression free survival (PFS) and overall survival (OS) (2) factors predictive of survival outcomes in MBC pts Methods We performed a retrospective analysis of pts diagnosed with MBC from 1997-2021 at Mayo Clinic (Florida, Arizona and Rochester) under IRB approval. Kaplan-Meier method was used to estimate OS and PFS at 1, 3 and 5 years. Cox regression models were used to examine the association between risk factors and survival outcomes. All tests were two-sided with p value &lt; 0.05 considered statistically significant Results We evaluated 158 pts with MBC. Median age and tumor size was 61 (range: 20-91) years and 2.8 (range: 0.5-21) cm, respectively, with 80% of pts being postmenopausal. At diagnosis, 14.6% of pts had clinical T3/T4 disease, 16.4% were clinically node-positive, and 6.3% (10 pts) had distant metastases (DM). Spindle cell histology was seen in 36 pts. Most MBC pts were triple-negative (68.3%), high grade (77.2%) and high Ki-67 (36/47; 76.5%). Of the 61 pts tested for germline mutation, 8 (13.1%) were positive, with BRCA1/2, PTEN, NBN, CHEK2, and BARD1 mutations. Most pts had lumpectomy (53.8%), followed by simple mastectomy (38.5), and modified radical mastectomy (7.7%). Majority of pts had sentinel lymph node biopsy (71.8%). Adjuvant radiation therapy was performed in 65.6% of pts. Pathologic complete response (pCR) was noted in 4/38 (10.5%) evaluable pts who received neoadjuvant chemotherapy (NACT). Residual cancer burden (RCB) scores of 2 and 3 were seen in 76.2% of evaluable pts. Median follow-up time was 2.2 years (range: 6 days-24.6 years). Overall, 1-, 3-, and 5-year OS was 93.3%, 81.7%, and 76.0%, while PFS was 80.8%, 67.9%, and 60.9%, respectively. The presence of DM at diagnosis [HR 38.55 (11.18, 132.93), p &lt; 0.001] and spindle cell histology (SC) [HR 2.57 (1.19, 5.53), p = 0.02] predicted worse OS in multivariable analysis. Inferior PFS was predicted by DM [HR 18.84 (6.53, 54.35), p &lt; 0.001], SC [HR 2.46 (1.25, 4.86), p = 0.009], and node-positivity at diagnosis [HR 3.65 (1.5, 8.89), p = 0.004]. The 5-year OS and PFS were 22.2% and 0% for DM pts versus 80.0% and 65.6% for non-DM pts. The 5-year OS and PFS were 71.5% and 54.7% for SC pts versus 81% and 66.6% for non-SC pts. 5-year OS and PFS for NACT pts was 67.3% and 52.6% for NACT pts versus 78.2% and 62.8% for non-NACT pts. Age at diagnosis, menopausal status, family history of BC, grade, stage, tumor size, hormone-receptor and HER2 status, and use of NACT were not found to be significantly associated with OS or PFS in multivariate analysis. Conclusion This study is one of the largest and most recent review of institutional experiences with MBC. Overall, OS at 5 years was improved compared to prior older studies of MBC but still remains very low for those with DM, representing an area of unmet clinical need. SC and DM correlated with worse outcomes for both PFS and OS. Additionally, node positivity at diagnosis was a predictor of worse PFS. In contrast, no association was seen between survival and tumor size, stage, hormone receptor-positivity, HER2 receptor-positivity. The low pCR rates following NACT in our study are consistent with reported literature. Further, use of NACT does not impact survival, suggesting pts with resectable disease should proceed with surgery first.

Citation Format: Siven Chinniah, Raza Zarrar, Zhuo Li, Kostandinos Sideras, Alvaro Moreno-Aspitia, Saranya Chumsri, Rohit Rao, Sarah McLaughlin, James Jakub, Emmanuel Gabriel, Sanjay Bagaria, Laura Vallow, Santo Maimone, Pooja Advani. Clinical Factors associated with Survival Outcomes in Patients with Metaplastic Breast Cancer [abstract]. In: Proceedings of the 2022 San Antonio Breast Cancer Symposium; 2022 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2023;83(5 Suppl):Abstract nr P3-05-25.

Management of a Primary Retroperitoneal Yolk Sac Tumor

Patient: Male, 31-year-old

Final Diagnosis: Primary retroperitoneal yolk sac tumor

Symptoms: Lower abdominal pain

Medication:—

Clinical Procedure: —

Specialty: Oncology • Surgery

Influence of Facility Characteristics on Access to Breast Reconstruction: A 12-Year National Cancer Database Analysis

BACKGROUND/AIM

This study aimed to analyze facility characteristics contributing to disparities in breast reconstruction access in the United States.

PATIENTS AND METHODS

Data from January 1, 2004, to December 31, 2015 were extracted from the National Cancer Database on patient, facility and treatment, and tumor characteristics. A total of 858,594 patients met the inclusion criteria of the study, including 553,517 (64.5%) patients who underwent mastectomy only (without breast reconstruction) and 305,077 (35.5%) patients who received breast reconstruction (implants or autologous tissue).

RESULTS

Multivariate analysis showed that the odds of reconstruction were higher in Integrated Network Cancer Programs and Academic/Research Programs compared to Community Cancer Programs. Patients treated in the South, Midwest, and West regions had lower odds of reconstruction. Interestingly, patients treated in more than one Commission on Cancer facility had a higher likelihood of reconstruction.

CONCLUSION

Facility characteristics and location impact on access to breast reconstruction.

Topical Approach to Delivering Targeted Therapies in Lymphedema Treatment: A Systematic Review

It is estimated that 140 to 200 million people are affected by lymphedema worldwide. Many studies have proposed targeted therapies that can be delivered systemically or locally to treat lymphedema. Since lymphedema primarily affects the skin and subcutaneous tissues, topical approaches to therapy should be considered as an attractive proposition as they can avoid systemic complications. In light of this, we conducted a systematic review of publications that analyzed the use of topical approaches to delivering targeted therapies in the treatment of lymphedema. We hypothesized that topical approaches resulted in the satisfactory treatment of lymphedema. We conducted a systematic review of publications on PubMed. The main eligibility criterion was that the articles should primarily investigate the use of topical approaches to delivering targeted therapies in the treatment of lymphedema. Consequently, we excluded papers that investigated any other delivery approaches or medical conditions. Of the 174 potential studies found in the literature, six were found to fulfill our eligibility criteria. All these studies were experimental ones on small animals (mice). The authors generally proposed different types of therapies, which could be clustered into two main groups: 1) induction of lymphangiogenesis [vascular endothelial growth factor C (VEGF-C) hydrogel or fibroblast growth factor]; and 2) modulation of inflammation (tacrolimus or topical collagen gel or troxerutin-phosphatidylcholine). All studies presented positive outcomes, demonstrating that topical therapy is a promising route for delivering growth factors and anti-inflammatory agents in the treatment of lymphedema. However, studies were conducted under heterogeneous protocols, and the safe application of these therapies in humans has not been assessed. Further studies are necessary to confirm the benefits and safety of targeted topical therapy on patients with lymphedema.

Intercontinental collaborative experience with abdominal, retroperitoneal and pelvic schwannomas

Background

Schwannomas are rare tumours that pose a significant management challenge in the abdomen, retroperitoneum and pelvis. No data are available to inform management strategy.

Methods

A collaborative international cohort study, across specialist sarcoma units, was conducted to include adults presenting between 2000 and 2017 with histopathologically confirmed schwannomas within the abdomen, retroperitoneum or pelvis.

Results

Of 485 patients across 12 centres, 38 (7·8 per cent) were discharged without follow-up, 199 (41·0 per cent) underwent early resection and 248 (51·1 per cent) had radiological monitoring. Of these 248 patients, 96 (38·7 per cent) eventually had surgery, giving an overall resection rate of 60·8 per cent (295 of 485). At baseline, median tumour volume was 90·1 (i.q.r. 26·5–262·0) cm3. The estimated growth rate was 10·5 (95 per cent c.i. 9·4 to 11·6) per cent per year, and was consistent in the short term (within 2 years of diagnosis) and long term (beyond 2 years) (ρ = 0·405, P = 0·021). A decision to operate was more common in symptomatic patients (P &lt; 0·001) and for rapidly growing tumours (growth rate more than 20 per cent per year) (P = 0·025). R0/R1 resection was achieved in 91·6 per cent of patients (263 of 287). Kaplan–Meier long-term recurrence rates after R0/R1 resection were 2·3 and 6·7 per cent at 3 and 5 years respectively.

Conclusion

Specific recommendations include: indications for early surgery, prediction of growth from radiological monitoring, promotion of selective submacroscopic resection and cessation of postoperative imaging surveillance.

Eyelid Melanoma in the United States: A National Cancer Database Analysis

BACKGROUND

Eyelid melanoma (EM) is a rare condition that accounts for <1% of all cutaneous melanomas. In this analysis, patients diagnosed with EM in the United States were compared to those with other melanomas in the head and neck.

METHODS

The National Cancer Database was used to select patients with head and neck melanoma from 2004 to 2015.

RESULTS

A total of 137,233 patients met the criteria of the study. Among them, 2694 were diagnosed with EM (2%) and 134,539 in other head and neck locations (98%). Regarding the patients with EM, the mean age was 68.56 years (standard deviation 14.04). A greater number of them were treated in Academic/Research Programs (53.6%), insured by Medicare (55.7%), tumor in situ (52.2%), stage 0 (49%), and without ulceration (75.9%). The mean time to treatment commencement was 18.96 days for EM compared to 14.4 days for other melanoma in the head and neck regions (P < 0.001). There was a greater proportion of EM in female patients (odds ratio [OR] 2.371 [2.191-2.566], P < 0.001), compared to male; age greater than 80 years (OR 1.622 [1.360-1.934], P < 0.001) compared to 0 to 49 years. Moreover, EM was an independent predictor for treatment in Academic/Research Programs (OR 1.258 [1.160-1.365], P < 0.001) and diagnosis at autopsy (OR 1.414 [1.083-1.847], P = 0.011) compared to other melanoma in the head and neck region.

CONCLUSION

These novel findings have the potential to guide clinical decision making in head and neck melanoma management.

Use of Gene Transfer Vectors in Lymphedema Treatment: A Systematic Review

Different delivery mechanisms have been proposed in the literature for targeted therapies in the treatment of lymphedema. They vary from simple and direct injection to sophisticated induction of gene expression in a targeted tissue. We conducted a systematic review of publications assessing the use of viral vectors for gene transfer in lymphedema treatment. We hypothesized that viral vectors are an effective way to deliver targeted therapy in lymphedema treatment. We conducted a comprehensive systematic review of the published literature on targeted therapies associated with lymphedema surgery using the PubMed database. Eligibility criteria excluded papers that reported use of viral vectors for other medical conditions. Abstracts, presentations, reviews, meta-analyses, and non-English language articles were also excluded. From 21 potential articles found in the literature, fourteen fulfilled study eligibility criteria. Positive outcomes in terms of lymphangiogenesis were seen. The viral vectors used included adenovirus and recombinant adeno-associated virus. Most of the genes expressed were growth factors, but expression of dominant-negative transforming growth factor-β1 receptor-II or Prox1 was also proposed. Five studies targeted genetic expression on lymphedema tissue, five on transplanted lymph nodes, two on skeletal muscle, and one on adipose-derived stem cells. Publications assessing use of viral vectors for gene transfer in lymphedema treatment demonstrated that it is an effective mechanism of delivering targeted therapies. However, to date, all studies were experimental and further studies must be performed before translating these therapies into clinical practice.

Factors that Influence Chemotherapy Treatment Rate in Patients With Upper Limb Osteosarcoma

BACKGROUND/AIM

Chemotherapy is the mainstay treatment of osteosarcoma. The purpose of this study was to elucidate the factors that affect the rate of chemotherapy treatment of osteosarcoma patients.

MATERIALS AND METHODS

We queried the National Cancer Database for bone cancer patients. We included patients diagnosed with osteosarcoma of the upper extremities regardless of age and sex. With bivariate and multivariate models, we analyzed the demographic, facility, and tumor-specific characteristics, comparing the group that received chemotherapy with those that did not.

RESULTS

Female patients (OR=0.567; 95%CI=0.337-0.955), non-White patients (OR=0.485; 95%CI=0.25-0.939), and patients with government insurance (OR=0.506; 95%CI=0.285-0.9) had lower odds of receiving chemotherapy treatment than male, white, and privately insured patients. Patients with stages II (OR=4.817; 95%CI=2.594-8.946) and IV disease (OR=0.457; 95%CI=1.931-10.286) had higher odds of receiving chemotherapy than those with stage I disease.

CONCLUSION

Age, sex, race and insurance affected the rate of chemotherapy treatment in patients with upper limb osteosarcoma.

Use of Autologous Blood Components in Lymphedema Treatment: A Systematic Review

The main benefit of autologous therapies is its easier obtention and relatively lower concerns regarding ethical implications and patient safety. We conducted a systematic review of publications assessing the potential use of blood components (lymphocytes, red blood cells (RBCs), platelet-rich plasma (PRP)) as targeted therapy in the treatment of lymphedema. We hypothesized that blood components could be used as targeted therapy in the lymphedema treatment. We also conducted a comprehensive, systematic review of the published literature on the use of blood components as targeted therapies in the treatment of lymphedema using the PubMed database. Eligibility criteria excluded papers that aimed to investigate the correlation of inflammatory cells and the physio-pathogenesis of lymphedema. Abstracts, presentations, reviews, and meta-analyses were also excluded. From the 338 potential papers found in the literature, 11 studies fulfilled the eligibility criteria. Different types of targeted therapies were proposed, but the majority of papers investigated the potential use of lymphocytes (9/11). The use of PRP was investigated in two papers and the use of RBCs in one paper. Interestingly, six out of 11 studies were done on patients with lymphedema, but the most recent was published in 1999. The remaining publications were experimental studies on dogs, rats, or in vitro. The publications demonstrated positive outcomes for the delivery of lymphocytes and PRP in lymphedema treatment. Lymphocyte was the most common blood component investigated. Even though more than half of the papers found were conducted on patients, we noticed a scientific gap of more than 20 years on the topic.

Comparing morbidity rates between wise pattern and standard horizontal elliptical mastectomy incisions in patients undergoing immediate breast reconstruction

BACKGROUND

Breast cancer patients with ptotic breasts pursuing mastectomy with immediate reconstruction can present challenges. A wise pattern (inverted-T) mastectomy incision (WPM) has been suggested as an alternative to the standard horizontal elliptical mastectomy (EM) to reduce redundant skin and correct ptosis. Herein, we sought to examine the differences in morbidity between the two techniques.

METHODS

We performed a retrospective review of women undergoing mastectomy with immediate reconstruction at our institution from June 2007 to January 2016. We compared those undergoing WPM to a control population undergoing EM. Statistical analysis was performed evaluating clinical, pathological, and surgical outcome variables according to patient and per breast. All tests were two-sided with alpha level set at 0.05 for statistical significance.

RESULTS

A total of 241 women underwent mastectomy and reconstruction in 421 breasts; 78/241 (32%) had WPM (149 breasts), 163/241 (68%) had EM (272 breasts). Both groups were similar in age, smoking status, diabetes, race, tumor type, and pathologic stage (all P > 0.07). Skin flap necrosis was the most frequently encountered complication, occurring in 58/149 (38.9%) of WPM breasts and in 24/272 (8.9%) of EM breasts (P < 0.0001). There was no difference in the need for revisional procedures between the groups (WPM: 24.1% vs EM: 17.6%, P = 0.207).

CONCLUSION

Patients should be counseled WPM is associated with higher rates of skin flap necrosis. However, this does not translate into higher rates of revisional procedures or return to OR.

FOXC1 identifies basal-like breast cancer in a hereditary breast cancer cohort

Breast cancers arising in the setting of the hereditary breast cancer genes BRCA1 and BRCA2 are most commonly classified as basal-like breast cancer (BLBC) or luminal breast cancer, respectively. BLBC is an aggressive subtype of breast cancer associated with liver and lung metastases and poorer prognosis than other subtypes and for which chemotherapy is the only systemic therapy. Multiple immunohistochemical markers are used to identify the basal-like subtype, including the absence of estrogen receptor alpha, progesterone receptor, and human epidermal growth factor receptor 2. Forkhead box C1 (FOXC1) has been identified as a specific marker expressed in BLBC in general breast cancer cohorts. We examined an institutional cohort of breast cancer patients with germline BRCA1 (n=46) and BRCA2 (n=35) mutations and found that FOXC1 expression on immunohistochemical staining is associated with BRCA1 vs BRCA2 mutations [30/46 vs. 6/35]. In BRCA1 mutant tumors, FOXC1 was expressed in 28/31 BLBC tumors and 2/13 non-BLBC tumors, In BRCA2 mutant tumors, FOXC1 was expressed in 5/5 BLBC tumors and 1/30 non-BLBC tumors. In cell culture models of BRCA1-mutant breast cancer, FOXC1 is associated with increased proliferation and may serve as a marker for sensitivity to PARP-inhibitor therapy with olaparib.

Lichenoid dermatitis in three patients with metastatic melanoma treated with anti-PD-1 therapy

Therapies that activate the immune system through blocking the binding of programmed death ligand 1 (PD-L1) present on tumors and PD-1 (programmed death 1) present on activated immune cells are revolutionizing the care for patients with cancer. These therapies work by inhibiting negative regulators of the immune system, thereby decreasing a tumor's ability to evade the immune system. The side effects of anti-PD-1/PD-L1 therapies are generally mild and as expected are related to autoimmune reactions. Two of the most common side effects of anti-PD-1/PD-L1 therapies are rash and pruritus occurring in approximately 20% of patients. Although the rash is generally recognized to be immune mediated, the exact mechanisms of the rash remain unclear. Herein, we report three cases of lichenoid dermatitis in three patients treated with MK-3475 (anti-PD-1) that were characterized with marked T-cell infiltrates with few PD-1-positive cells. The rashes in all three patients were relatively mild, allowing treatment to continue despite the rashes.

Breast cancer recurrence in patients receiving epidural and paravertebral anesthesia: a retrospective, case-control study

PURPOSE

Studies have suggested an association between the use of regional paravertebral or epidural anesthesia and a reduction in tumor recurrence following breast cancer surgery. To examine this relationship we performed a retrospective case-control study of patients undergoing breast cancer surgery receiving regional, regional and general, or general anesthesia.

METHODS

A retrospective chart review was performed of patients undergoing surgery for stage 0 to III breast cancer. Patients identified as receiving regional anesthesia were then matched for age, stage, estrogen receptor (ER) status, progesterone receptor status, and HER-2 expression with patients who received no regional anesthesia. Univariate (Pearson's χ2 test and odds ratio) and multivariate logistic analyses with backward stepwise regression were performed to determine factors associated with cancer recurrence.

RESULTS

Between 1998 and 2007, 816 women underwent surgery for stage 0-III breast cancer at our institution. Forty-five patients developed tumors. Univariate analysis showed the use of regional anesthesia trended towards reduced cancer recurrence, but it did not achieve statistical significance (p = 0.06). Higher recurrence rates were associated with ER positive status (p = 0.003) and higher tumor stage (p < 0.0001). Age and HER-2 status were not associated with increased cancer recurrence (both p > 0.11). Multivariate analysis confirmed ER status and stage as independently influential (p = 0.002 and p < 0.0001 respectively).

CONCLUSION

Although we found a trend towards reduced breast cancer recurrence with the use of regional anesthesia, univariate analysis did not reach statistical significance.

Trends in risk reduction practices for the prevention of lymphedema in the first 12 months after breast cancer surgery

BACKGROUND

Lymphedema is a feared complication of breast cancer surgery. We evaluated the trends in lymphedema development, patient worry, and risk reduction behaviors.

STUDY DESIGN

We prospectively enrolled 120 women undergoing sentinel node biopsy (SLNB) or axillary node dissection (ALND) for breast cancer and assessed lymphedema by upper extremity volume preoperatively and at 6 and 12 months postoperatively. We defined lymphedema as a >10% volume change from baseline relative to the contralateral upper extremity. Patients completed a validated instrument evaluating lymphedema worry and risk reducing behaviors. Associations were determined by Fisher's exact and signed rank tests.

RESULTS

At 6 months, lymphedema was similar between ALND and SLNB patients (p = 0.22), but was higher in ALND women at 12 months (19% vs 3%, p = 0.005). A clear relationship exists between relative change in upper extremity volume at 6 and 12 months (Kendall tau coefficient 0.504, p < 0.001). Among the women with 0 to 9% volume change at 6 months, 22% had progressive swelling, and 18% resolved their volume changes at 12 months. Overall, 75% of ALND and 50% of SLNB patients had persistent worry about lymphedema at follow-up, and no difference existed in the number of risk reducing behaviors practiced among the 2 groups (p > 0.34).

CONCLUSIONS

Upper extremity volumes fluctuate, and there is a period of latency before development of lymphedema. Despite the low risk of lymphedema after SLNB, most women worry about lymphedema and practice risk reducing behaviors. Additional study into early upper extremity volume changes is warranted to allay the fears of most women and better predict which women will progress to lymphedema.

Abstract 3742: FOXC1 is a potential prognostic marker with functional significance in basal-like breast cancer

Although basal-like breast cancer (BLBC) is a distinct molecular subtype, it has no defining gene or protein marker that can be used as the basis for therapy. Estrogen receptor (ER) and HER2 receptor guide treatment of luminal and HER2 breast cancer subtypes, respectively, but chemotherapy is still the only systemic treatment available for BLBC. In view of its poor clinical outcomes, high proliferation rates and preferential metastasis to the brain, there is an urgent need for effective targeted therapy of BLBC.

In a previous study using cDNA microarray analyses and immunohistochemistry of archival breast cancer tissue specimens, we showed consistent and exclusive overexpression of FOXC1 in BLBC versus other molecular subtypes. FOXC1 overexpression was significantly associated with poor overall survival and brain metastasis. In the present study, we show that overexpression of FOXC1 in breast cancer cells with low endogenous FOXC1 levels increased cellular proliferation, migration, and invasion, and induced epithelial-mesenchymal transition. Knockdown of FOXC1 by shRNA in breast cancer cells with high endogenous FOXC1 expression had the opposite effect. Cell signaling studies showed that FOXC1 activated the NF-κB pathway by upregulating the peptidyl-prolyl isomerase Pin1 and downregulating the ubiquitin ligase SOCS-1. Pin1 binds to p65, inhibits the p65 interaction with IκBα, and thus enhances p65 nuclear localization and protein stability. SOCS-1 directly interacts with p65 and promotes its degradation. FOXC1 knockdown reduced p65 protein levels and NF-κB activity. The importance of the NF-κB pathway for FOXC1 function was confirmed by the increased sensitivity to NF-κB inhibitors in cells that overexpressed FOXC1. Because BLBC under-expresses ER, FOXC1 was inversely associated with ER, as expected. Interestingly, FOXC1 repressed ER transcription and activity via NF-κB signaling, and FOXC1 overexpression switched MCF-7 breast cancer cell growth from estrogen-dependent to estrogen-independent. This may explain why ER is not normally detected in BLBC.

These results suggest that FOXC1 may be a specific diagnostic and prognostic biomarker for BLBC and may play an important role in regulating aggressive traits associated with BLBC. It might also serve as a potential molecular therapeutic target for BLBC.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 3742.