Benign metastasizing leiomyomas (BML) represent a rare phenomenon consisting of the extra-uterine spread of smooth muscle cells with similar histological, immunological, and molecular patterns to those of benign uterine leiomyomas. They are considered benign based off their low mitotic activity, lack of anaplasia or necrosis, and limited vascularization. This condition represents an interesting diagnostic and treatment challenge based on their rarity and indolent nature. Our case represents a unique finding of BML in the thoracic spine in a postmenopausal woman many years after hysterectomy and partial oophorectomy. There are currently no standard guidelines for treatment of BML, given the rare nature of this condition, with most patients treated with a combination of surgical resection and radiotherapy, followed by hormonal treatment and radiological surveillance serving as the primary backbone of current management plans. Given that these patients present a unique clinical challenge in terms of diagnosis and management, it is important to delineate and further examine these rare entities.

Accessory male breast cancer (BC) is a rare entity and is associated with poor outcome. We report a 76-year-old patient who was diagnosed with concurrent accessory breast and primary lung cancer, both were positive for somatic BRCA-2 (E1593D) mutation. He received concurrent radiation and platinum-based chemotherapy for lung cancer with good response, but breast cancer progressed in about 8 months, and further progressed after single agent anastrozole in 10 months. Next Generation Sequencing (NGS) of breast cancer was also positive for CCND1 (Cyclin D1) and FGFR1 amplifications. Despite a poor molecular profile of breast cancer, and progression following platinum-based chemotherapy and anastrozole, he was successfully treated with the Cyclin-dependent kinase (CKD) 4/6 inhibitor palbociclib, estrogen-receptor down-regulator fulvestrant and luteinizing hormone-releasing hormone (LHRH) agonist leuprolide with the duration of response of 21 months which has exceeded duration of response to prior treatments. This case is of interest given FDA expanded the approval of palbociclib in combination with AI or fulvestrant for male patients with HR–positive, HER2-negative metastatic breast cancer in Apr. 2019 based on real-world data from electronic health records.

Sinonasal undifferentiated carcinoma (SNUC) is a rare, poorly differentiated and aggressive malignancy of the nasal cavity and paranasal sinuses first reported by Frierson et al. in 1986 with less than 300 known cases reported since then. Due to the rarity and aggressive nature of the disease, there is a lack of consensus regarding optimal management in these patients. Treatment decisions have mostly been guided by a small number of cases series and can vary widely between institutions. In this unique case presentation, we review a case of sinonasal undifferentiated carcinoma in a young Hispanic male reviewing the literature on a rare disease, in order to elucidate effective treatment options for improved future outcomes. Based off of literature review and prior case series, the multiple modality approach should result in the best possible outcome for this rare and aggressive disease. In this specific case of a young Hispanic male with Stage IVB SNUC, we proceeded with Neo-adjuvant TPF (Docetaxel, cisplatin and fluorouracil) with effective results, followed by Cisplatin and concurrent radiation once the patient had interval progression, and was deemed unresectable. Given the rarity and complexity of this disease, a prospective randomized controlled study should eventually be pursued to properly determine the most effective mode and combination of therapies. At this time treatment can only be based on reported case series and a small number of retrospective studies, and therefore it is important to continue to evaluate different institutions’ methods of treatment.

Background:Circulating Tumor Cells(CTCs) have prognostic implications in patients with metastatic breast cancer(MBC).During the Epithelial Mesenchymal Transition(EMT), CTCs acquire a more mesenchymal phenotype. Hence, methodologies such as the Cell search that rely on the expression of an epithelial marker EpCAM in CTCs fail to capture a subset of CTCs undergoing the process of EMT and therefore do not adequately represent the true circulatory metastatic load. Hitachi chemicals has invented a size based micro cavity array (MCA) system that allows for the isolation of tumor cells based on the differences in size and deformability between tumor and blood cells. Photolithography and the metal plating can precisely control the filter pore size of our system. Our platform is more sensitive than the Cell Search method in detecting CTCs in Lung Cancer. Cancer Associated Fibroblasts (CAFs) are a major component of the breast tumor microenvironment. Using a micro filter capture technique, our co-authors have demonstrated that CAFs can be enumerated as circulating CAFs (cCAFs). Hitachi's Micro cavity Array System has not been evaluated in the detection of CTCs and cCAFs in patients with Breast Cancer. The purpose of this study is to demonstrate that CTCs and cCAFs can be enumerated using our platform and the cCAFs can serve as biomarkers of metastasis simultaneously with CTCs. Method:We undertook a Pilot study of 20 patients each with breast cancer across Stage I, Stage II, Stage III and Stage IV. A total of 10ml of peripheral blood was obtained from each patient. Enumeration of CTCs and cCAFs was carried out by the size based mircocavity array system invented by Hitachi Chemicals. Identification of these cells was done by a triple Immunofluorescence staining for pan-CK (cytokeratin), FAP (Fibroblast Activated Protein) and CD45. CTCs were identified as CK+, CD45-, FAP- cells and cCAFs were identified as FAP+, CK- and CD 45 negative cells. Result:Our method had a high cell recovery rate (90%or higher) and efficient white blood cells depletion rate (99.99%). We present the data from a total of 13 patients in this abstract, (two with stage III and eleven with stage IV breast cancer) . Data from rest of the subjects will be presented at the actual meeting. We detected the presence of CTCs in 11/11(100%) in patients with stage IV(mean of 44) and in 2 out of 2 (100%) patients with Stage III Breast Cancer. We detected the presence of cCAFs in 1 out of 2 patients( 50%) with stage III and in 8 of 11(81.8%) (mean of 9)patients with stage IV breast cancer( Fisher's exact test p-value= 0.42). The number of CTCs and cCAFs was significantly elevated in patients with MBC and the number was clinically associated with a high metastatic burden. Conclusions:CTCs and cCAFs can be enumerated using a size based size based micro cavity array invented by Hitachi Chemicals that does not rely on the expression of epithelial markers in CTCs. CTCs and cCAFs can be detected in patients with stage III and stage IV breast cancer. CTCs and cCAFs were associated with high metastatic burden and their numbers were significantly elevated in patients with MBC. cCAFs could serve as biomarkers alongside of CTCs in MBC. Citation Format: Parajuli R, Ly R, Ziogas A, Eapen A, Lane K, Chen J, Lin E, Mehta R, Tsai A. Micro-cavity array system for size-based enrichment of circulating tumor cells and circulating cancer associated fibroblasts from blood of patients with breast cancer [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr P3-01-16.