H.M. Lee

Clinical usefulness of fluorescence in situ hybridization for diagnosis and surveillance of bladder cancer

We evaluated the performance of the fluorescence in situ hybridization (FISH) assay in comparison with that of urinary cytology for the detection of bladder urothelial carcinoma in routine clinical practice. Voided urine samples from 602 patients with hematuria were analyzed. The bladder cancer group consisted of 95 patients who had biopsy-proven bladder cancer, and the control group consisted of 507 patients without bladder cancer. We found a significant difference between the overall sensitivities of FISH and cytology (60% vs. 28.4%, respectively; P < 0.0001). The overall specificity was 99% with cytology and 94.9% with FISH, although this difference was not statistically significant. The mean values for all four probes in the true-positive group were higher than those in the false-positive group. The difference in the mean values between the two groups was significant only for the CEP3 and CEP17 probes. Furthermore, the severity of the genetic alterations detected by FISH showed a positive correlation with both tumor invasiveness (stage Ta --> T1, T2) and histological grade (G1, G2 --> G3). Together, these findings suggest that FISH can be a useful diagnostic and surveillance tool for patients who are suspected of having new or recurrent bladder cancer.

Detection rate of clinically insignificant prostate cancer increases with repeat prostate biopsies

To analyze if clinically insignificant prostate cancer (CIPC) is more frequently detected with repeat prostate biopsies, we retrospectively analyzed the records of 2146 men diagnosed with prostate cancer after one or more prostate biopsies. The patients were divided into five groups according to the number of prostate biopsies obtained, e.g. group 1 had one biopsy, group 2 had two biopsies and group 3 had three biopsies. Of the 2146 patients diagnosed with prostate cancer, 1956 (91.1%), 142 (6.6%), 38 (1.8%), 9 (0.4%) and 1 (0.1%) men were in groups 1, 2, 3, 4 and 5, respectively. Groups 4 and 5 were excluded because of the small sample sizes. The remaining three groups (groups 1, 2 and 3) were statistically analyzed. There were no differences in age or prostate-specific antigen level among the three groups. CIPC was detected in 201 (10.3%), 28 (19.7%) and 9 (23.7%) patients in groups 1, 2 and 3, respectively (P<0.001). A multivariate analysis showed that the number of biopsies was an independent predictor to detect CIPC (OR=2.688 for group 2; OR=4.723 for group 3). In conclusion, patients undergoing multiple prostate biopsies are more likely to be diagnosed with CIPC than those who only undergo one biopsy. However, the risk still exists that the patient could have clinically significant prostate cancer. Therefore, when counseling patients with regard to serial repeat biopsies, the possibility of prostate cancer overdiagnosis and overtreatment must be balanced with the continued risk of clinically significant disease.

Cytopathological Study of the Circulating Tumor Cells filtered from the Cancer Patients’ Blood using Hydrogel-based Cell Block Formation

Circulating tumor cells have emerged as biomarkers for estimating the tumor burden and metastatic potential of cancer patients. However, to date, most of studies and applications of circulating tumor cells have been conducted and applied to epithelial cancers such as breast, colorectal, and prostate tumor. The only FDA-cleared method, CellSearch, makes use of antibody against epithelial surface protein expressed on CTCs, thus obstructing wide application for various cancers with non-epithelial and semi-epithelial characteristics including renal cell carcinoma. Due to rarity and ambiguity of CTCs, designed experiment including non-biased CTC isolation and subsequent cytopathological study for finding applicable immunomarkers are urgently needed for clinical use of CTCs for less-studied cancers. Here, in order to construct the fundamental step for CTC diagnosis without limitation of its epithelial characteristics, we present the simple and novel method which incorporate both label-free CTC isolation and pathological study using hydrogel-based cell block formation. Six cell lines from lung, ovarian, kidney cancers were used to make cell block and analyzed by conventional immunocytochemical staining method to find the candidate markers for CTC. Especially for renal cancer, the physically isolated CTCs were further immunocytochemically examined with the screened candidate markers by cell block construction, and verified their clinical utility using blood samples from patients with renal cell carcinoma. This comprehensive study demonstrates that the present approach can be used to find the potential markers for any type of cancers regardless of their epithelial characteristics and isolate the specific type of CTCs in label-free manners.

Pelvic lymph node metastases in prostate cancer: Preoperative detection with dynamic contrast-enhanced magnetic resonance imaging compared with postoperative pathologic result of pelvic lymph node dissection

Received October 20, 2017, Revised October 23, 2017, Accepted October 23, 2017 Corresponding Author: Byeongdo Song Department of Urology, Seoul National University Bundang Hospital, 82 Gumi-ro 173beon-gil, Bundang-gu, Seongnam 13620, Korea E-mail: uromedi@naver.com Tel: +82-31-787-7345, Fax: +82-31-787-4057 ORCID code: https://orcid.org/0000-0003-3961-1258 ᆞThis research was supported by a grant of the Korean Health Technology R&D Project through the Korea Health Industry Development Institute (KHIDI), funded by the Ministry of Health & Welfare, Republic of Korea (grant number: HI17C1264).

Abstract 3775: Hydrogel-assisted pathological study of the circulating tumor cells filtered from the renal cell carcinoma patients’ blood

Introduction: Circulating tumor cells (CTCs), defined as tumor cells detached from the primary tumor site and circulating in the peripheral blood, are a promising marker to get the information about tumor status and metastatic potential. However, the limited detection ability as well as their biased specificity of current CTC isolation struggle from understanding the comprehensive characteristics of CTCs. In addition, previous CTC isolation depending on epithelial cell adhesion molecule (EpCAM) antibody make their cytological and pathological study hard. We developed the methods which capture CTCs based on their size and deformability, and construct a hydrogel-assisted cell block for verifying the diagnostic utility for various cancer-associated immuno-markers and their pathological studies. Methods: Two renal cell carcinoma cell lines, SN12C and 769P, and 7 different cancer patients’ blood with renal cell carcinoma were used. To find the applicable markers for diagnosing renal cell carcinoma, we constructed the cell blocks of two cell lines. For the encapsulation of the cells, 4 % alginate was prepared by dissolving in deionized water under constant stirring at 85 °C. Then, the separately prepared renal cancer cells were gently mixed into the dissolved alginate solution. After careful mixing, the solution was loaded into calcium chloride solution drop by drop using volume pipette, followed by 15 min of further incubation with constant stirring. Next, the cell-containing beads were applied to the commonly used procedure for paraffin tissue blocks, and 8 different cancer-associated immuno-markers (EpCAM, CK (AE1/AE3), CAM5.2, EMA, CD10, CA IX, RCC, and vimentin) were stained with each dissected cell blocks. The CTCs from the 7 clinical samples were isolated by tapered-slit filter, and cell containing slides were immunohistochemically stained and examined by pathologist. Results: The four markers, EpCAM, CK (AE1/AE3), CD10, and vimentin in the SN12C cell block were highly expressed. The three markers, CK (AE1/AE3), CD10, and vimentin in the 769-P cell block were predominantly expressed. The EpCAM, CK (AE1/AE3), and CD10 are chosen as the potential immunomarkers for CTC-based diagnosing for RCC. In the clinical study using the 0.5-3.0 ml of blood samples, CTCs were successfully isolated and detected immunohistochemically in 57.1 % (4 of 7) of patients and ranged from 1 to 5. Of 4 CTC positive samples, two had CK (AE1/AE3) positive, each one had EpCAM and CD10 positive CTCs, respectively. Discussion and conclusion: Although the vimentin is highly expressed in both cell blocks, due to diffuse positivity for leukocyte, single use of vimentin for cancer diagnosis is limited. This comprehensive study including immuno-markers screening and their applicability test with clinical samples demonstrates the clinical utility of the present device and hydrogel-assisted cell block for CTC isolation and cancer studies. Citation Format: Yoon-Tae Kang, Young Jun Kim, Tae Hee Lee, Hee Jin Chang, Hyun-Moo Lee, Young-Ho Cho. Hydrogel-assisted pathological study of the circulating tumor cells filtered from the renal cell carcinoma patients’ blood [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 3775. doi:10.1158/1538-7445.AM2017-3775

Abstract P5-09-17: Prognostic significance of progesterone receptor in hormonal receptor-positive breast cancer: Association with endocrine resistance

Background: Endocrine therapy has dramatic improvements of prognosis in patients with hormonal receptor positive breast cancer. However, long-term follow up shows that endocrine resistance is still major clinical concern. Although the value of estrogen receptor (ER) level can predict response to endocrine treatment in hormonal receptor positive breast cancers, few markers are available that can predict response to endocrine treatment. We attempted to identify molecular markers, especially progesterone receptor (PR), associated with endocrine failure in breast cancer. Methods: We reviewed the medical records of 2513 breast cancer patients who underwent breast surgery and endocrine therapy at Samsung Medical Center between March 2007 and July 2011. Patients were compared according to ER and PR expression and to assess the clinical and biological features of ER+positive/PR-negative breast cancers to understand how PR might be a useful marker of these activities. ER and PR expression accessed using Allred score, the ‘positive” was defined that total score is larger than 2. Results PR negative tumors were found more frequently in postmenopausal women (post- 11.2% vs. pre- 2.5%, P Conclusion: In HR positive breast cancers, PR negative tumors were found more frequently in elderly, postmenopausal women. However, PR negative tumors are shown more aggressive and poorer survival than PR positive tumors despite of endocrine therapy, especially in premenopausal women. Citation Information: Cancer Res 2013;73(24 Suppl): Abstract nr P5-09-17.