- Email: [email protected]
109. Search of Cancer Stem Cell in Hepatocellular Carcinoma
226 ASSOCIATION FOR ACADEMIC SURGERY AND SOCIETY OF UNIVERSITY SURGEONS—ABSTRACTS sults: There were 8 residents in the LT group and 7 residents in the GDLT. The table demonstrates the GDLT group performed better on most of the tasks compared the LT group (higher scores ⫽ better performance). Conclusions: GDLT should be utilized instead of LT. Future studies need to examine if GDLT translates into better operative technique and outcomes.
110. FOREIGN ABSTRACT ESSR. F. ESSR, ESSR, TBD, AL Abstract not available
111. FOREIGN ABSTRACT SARS. F. SARS, SARS, TBD, AL
TABLE
Abstract not available
GDLT vs. LT Scores Tasks
GDLT
LT
p value
Peg Exercise Run the Rope Pattern Cutting Clip & Cut Vessel Extracorporeal Knot Tying Intracorporeal Knot Tying Use of Suturing Device
185 249 223 109
160 225 188 105
p p p p
309
212
p ⬍ 0.0001
433
351
p ⬍ 0.0001
451
414
p ⫽ 0.14
⬍ ⬍ ⬍ ⬍
0.0001 0.0001 0.0001 0.02
109. SEARCH OF CANCER STEM CELL IN HEPATOCELLULAR CARCINOMA. Yukio Kamohara1, Naotsugu Haraguchi1, Koshi Mimori1, Fumiaki Tanaka1, Yutaka Inoue1, Masaki Mori1, Takashi Kanematsu2; 1Kyushu University, Beppu, Japan; 2Nagasaki University, Nagasaki, Japan Background and Aims: Recent evidence suggests that some solid cancers may originate from cancer stem cells. We have identified subset of candidate stem cells termed side population (SP) cells in Huh7, a hepatocellular carcinoma cell line (Stem Cells 2006). On the other hand, stem cells are considered to exist at G0 phase of cell cycle. In this study, we investigated the relationship between SP cells and G0 cells, and clarified the biological characteristics of G0 phase cells. Study Design: Huh7 cells were sorted by flow cytometry using Hoechst 33342 and pyronin Y. Then, the cells were divided into G0, G1, and G2/M phase, respectively, and also into SP and non-SP fractions. The cells were cultured under a low attached condition to obtain spheroid cell clusters, and SP and G0 cells were counted. The cells in each cell-cycle phase were extracted respectively, and analyzed with respect to DNA synthesis condition (Ki67), hepatocytic (albumin expression) or cholangiocytic (keratin19 expression) differentiations. Results: The proportion of each cell-cycle phase of the Huh7 cells was 0.7%, 63.8%, and 34.5%, in G0, G1, and G2/M, respectively. On the other hand, SP and non-SP fraction were recognized in 0.9% and 98.8%, respectively. Interestingly, the G0 phase cells were located at a neck of SP fraction. Under a condition of spheroid cell culture, the ratio of SP fraction and that of G0 fraction were significantly increased. The G0 cells showed negative Ki67 expression, weakly positive albumin expression, and positive keratin19 expression, whereas, the G1 and G2/M cells did positive Ki67 expression, albumin expression, but negative keratin19 expression. Conclusion: It is demonstrated that Huh7 cells in G0 phase were included in the SP fraction and that they showed less proliferation activity. These cells, however, showed bidirectional differentiation to hepatocyte and cholangiocyte lineages. The findings suggest the G0 cells of Huh7 are promising candidate of cancer stem cells in hepatocellular carcinoma.
112. FOREIGN ABSTRACT SRSSA. F. SRSSA, SRSSA, SRSSA, AL Abstract not available
CLINICAL TRIALS/OUTCOMES RESEARCH II: GENERAL SURGERY/ENDOCRINE 113. DEFINING THE CURRENT NEGATIVE APPENDECTOMY RATE: FOR WHOM IS COMPUTED TOMOGRAPHY (CT) SCANNING MAKING AN IMPACT? Patrick L. Wagner, Soumitra R. Eachempati, Kevin Soe, Jian Shou, Philip S. Barie; New York Hospital/Weill Cornell Medical Center, New York, NY Introduction: Historically, the negative appendectomy rate (NAR) for patients suspected of having acute appendicitis has exceeded 20%. The objective of this study was to define the current NAR with increased use of CT scanning and laparoscopy. We hypothesized that CT scanning would be associated with a lower NAR in defined population groups. Methods: We undertook a single-institution retrospective chart review of all appendectomies performed for suspicion of acute appendicitis over a seven-year period. Operative and pathology reports and clinical records were reviewed for each case and the NAR was calculated and stratified by gender. Characteristics of patients undergoing negative appendectomy were analyzed. Results were compared with an earlier study from the same institution over the period 1995-1999 (Surgery 128:145-52). Statistics: Fisher exact test, student t-test, linear regression; p⬍0.05. Results: 1,426 consecutive patients undergoing appendectomy between 2000-2006 were evaluated. The overall NAR was 7.6% (adults 7.5%), down from 16.3% over the period 1995-99 (p ⫽ 0.0001); the NAR was 5.0% in the final year of the study. Concurrently, the percentage of patients undergoing preoperative CT scanning increased from 32% to 95% (Pearson correlation coefficient 0.881, p ⬍ 0.01). Adults undergoing preoperative CT were less likely to have a negative appendectomy than those not undergoing preoperative CT scan (6.7% versus 13.8%, p ⫽ 0.007). This difference was significant among females (7.5% vs. 20%, p ⫽ 0.005) but not among males (5.8% vs. 9.9%, p ⫽ 0.21). No difference in the NAR was noted between adults undergoing laparoscopic (n ⫽ 1110, 7.2%) versus open (n ⫽ 90, 8.4%) appendectomy. Notably, patients undergoing negative appendectomy had a longer duration of symptoms at presentation (2.2 vs. 1.6 days, p ⫽ 0.0005) and a lower white blood cell count (10.2 vs. 12.5, p ⬍ 0.0001); whereas the groups did not differ with respect to age, gender, or temperature at presentation. Conclusions: In the largest single-institution study to date evaluating negative appendectomy, the NAR has decreased to 5.0%. Additionally, preoperative CT has become nearly universal but is only associated with a lower NAR among female patients. Further data are needed to determine whether male patients benefit from preoperative CT scanning.
110. FOREIGN ABSTRACT ESSR. F. ESSR, ESSR, TBD, AL Abstract not available
111. FOREIGN ABSTRACT SARS. F. SARS, SARS, TBD, AL
TABLE
Abstract not available
GDLT vs. LT Scores Tasks
GDLT
LT
p value
Peg Exercise Run the Rope Pattern Cutting Clip & Cut Vessel Extracorporeal Knot Tying Intracorporeal Knot Tying Use of Suturing Device
185 249 223 109
160 225 188 105
p p p p
309
212
p ⬍ 0.0001
433
351
p ⬍ 0.0001
451
414
p ⫽ 0.14
⬍ ⬍ ⬍ ⬍
0.0001 0.0001 0.0001 0.02
109. SEARCH OF CANCER STEM CELL IN HEPATOCELLULAR CARCINOMA. Yukio Kamohara1, Naotsugu Haraguchi1, Koshi Mimori1, Fumiaki Tanaka1, Yutaka Inoue1, Masaki Mori1, Takashi Kanematsu2; 1Kyushu University, Beppu, Japan; 2Nagasaki University, Nagasaki, Japan Background and Aims: Recent evidence suggests that some solid cancers may originate from cancer stem cells. We have identified subset of candidate stem cells termed side population (SP) cells in Huh7, a hepatocellular carcinoma cell line (Stem Cells 2006). On the other hand, stem cells are considered to exist at G0 phase of cell cycle. In this study, we investigated the relationship between SP cells and G0 cells, and clarified the biological characteristics of G0 phase cells. Study Design: Huh7 cells were sorted by flow cytometry using Hoechst 33342 and pyronin Y. Then, the cells were divided into G0, G1, and G2/M phase, respectively, and also into SP and non-SP fractions. The cells were cultured under a low attached condition to obtain spheroid cell clusters, and SP and G0 cells were counted. The cells in each cell-cycle phase were extracted respectively, and analyzed with respect to DNA synthesis condition (Ki67), hepatocytic (albumin expression) or cholangiocytic (keratin19 expression) differentiations. Results: The proportion of each cell-cycle phase of the Huh7 cells was 0.7%, 63.8%, and 34.5%, in G0, G1, and G2/M, respectively. On the other hand, SP and non-SP fraction were recognized in 0.9% and 98.8%, respectively. Interestingly, the G0 phase cells were located at a neck of SP fraction. Under a condition of spheroid cell culture, the ratio of SP fraction and that of G0 fraction were significantly increased. The G0 cells showed negative Ki67 expression, weakly positive albumin expression, and positive keratin19 expression, whereas, the G1 and G2/M cells did positive Ki67 expression, albumin expression, but negative keratin19 expression. Conclusion: It is demonstrated that Huh7 cells in G0 phase were included in the SP fraction and that they showed less proliferation activity. These cells, however, showed bidirectional differentiation to hepatocyte and cholangiocyte lineages. The findings suggest the G0 cells of Huh7 are promising candidate of cancer stem cells in hepatocellular carcinoma.
112. FOREIGN ABSTRACT SRSSA. F. SRSSA, SRSSA, SRSSA, AL Abstract not available
CLINICAL TRIALS/OUTCOMES RESEARCH II: GENERAL SURGERY/ENDOCRINE 113. DEFINING THE CURRENT NEGATIVE APPENDECTOMY RATE: FOR WHOM IS COMPUTED TOMOGRAPHY (CT) SCANNING MAKING AN IMPACT? Patrick L. Wagner, Soumitra R. Eachempati, Kevin Soe, Jian Shou, Philip S. Barie; New York Hospital/Weill Cornell Medical Center, New York, NY Introduction: Historically, the negative appendectomy rate (NAR) for patients suspected of having acute appendicitis has exceeded 20%. The objective of this study was to define the current NAR with increased use of CT scanning and laparoscopy. We hypothesized that CT scanning would be associated with a lower NAR in defined population groups. Methods: We undertook a single-institution retrospective chart review of all appendectomies performed for suspicion of acute appendicitis over a seven-year period. Operative and pathology reports and clinical records were reviewed for each case and the NAR was calculated and stratified by gender. Characteristics of patients undergoing negative appendectomy were analyzed. Results were compared with an earlier study from the same institution over the period 1995-1999 (Surgery 128:145-52). Statistics: Fisher exact test, student t-test, linear regression; p⬍0.05. Results: 1,426 consecutive patients undergoing appendectomy between 2000-2006 were evaluated. The overall NAR was 7.6% (adults 7.5%), down from 16.3% over the period 1995-99 (p ⫽ 0.0001); the NAR was 5.0% in the final year of the study. Concurrently, the percentage of patients undergoing preoperative CT scanning increased from 32% to 95% (Pearson correlation coefficient 0.881, p ⬍ 0.01). Adults undergoing preoperative CT were less likely to have a negative appendectomy than those not undergoing preoperative CT scan (6.7% versus 13.8%, p ⫽ 0.007). This difference was significant among females (7.5% vs. 20%, p ⫽ 0.005) but not among males (5.8% vs. 9.9%, p ⫽ 0.21). No difference in the NAR was noted between adults undergoing laparoscopic (n ⫽ 1110, 7.2%) versus open (n ⫽ 90, 8.4%) appendectomy. Notably, patients undergoing negative appendectomy had a longer duration of symptoms at presentation (2.2 vs. 1.6 days, p ⫽ 0.0005) and a lower white blood cell count (10.2 vs. 12.5, p ⬍ 0.0001); whereas the groups did not differ with respect to age, gender, or temperature at presentation. Conclusions: In the largest single-institution study to date evaluating negative appendectomy, the NAR has decreased to 5.0%. Additionally, preoperative CT has become nearly universal but is only associated with a lower NAR among female patients. Further data are needed to determine whether male patients benefit from preoperative CT scanning.