- Email: [email protected]
710 Optomagnetic imaging spectroscopy in characterisation of cervical tissue and cancer detection using unstained sample approach
S130 be useful as diagnostic and prognostic markers and may be the excellent targets for chemotherapy. Quantum dots (QDs) are semiconductor nanocrystals (e.g., group II−IV) with a size range of 2 to 10 nm in diameter. Compared with traditional organic fluorescent dyes, QDs exhibit advantages of high quantum yield, much enhanced photostability and narrow emission band, making them ideal for biomedical imaging. Materials and Methods: Mercaptosuccinic acid (MSA) capped cadmium telluride/cadmium sulfide (CdTe/CdS) QDs were recently developed in our laboratory. Hepatocellular carcinoma was induced by intrahepatic implantation of 107 Hepa1−6 cells into BALB/c nude mice via open surgical technique and imaging procedures were performed after 14 days. QDs were imaged in tumorous, peri-tumoral and normal liver tissue of the same mouse after intravenous injection by multiphoton microscopy (MPM) coupled with fluorescence lifetime imaging (FLIM), with cellular resolution (~1 mm). Results: These QDs have an average particle diameter of 2.1 nm, and display abroad excitation (<500 nm) with an emission peak of 530 nm. The zeta potential measured was −-52 mV. QDs were found to evenly distribute in vascular of all tissues but not be taken up by cells 30 min after intravenous injection, which made vasculature of these tissues highly visible. Compared to highly regulated and controlled sinusoids in normal liver tissue, peri-tumoral sinusoids became irregular and attenuated, while disordered, tortuous and immature neovessels were observed in tumors. Conclusion: QDs clearly labelled vasculature of hepatocellular carcinoma without uptake by tumor cells. MPM coupled with FLIM was successfully applied for the first time to visualize the disposition of QDs in liver cancer with subcellular resolution. QDs showed great potential as emerging tools in cancer diagnosis and monitoring treatment response by imaging tumor vasculature. No conflict of interest. 709 POSTER Surveillance of relapse with 18F-flurodeoxyglucose positron emission to-mography/computed tomography in diffuse large B-cell lymphoma after achieving complete remission with rituximab containing regimen R. Kim1 , K.H. Kim2 , J.S. Kim2 , J.H. Park2 , I.S. Choi2 . 1 Seoul National University Hospital, Internal Medicine, Seoul, South Korea; 2 Seoul National University Hospital Boramae Medical Center, Internal Medicine, Seoul, South Korea Background: In diffuse large B-cell lymphoma(DLBCL), the surveillance of relapse with 18 F-fluorodeoxygluocose positron emission tomography/ computed tomography(PET/CT) remains controversial. The purpose of this study was to evaluate the efficacy of PET/CT in surveillance of DLBCL relapse after achievement metabolic complete remission(mCR). Material and Methods: From 2005 to 2014, medical records of 67 consecutive DLBCL patients who achieved mCR after 6−8 cycles of R-CHOP were analyzed. Two surveillance strategies were descriptively compared: routine follow-up with computed tomography(CT) in combination with physical examination(P/E), routine follow-up with PET/CT including final assessment of any suspect PET/CT findings using other imaging modalities and/or biopsy. As an institutional protocol, most of patients underwent biannual PET/CT or CT after achievement of mCR, further scans were then carried out on an annual basis. PET/CT findings were reported as negative or positive for relapse. Patient informed consent was waived because of the retrospective design of the study. Results: Of a total of 67 patients, forty-five patients(67.2%) underwent surveillance with PET/CT(PET/CT group), 22 patients(32.8%) (no-PET/CT group) did not. Ten patients(14.9%) experienced relapse median 7 months (range 6.3–47.4 months) after mCR: 5 patients in PET/CT group, 5 patients in no-PET/CT group. In PET/CT group, a total of 110 follow-up PET/CT were performed. Seventysix of the follow-up PET/CTs(69.1%) were negative, and none of them confirmed relapse. On the other hand, 34 follow-up PET/CTs(30.9%) were positive, and additional 8 biopsies of suspicious lesion and 12 CT scans were required to confirm relapse. The sensitivity, specificity, positive predictive value(PPV), and negative predictive value of follow-up PET/CT were 100.0%, 73.8%, 20.6%, 100.0%, respectively. In no-PET/CT group, relapses were detected by CT scan for 3 patients, and by clinical symptom for 2 patients. Median time to progression(TTP) was 9.0 months(range 6.3–47.4 months) in PET/CT group, 8.9 months(range 6.8–10.9 months) in no-PET/CT group (P = 0.7540 by Mann–Whitney test). The total cost of surveillance was $5,900 per patients in PET/CT group, $4,000 per person in no-PET/CT group. Conclusion: Most of follow-up PET/CT was negative, and PPV of followup PET/CT was low. A half of relapses were detected by PET/CT, but
Abstracts they required additional diagnostic procedure, such as CT scan and/or biopsy, to confirm relapse. In addition, TTP was not statistically different between PET/CT group and no-PET/CT group. Otherwise, it costs about 1.5 times more to surveil relapse with follow-up PET/CT than with CT scan in combination with P/E. Therefore, we conclude that follow-up PET/CT is not superior to other follow-up modalities such as CT scan and P/E in detecting relapse of DLBCL. No conflict of interest. 710 POSTER Optomagnetic imaging spectroscopy in characterisation of cervical tissue and cancer detection using unstained sample approach M. Papic-Obradovic1 , B. Jeftic2 , A. Dragicevic2 , J. Muncan2 , L. Matija2 , D. Koruga2 . 1 Clinic of gynaecology and obstetrics Narodni Front, Department of science, research and education, Belgrade, Serbia; 2 University of Belgrade, Faculty of Mechanical Engineering, Department of biomedical engineering, Belgrade, Serbia Background: PAP test is based on stained samples using optical microscopy for characterisation and visual subjective approach for decision. The state of art of current method with sensitivity of 65% is not good enough. A new method with higher sensitivity and specificity is proposed. Material and Methods: For performance trail an optomagnetic imaging spectroscopy (OMIS), as a non-invasive method, was used to characterise a sample of 196 unstained smears. For each patient smears were taken from outer side of cervix and inner side − cervical canal. The OMIS is based on light-matter interaction and allows biophysical objective criteria of tissue characterisation. Results: To make classification between normal, cervical intraepithelial neoplasia and cancer stage, a Na¨ıve Bayes Cross Validation method was used. Normal − CIN1 state for other side of cervix has sensitivity of 94.7% and specificity of 90.5%, while for inner side (canal) results are 95.2% and 100%, respectively. However, for Normal − CIN4 state, sensitivity of 99.0% and specificity of 95.2% for outer side of cervix, while 99.0% and 90.7 are results for inner side (canal). Conclusions: Benefits of OMIS method are: (1) increased sensitivity and specificity (sensitivity 95.00%, specificity 94.44%), (2) time saving, because results of OMIS are provided within 10min, while current time of waiting for results is in the best cases 7 days, (3) cost reduction (there is no need for laboratory services, chemicals for staining, sample transport, and sample storage), and (4) reduced psychological pressure for women who have to wait for results. This study give both valid proof of concept and performance trail for optomagnetic imaging spectroscopy application in cervical tissue characterisation with significant cost reduction. No conflict of interest. 711 POSTER Ex vivo preclinical study of colon cancer using Opto-magnetic imaging spectroscopy and dual speed spinner magnetometer A. Dragicevic1 , Z. Krivokapic2 , I. Dimitrijevic2 , V. Markovic2 , L. Matija1 , D. Koruga1 . 1 University of Belgrade, Department of Biomedical Engineering, Faculty of Mechanical Engineering, Belgrade, Serbia; 2 University of Belgrade, Faculty of Medicine, First Surgical Hospital − Department of coloproctology, Belgrade, Serbia Background: According to data of GLOBOCAN (2012), colon cancer is still in the third place as one of the most common cancer worldwide. These data suggest a strong reason for ex vivo preclinical study which was done using a new non-invasive method for classification and diagnosis of colon cancer in order to improve and upgrade current methods for early detection. Material and Methods: Opto-magnetic imaging spectroscopy (OMIS) as a new imaging method for classification and early detection of colon cancer was used, as well as dual speed spinner magnetometer JR6 (AGICO s.r.o.), with accuracy 3pT, in order to measure difference of remanent magnetism between healthy and colon cancer tissue. OMIS method is based on lightmatter interaction and allows biophysical criteria in tissue characterization. Fifty-two samples of the colon tissue (26 healthy tissues and 26 cancer tissues) were inserted into separated, small, specially designed containers for magnetometer measuring, immediately after OMIS procedure, which takes 10 min/sample approximately. Results: The results show clear differences between healthy tissue and cancer, as well as between different types of colon cancer. Histograms of five types of colon cancer showed different wavelength difference and intensity of characteristic peaks obtained using OMIS method (average values of the activity in the domain of +8.96 n.a.u. in paramagnetic zone and −5.22 n.a.u. in diamagnetic zone for characteristic peaks and wavelength difference from 105 nm until 185 nm). Both JR-6A magnetometer (average
Abstracts they required additional diagnostic procedure, such as CT scan and/or biopsy, to confirm relapse. In addition, TTP was not statistically different between PET/CT group and no-PET/CT group. Otherwise, it costs about 1.5 times more to surveil relapse with follow-up PET/CT than with CT scan in combination with P/E. Therefore, we conclude that follow-up PET/CT is not superior to other follow-up modalities such as CT scan and P/E in detecting relapse of DLBCL. No conflict of interest. 710 POSTER Optomagnetic imaging spectroscopy in characterisation of cervical tissue and cancer detection using unstained sample approach M. Papic-Obradovic1 , B. Jeftic2 , A. Dragicevic2 , J. Muncan2 , L. Matija2 , D. Koruga2 . 1 Clinic of gynaecology and obstetrics Narodni Front, Department of science, research and education, Belgrade, Serbia; 2 University of Belgrade, Faculty of Mechanical Engineering, Department of biomedical engineering, Belgrade, Serbia Background: PAP test is based on stained samples using optical microscopy for characterisation and visual subjective approach for decision. The state of art of current method with sensitivity of 65% is not good enough. A new method with higher sensitivity and specificity is proposed. Material and Methods: For performance trail an optomagnetic imaging spectroscopy (OMIS), as a non-invasive method, was used to characterise a sample of 196 unstained smears. For each patient smears were taken from outer side of cervix and inner side − cervical canal. The OMIS is based on light-matter interaction and allows biophysical objective criteria of tissue characterisation. Results: To make classification between normal, cervical intraepithelial neoplasia and cancer stage, a Na¨ıve Bayes Cross Validation method was used. Normal − CIN1 state for other side of cervix has sensitivity of 94.7% and specificity of 90.5%, while for inner side (canal) results are 95.2% and 100%, respectively. However, for Normal − CIN4 state, sensitivity of 99.0% and specificity of 95.2% for outer side of cervix, while 99.0% and 90.7 are results for inner side (canal). Conclusions: Benefits of OMIS method are: (1) increased sensitivity and specificity (sensitivity 95.00%, specificity 94.44%), (2) time saving, because results of OMIS are provided within 10min, while current time of waiting for results is in the best cases 7 days, (3) cost reduction (there is no need for laboratory services, chemicals for staining, sample transport, and sample storage), and (4) reduced psychological pressure for women who have to wait for results. This study give both valid proof of concept and performance trail for optomagnetic imaging spectroscopy application in cervical tissue characterisation with significant cost reduction. No conflict of interest. 711 POSTER Ex vivo preclinical study of colon cancer using Opto-magnetic imaging spectroscopy and dual speed spinner magnetometer A. Dragicevic1 , Z. Krivokapic2 , I. Dimitrijevic2 , V. Markovic2 , L. Matija1 , D. Koruga1 . 1 University of Belgrade, Department of Biomedical Engineering, Faculty of Mechanical Engineering, Belgrade, Serbia; 2 University of Belgrade, Faculty of Medicine, First Surgical Hospital − Department of coloproctology, Belgrade, Serbia Background: According to data of GLOBOCAN (2012), colon cancer is still in the third place as one of the most common cancer worldwide. These data suggest a strong reason for ex vivo preclinical study which was done using a new non-invasive method for classification and diagnosis of colon cancer in order to improve and upgrade current methods for early detection. Material and Methods: Opto-magnetic imaging spectroscopy (OMIS) as a new imaging method for classification and early detection of colon cancer was used, as well as dual speed spinner magnetometer JR6 (AGICO s.r.o.), with accuracy 3pT, in order to measure difference of remanent magnetism between healthy and colon cancer tissue. OMIS method is based on lightmatter interaction and allows biophysical criteria in tissue characterization. Fifty-two samples of the colon tissue (26 healthy tissues and 26 cancer tissues) were inserted into separated, small, specially designed containers for magnetometer measuring, immediately after OMIS procedure, which takes 10 min/sample approximately. Results: The results show clear differences between healthy tissue and cancer, as well as between different types of colon cancer. Histograms of five types of colon cancer showed different wavelength difference and intensity of characteristic peaks obtained using OMIS method (average values of the activity in the domain of +8.96 n.a.u. in paramagnetic zone and −5.22 n.a.u. in diamagnetic zone for characteristic peaks and wavelength difference from 105 nm until 185 nm). Both JR-6A magnetometer (average