Kasumi Morimitsu

Prediction of macrometastasis in axillary lymph nodes of patients with invasive breast cancer and the utility of the SUV lymph node/tumor ratio using FDG-PET/CT

BackgroundAxillary lymph node dissection (ALND) is important for improving the prognosis of patients with node-positive breast cancer. However, ALND can be avoided in select micrometastatic cases, preventing complications such as lymphedema or paresthesia of the upper limb. To appropriately omit ALND from treatment, evaluation of the axillary tumor burden is critical. The present study evaluated a method for preoperative quantification of axillary lymph node metastasis using positron emission tomography/computed tomography (PET/CT).MethodsThe records of breast cancer patients who received radical surgery at the Gifu University Hospital (Gifu, Japan) between 2009 and 2014 were reviewed. The axillary lymph nodes were preoperatively evaluated by PET/CT. Lymph nodes were dissected by sentinel lymph node biopsy (SLNB) or ALND and were histologically diagnosed by experienced pathologists. The maximum standardized uptake value (SUVmax) was measured in both the axillary lymph node (SUV-LN) and primary tumor (SUV-T). The SUV-LN/T ratio (NT ratio) was calculated by dividing the SUV-LN by the SUV-T, and the efficacies of the NT ratio and SUV-LN were compared using receiver operating characteristic (ROC) curve analysis. The diagnostic performance was also compared between the techniques with the McNemar test.ResultsA total of 171 operable invasive breast cancer patients were enrolled, comprising 69 node-positive patients (macrometastasis (Mac): n = 55; micrometastasis (Mic): n = 14) and 102 node-negative patients (Neg). The NT ratio for node-positive patients was significantly higher than in node-negative patients (0.5 vs. 0.316, respectively, P = 0.041). The NT ratio for Mac patients (0.571) was significantly higher than in Mic (0.227) and Neg (0.316) patients (P <0.01 and P = 0.021, respectively). The areas under the curves (AUCs) by ROC analysis for the NT ratio and SUV-LN were 0.647 and 0.811, respectively (P <0.01). In patients with an SUV-T ≥2.5, the modified AUCs for the NT ratio and SUV-LV were 0.757 and 0.797 (not significant).ConclusionThe NT ratio and SUV-LN are significantly higher in patients with axillary macrometastasis than in those with micrometastasis or no metastasis. The NT ratio and SUV-LN can help quantify axillary lymph node metastasis and may assist in macrometastasis identification, particularly in patients with an SUV-T ≥2.5.

Clinical significance of glycoprotein nonmetastatic B and its association with HER2 in breast cancer

Glycoprotein nonmetastatic B (GPNMB) is a potential oncogene that is particularly expressed in melanoma and breast cancer (BC). To clarify its clinical significance in BC, we measured serum GPNMB in vivo and investigated its cross talk with human epidermal growth factor 2 (HER2). GPNMB was expressed in four of six breast cell lines (SK‐BR‐3, BT‐474, MDA‐MD‐231, and MDA‐MD‐157), two of six colorectal cell lines, and two of four gastric cancer (GC) cell lines. We established a GPNMB quantification system using enzyme‐linked immunosorbent assay (ELISA) for these cell lines. We measured serum GPNMB in vivo in 162 consecutive BC patients and in 88 controls (50 colorectal cancer [CC] and 38 GC patients). The GPNMB concentration in BC, CC and GC was 8.163, 5.751 and 6.55 ng/mL, respectively. The GPNMB level was significantly higher in BC patients than in CC patients (P = 0.021). The HER2‐rich subtype of BC patients had significantly higher GPNMB levels than other subtypes (vs. Luminal; P = 0.038; vs. DCIS; P = 0.0195). These high GPNMB levels decreased after treatment (surgery/chemotherapy). Next, we examined the relationship between GPNMB and HER2 in vitro using SK‐BR3 and BT‐474 (HER2‐positive/GPNMB‐positive) cells. GPNMB depletion by small interfering RNA (siRNA) increased both HER2 expression and phosphorylation. Trastuzumab (Tra) in combination with docetaxel promoted cell growth inhibition, and treatment with Tra or an Extracellular signal‐related kinase (ERK) inhibitor enhanced GPNMB expression. These results indicate that GPNMB might be a surrogate marker for BC and may cross talk with the HER2 signal pathway. GPNMB may therefore emerge as an important player in anti‐HER2 therapy.

Cytokeratin-positive fibroblastic reticular cell tumor with follicular dendritic cell features: a case report and review of the literature.

Fibroblastic reticular cell (FRC) neoplasms, which are one of the histiocyte tumor types, are very rare. Here we report a cytokeratin (CK)-positive FRC neoplasm having features of follicular dendritic cells in a 54-year-old woman with right axillary lymph node swelling. The resected lymph node showed multiple nodular aggregations simulating and replacing normal follicles. The tumor cells had a uniform, large and oval to polygonal shape, abundant cytoplasm, and various sizes of nuclei with central eosinophilic nucleoli and coarse nuclear chromatin. They were positive for CK AE1/AE3+CAM5.2, CK7, tenascin C, l-caldesomone, and CD21, weakly positive for S100, and negative for CD1a. Ultrastructurally, the tumor cells had long interdigitating microvillus-like cell processes and oval to elongated vesicular nuclei. In addition, the intercellular spaces contained accumulations of collagen, and some tumor cells had desmosomal-like junctions. These findings suggest that the present case is a CK-positive FRC tumor with follicular dendritic cell features.

Changes in Protein Level in the Cerebrospinal Fluid of a Patient with Cerebral Radiation Necrosis Treated with Bevacizumab

A 32-year-old woman underwent surgeries and radiation therapy for astrocytoma. She developed symptomatic radiation necrosis in the lesion, which caused hydrocephalus. She initially underwent ventricular drainage, because the protein level in the cerebrospinal fluid (CSF) was 787 mg/dL, which was too high for shunt surgery. Because she also had breast cancer, which was pathologically diagnosed as an invasive ductal carcinoma, standard bevacizumab therapy in combination with paclitaxel every 2 weeks was selected. Interestingly, after 2 days, the agents had dramatically reduced the CSF protein level. However, it returned to approximately the initial level within 2 weeks. After two courses of this regimen, a ventriculoperitoneal shunt was placed. After 10 courses of this regimen, the CSF protein level decreased to 338 mg/dL, which is less than half of the initial level. Long-term administration of bevacizumab might decrease leakage of protein from the vessels around the ventriculus.

Effective Hormone Therapy Reduces the Efficacy of Subsequent Chemotherapyin Hormone-Receptor-Positive Metastatic Breast Cancer

Objective: Hormone Therapy (HT) is usually introduced to patients with hormone-receptor-positive metastatic breast cancer without life-threatening metastasis prior to chemotherapy. Many physicians expect HT not to affect the efficacy of subsequent chemotherapy, but there is no evidence to confirm this. In this retrospective study, we investigated the efficacy of chemotherapy after hormone therapy for metastatic breast cancer. Methods: Patients who received chemotherapy after hormone therapy for metastatic breast cancer between 2004 and 2014 at our institution were reviewed, and the efficacy of HT and the efficacy of subsequent chemotherapy were evaluated based on the tumor response and the duration of the therapy. If multiple-line therapies were introduced, the efficacies were evaluated by the best response, longest duration among therapies, and total duration of therapies, and we analyzed the relationship between the efficacies of HTs and chemotherapies. Results: Twenty-nine patients were eligible. The median patient age was 60 years old. The major metastatic sites included bone (17 patients), the lungs (10 patients), and lymph nodes (10 patients). The clinical benefit (CB) rate of all HTs was 62% and the patients received HTs for a median of 20.4 months. Meanwhile, the CB rate of all chemotherapies was 79%, and the patients received chemotherapies for a median of 24.8 months. The CB rates, the longest durations, and the total durations of prior HTs were not associated with the efficacy of subsequent chemotherapy. However, the total duration of the chemotherapies in the patients with very effective HTs (total duration of HTs>20 months, longest duration of HT>14 months, and HTs with CBs) was significantly shorter than for the others (MST 13.1 m vs. 26.8 m; p=0.035). Conclusions: These results suggest that the efficacy of chemotherapies was reduced after very effective HTs.

Abstract 4319: Clinical significance and possible role of GPNMB in patients with breast cancer

Glycoprotein non-metastatic B (GPNMB) is a type I transmembrane protein, which is isolated from differential expression assay using metastatic melanoma cells. The physiological function is very little known but may be supposed to be associated with cell invasion and motility particularly in breast cancer cells. Here we investigated the role of GPNMB in breast cancer. First we checked expression of GPNMB by RT-PCR and western blot in several cancer cell lines including breast, gastric, and colon cancer followed by establishment of GPNMB measurement by ELISA because it9s reported that GPNMB is shed at extracellular domain by sheddase such as ADAM10. GPMNB expressed in breast (5/6:83%), gastric (3/6:50%), colon (1/7:14.3%) cancer cell lines. Of breast cancer cell lines, GPNMB was highly expressed in SK-BR3 (HER2 positive), BT474 (HER2/ER positive), MDA-MB-157 (Triple negative) cells. Shed GPNMB in culture medium was measurable and correlated with expression of each cell line. Next we evaluated serum GPNMB in patients with breast (n = 164; primary 119, metastatic 43), gastric (n = 38), and colorectal (n = 50) cancer in our institute from 2011.9-2014.2.) This study was approved by the central ethics committee of Gifu University. Serum GPNMBs were 9.403, 5.751, 6.550 ng/ml, respectively. GPNMB for breast cancer patients was statistically higher than those by colorectal cancer patients (p = 0.018). Of breast cancer patients, GPNMB for HER2-type patients was higher than those for Luminal type and DCIS patients (p = 0.0386, p = 0.0195, respectively). Those for triple negative patients was also higher than those for DCIS patients (p = 0.0459). Interestingly, serum GPNMB was dramatically reduced in accordance with chemotherapy in some patients. Based on these clinical observations, we further investigated relationship between GPNMP and HER2 in vitro. Blockage of GPNMB induced not only HER2 but also EGFR expression. On the other hand, inhibition of HER2 by trastuzumab increased expression of GPNMB. Depletion of GPNMB increased sensitivity of trastuzumab, suggesting that GPNMB may play an important role in crosstalk of signal transduction for breast cancer. These notions may suggest a novel therapeutic strategy to overcome HER2 positive breast cancer. Citation Format: Manabu Futamura, Masako Kanematsu, Atsuko Yamada, Kasumi Morimitsu, Akemi Morikawa, Ryutaro Mori, Kazuhiro Yoshida. Clinical significance and possible role of GPNMB in patients with breast cancer. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 4319. doi:10.1158/1538-7445.AM2015-4319