Abstract P1-05-30: Genomic and microenvironmental intra-tumor heterogeneity in DCIS

Intra-tumor heterogeneity drives neoplastic progression by supplying the fuel for natural selection among neoplastic cells. It also complicates screening and treatment of neoplasms. We hypothesize that the degree of intra-tumor heterogeneity in DCIS should predict which tumors are likely to become invasive and metastatic. We initiated a pilot project to test this hypothesis by comparing 9 cases of pure DCIS to 9 cases of DCIS with adjacent invasive disease. For each case, we sequenced the exome from two spatially distinct regions of DCIS as well as normal tissue taken from a lymph node with no tumor involvement. This required the development of new methods to extract high quality sequencing data from small amounts of DNA extracted from FFPE samples. We calculated the genetic divergence between the two tumor regions, defined as percent of the sequenced regions of the genome showing differences between the two samples that had sufficient sequencing coverage and quality scores for confident scoring. We also employed automated imaging analysis to score microenvironmental differences between the two tumor regions. These microenvironmental measures are based on ecological methods for measuring organismal interactions and habitats. We will present initial data on differences in phenotypic and genotypic intra-tumor heterogeneity comparing pure DCIS to DCIS associated with invasive breast cancer. Our methods can be readily translated to large tissue banks of FFPE samples from DCIS.

Citation Format: Fortunato A, King L, Mallo D, Kovacheva V, Yuan Y, Boddy A, Graham T, Aktipis A, Mardis ER, Hall A, Marks JR, Hwang S, Maley CC. Genomic and microenvironmental intra-tumor heterogeneity in DCIS [abstract]. In: Proceedings of the 2016 San Antonio Breast Cancer Symposium; 2016 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2017;77(4 Suppl):Abstract nr P1-05-30.

Abstract P2-04-19: Elucidating the tumor immune microenvironment phenotype in early stage untreated BRCA mutated breast cancer patients

Background: Increased stromal tumor infiltrating lymphocytes (TILs) are predictive and prognostic for improved outcomes from neoadjuvant or adjuvant chemotherapy in triple negative breast cancer. Increased tumor mutational burden may promote neoantigens causing immune system upregulation. Microsatellite instability in gastrointestinal cancer predicts for response to checkpoint inhibition and is associated with inherited cancer predisposition. The immune system response in BRCA mutated breast cancer has not been described. The purpose of this study is to assess tumor infiltrating immune cells in early stage breast cancer patients with and without BRCA gene mutations.

Methods: We retrospectively investigated 124 early stage breast cancer patients with BRCA mutations (n=62, BRCA+) and without BRCA mutations (n=62, BRCA WT). The %TILs was measured manually by H&E. Our control group consisted of age, stage, and receptor status matched early stage untreated breast cancer patients who were deemed BRCA WT by extended gene panel testing or were negative for BRCA 1/2 and had a posttest probability of harboring an autosomal dominant mutated gene of ≤ 1% using the Bayes-Mendel algorithm. We used a two-sample binomial arcsin approximation to detect a 20% difference in TILs between cohorts to attain 80% power with a one-side alpha of 0.05. Wilcoxon Rank-Sums test was used to compare differences in the central tendencies for continuous variables. We used the Nanostring PanCancer immune profiling panel to immunophenotype a portion of the BRCA+ and BRCA WT cohorts and used nSolver for quality control, normalization, and bioinformatics analyses.

Results: Here we report TILs from the first 21 patients of our study. Thirteen patients harbored BRCA mutations and eight patients did not. All patients were HER2 negative. Eight (61%) and four (50%) patients were hormone receptor positive (HR+) in the BRCA+ and BRCA WT cohorts, respectively. Median %TILs were not significantly different between the BRCA+ (15, range 0-70) and BRCA WT (17.5, range 5-60; p=0.7) groups. Median %TILs in the HR+/BRCA+ (12.5, range 0-50) and HR-/BRCA+ (15, range 5-70) cohorts were not statistically different when compared to HR+/BRCA WT (10, range 5-15; p=0.4) and HR-/BRCA WT (30, range 20-60; p=0.2) cohorts, respectively. There were 2 patients with lymphocyte predominant breast cancer (n=1, HR-/BRCA+; n=1, HR-/BRCA WT).

Conclusions: This is the first study to characterize TILs and a tumor immune microenvironment phenotype in early stage breast cancer patients with BRCA mutations. These results suggest harboring a BRCA mutation is not associated with increased TILs in early stage untreated breast cancer patients. This conclusion stayed true regardless of hormone receptor status. However, a trend of decreased TILs was seen in HR-/BRCA+ patients when compared to those with HR-/BRCA WT disease. Moreover, the median and range of TILs were higher in the HR+/BRCA+ group compared to the HR+/BRCA WT group. This suggests increased TILs may exist in some HR+ patients with a BRCA mutation. Further investigation of TILs and immune profiling of early stage untreated breast cancer patients with and without BRCA mutations is warranted.

Citation Format: Force J, Abbott S, Broadwater G, Kimmick G, Westbrook K, Hwang S, Kauff N, Stashko I, Weinhold K, Nair S, Hyslop T, Blackwell K, Castellar E, Marcom PK. Elucidating the tumor immune microenvironment phenotype in early stage untreated BRCA mutated breast cancer patients [abstract]. In: Proceedings of the 2016 San Antonio Breast Cancer Symposium; 2016 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2017;77(4 Suppl):Abstract nr P2-04-19.

Survival Benefit of Early Cancer Detection Through Regular Endoscopic Screening for De Novo Gastric and Colorectal Cancers in Korean Liver Transplant Recipients

BACKGROUND

De novo malignancy is not uncommon after liver transplantation (LT). Gastric cancer is one of the most common malignancies in both the Korean general population and LT recipients, and colorectal cancer prevalence is gradually increasing.

METHODS

Among 3690 adult recipients who underwent LT from January 1999 and December 2013, the screening patterns and prognosis of 26 cases of gastric cancer and 22 cases of colorectal cancer were analyzed.

RESULTS

For gastric cancer, the mean patient age was 54.6 ± 6.2 years at LT and 59.5 ± 6.7 years at cancer diagnosis, with a post-transplant interval of 60.2 ± 29.8 months. Patients were divided into regular (n = 18) and non-regular (n = 8) screening groups, with early cancer found in 14 and 0 patients; their 2-year survival rates after cancer diagnosis were 93.1% and 33.3% (P = .006), respectively. Endoscopic resection was successfully performed in 8 patients, all in the regular screening group. For colorectal cancer, the mean patient age was 53.3 ± 6.1 years at LT and 58.1 ± 6.7 years at cancer diagnosis, with a post-transplant interval of 54.3 ± 38.0 months. Patients were divided into regular (n = 19) and non-regular (n = 3) screening groups, with early cancer found in 12 and 0 patients; their 2-year survival rates after cancer diagnosis of 92.3% and 33.3% (P = .003), respectively. Endoscopic resection was successfully performed in 6 patients, all in the regular screening group.

CONCLUSIONS

LT recipients are strongly advised to undergo regular screening studies for various de novo malignancies, especially cancers common in the general population. Regular endoscopic screening contributes to the timely detection of gastric and colorectal cancers, improving post-treatment survival outcomes.

Liver transplantation for "very early" intrahepatic cholangiocarcinoma: International retrospective study supporting a prospective assessment

The presence of an intrahepatic cholangiocarcinoma (iCCA) in a cirrhotic liver is a contraindication for liver transplantation in most centers worldwide. Recent investigations have shown that "very early" iCCA (single tumors ≤2 cm) may have acceptable results after liver transplantation. This study further evaluates this finding in a larger international multicenter cohort. The study group was composed of those patients who were transplanted for hepatocellular carcinoma or decompensated cirrhosis and found to have an iCCA at explant pathology. Patients were divided into those with "very early" iCCA and those with "advanced" disease (single tumor >2 cm or multifocal disease). Between January 2000 and December 2013, 81 patients were found to have an iCCA at explant; 33 had separate nodules of iCCA and hepatocellular carcinoma, and 48 had only iCCA (study group). Within the study group, 15/48 (31%) constituted the "very early" iCCA group and 33/48 (69%) the "advanced" group. There were no significant differences between groups in preoperative characteristics. At explant, the median size of the largest tumor was larger in the "advanced" group (3.1 [2.5-4.4] versus 1.6 [1.5-1.8]). After a median follow-up of 35 (13.5-76.4) months, the 1-year, 3-year, and 5-year cumulative risks of recurrence were, respectively, 7%, 18%, and 18% in the very early iCCA group versus 30%, 47%, and 61% in the advanced iCCA group, P = 0.01. The 1-year, 3-year, and 5-year actuarial survival rates were, respectively, 93%, 84%, and 65% in the very early iCCA group versus 79%, 50%, and 45% in the advanced iCCA group, P = 0.02.

CONCLUSION

Patients with cirrhosis and very early iCCA may become candidates for liver transplantation; a prospective multicenter clinical trial is needed to further confirm these results. (Hepatology 2016;64:1178-1188).

Donor Safety and Recipient Liver Function After Right-Lobe Liver Transplantation From Living Donors With Gilbert Syndrome

BACKGROUND

Donor safety is the most important aspect in living-donor liver transplantation (LDLT). Gilbert syndrome is an autosomal recessive condition that is a common cause of isolated unconjugated hyperbilirubinemia, and its prevalence is not negligibly low in the general population. This study intended to assess donor safety and recipient liver function after LDLT with the use of right liver grafts from living donors with Gilbert syndrome.

METHODS

Among 2,140 right liver transplantations performed from January 2002 to December 20113 at our institution, we identified 12 living donors (0.6%) who showed a preoperative serum total bilirubin level of ≥2 mg/dL. These donors were clinically diagnosed with Gilbert syndrome. The clinical outcomes of these donors and their recipients were analyzed retrospectively.

RESULTS

The mean donor age was 24.6 ± 7.1 years, and 11 donors were male. All subjects met the preoperative evaluation conditions for right liver donation except for the level of unconjugated hyperbilirubinemia. The mean serum total bilirubin level of the donors was 2.23 ± 0.20 mg/dL before and 1.79 ± 0.61 mg/dL 1 year after right liver donation. The preoperative donor direct bilirubin level was 0.43 ± 0.19 mg/dL. The preoperative indocyanine green retention rate at 15 minutes was 8.2 ± 2.8%. All donors and recipients recovered uneventfully and were alive at the time of writing. The recipient serum total bilirubin level was 1.29 ± 0.47 mg/dL 1 year after LDLT.

CONCLUSIONS

We suggest that LDLT with living donors with Gilbert syndrome can be safely performed, but that a meticulous preoperative evaluation is vital to maximize donor safety.

Comparison of Muscle Fiber and Meat Quality Characteristics in Different Japanese Quail Lines

The aim of this study was to compare the growth performance, fiber characteristics of the pectoralis major muscle, and meat quality characteristics in the heavy weight (HW) and random bred control (RBC) quail lines and genders. The HW male exhibited more than two times greater body (245.7 vs 96.1 g, p<0.05) and pectoralis major muscle (PMW; 37.1 vs 11.1 g, p<0.05) weights compared to the RBC female. This growth performance in the HW line was associated with a greater muscle fiber area (1,502 vs 663.0 μm², p<0.001) compared to the RBC line. Greater muscle mass of the HW male was accompanied by a higher percentage of type IIB fiber compared to the HW female (64.0% vs 51.0%, p<0.05). However, muscle fiber hyperplasia (increase in fiber number) has had a somewhat limited effect on PMW between the two lines. On the other hand, the HW line harboring a higher proportion of type IIB fiber showed rapid pH decline at the early postmortem period (6.23 vs 6.41, p<0.05) and lighter meat surface (53.5 vs 47.3, p<0.05) compared to the RBC line harboring a lower proportion of type IIB fiber. There were no significant differences observed in the measurement of water-holding capacity including drip loss (2.74% vs 3.07%, p>0.05) and cooking loss (21.9% vs 20.4%, p>0.05) between the HW and RBC lines. Therefore, the HW quail line developed by selection from the RBC quail, was slightly different in the meat quality characteristics compared to the RBC line, and a marked difference was found in growth performance between the two quail lines.

Mild heat stress enhances differentiation and proliferation of Japanese quail myoblasts and enhances slow muscle fiber characteristics

The objective of this study was to investigate the effect of mild heat stress on muscle fiber hyperplastic and hypertrophic growth in quail primary myogenic cells to better understand the mechanisms leading to increased skeletal muscle development in avian embryos incubated at a higher temperature. Compared to control cultures maintained at 37°C, incubation at 39°C enhanced myotube length (P < 0.01) and diameter (P < 0.001) at 3 days after differentiation (D3). This enlargement of the myotubes incubated at 39°C can be explained by differences in the fusion index (56.7 vs. 46.2%, P < 0.05) and nuclei number per myotube (18.1 vs. 10.8, P < 0.001) compared to the control cells at D3. Additionally, a higher density of myotubes at D3 in cultures exposed to a higher temperature were related to higher levels of Pax-7 (P < 0.05) compared to the control cells incubated continuously at 37°C. These results indicated a higher proliferative capacity in cells exposed to mild heat stress compared to the control cells. On the other hand, mild heat stress enhanced protein levels of slow myosin heavy chain isoform (P < 0.01) and cytochrome c oxidase subunit IV (P < 0.01) compared to the control cells at D3. These discrepancies in protein expression indicated maintenance of slow muscle fiber type characteristics in myotubes incubated at 39°C. Our results suggest that mild heat stress plays a significant role in myogenic mechanisms related to muscle mass and development.

Abstract S3-06: Treatment outcomes in patients with invasive breast cancer treated with neoadjuvant systemic therapy and breast MR imaging: Results of a secondary analysis of TBCRC 017

Background:Neoadjuvant chemotherapy (NCT) is used frequently to downstage locally advanced tumors and facilitate breast conservation. However, we have previously reported that achievement of radiographic complete response (rCR) or pathologic complete response (pCR) does not impact choice of surgery for many patients. This secondary analysis reports treatment outcomes across 9 NCI comprehensive cancer centers in women receiving both NCT and breast MR imaging to assess whether treatment outcomes among women receiving NCT differs according to choice of locoregional treatment.

Methods:1077 women from 9 institutions were retrospectively identified as having undergone NCT with MR imaging obtained both before and after systemic treatment. Systemic treatment regimen was not prespecified, but receipt of at least 80% of all planned cycles was required prior to final MR imaging. We performed a univariate analysis as well as a multivariable Cox proportional hazard regression to identify covariates associated with overall survival (OS), disease-free survival (DFS) and time to recurrence (TTR). rCR was defined as no residual enhancement on post-treatment breast MRI.

Results:1077 patients diagnosed and treated with NCT for stage I-III invasive breast cancer from January 1, 2002 to June 16, 2014 were analyzed for all endpoints. Median follow-up was 4.2 years, (range 0.1 to 13 years). Median age of the cohort was 50 years, (range 19-87 years). 473 (43.9%) had ER(+) and/or PR(+)/HER2(-) disease, 348 (32.3%) had HER2(+) disease, and 256 (23.8%) had ER(-)/PR(-)/HER2(-) (triple negative) disease. Mastectomy or breast conserving therapy (BCT) was recorded as the definitive surgery in 675 (62.7%) and 402 (37.3%) of patients, respectively. Radiation receipt was confirmed in 84.1% of BCT and 68.3% of mastectomy patients. Overall there were 134 recurrences, 168 disease events and 89 deaths. Among patients with pCR, there were 7/161 (7.2%) recurrences in those undergoing mastectomy and 6/143 (5.1%) in those undergoing lumpectomy (p=0.81). Among patients who achieved an rCR, there were recurrences in 5% of those undergoing mastectomy and 2.9% in those undergoing lumpectomy (p=0.53). In multivariable analysis of the entire cohort, only clinical stage, ER status and pCR remained independently associated with DFS. Notably, subset analysis showed that lumpectomy was independently associated with improved TTR (HR 0.40; 95% CI 0.17-0.97) in the triple negative group only, but this did not translate into improved DFS with lumpectomy in this group. Radiographic CR as determined by breast MRI accurately predicted presence or absence of pCR in 74% of cases, but was not independently associated with DFS, OS or TTP.

Conclusions:Among a contemporary cohort of women receiving neoadjuvant systemic therapy and breast MR imaging at 9 NCI designated cancer centers, type of surgery did not impact DFS, OS or TTP. The only exception was found in the triple negative group in which the lumpectomy group had a more favorable TTP compared to the mastectomy group. These findings provide additional evidence that in women who are appropriate candidates for lumpectomy after NCT, BCT does not compromise long-term cancer outcomes.

Citation Format: De Los Santos J, Hyslop T, Alvarado M, Forero A, Golshan M, Hieken T, Horton J, Hudis C, McGuire K, Meric-Bernstam F, Nanda R, Zagar T, Hwang S. Treatment outcomes in patients with invasive breast cancer treated with neoadjuvant systemic therapy and breast MR imaging: Results of a secondary analysis of TBCRC 017. [abstract]. In: Proceedings of the Thirty-Eighth Annual CTRC-AACR San Antonio Breast Cancer Symposium: 2015 Dec 8-12; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2016;76(4 Suppl):Abstract nr S3-06.

Intraoperative factors associated with delayed recovery of liver function after hepatectomy: analysis of 1969 living donors

BACKGROUND

The safety of healthy living donors who are undergoing hepatic resection is a primary concern. We aimed to identify intraoperative anaesthetic and surgical factors associated with delayed recovery of liver function after hepatectomy in living donors.

METHODS

We retrospectively analysed 1969 living donors who underwent hepatectomy for living donor liver transplantation. Delayed recovery of hepatic function was defined by increases in international normalised ratio of prothrombin time and concomitant hyperbilirubinaemia on or after post-operative day 5. Univariate and multivariate logistic regression analyses were performed to determine the factors associated with delayed recovery of hepatic function after living donor hepatectomy.

RESULTS

Delayed recovery of liver function after donor hepatectomy was observed in 213 (10.8%) donors. Univariate logistic regression analysis showed that sevoflurane anaesthesia, synthetic colloid, donor age, body mass index, fatty change and remnant liver volume were significant factors for prediction of delayed recovery of hepatic function. Multivariate logistic regression analysis showed that independent factors significantly associated with delayed recovery of liver function after donor hepatectomy were sevoflurane anaesthesia (odds ratio = 3.514, P < 0.001), synthetic colloid (odds ratio = 1.045, P = 0.033), donor age (odds ratio = 0.970, P = 0.003), female gender (odds ratio = 1.512, P = 0.014) and remnant liver volume (odds ratio = 0.963, P < 0.001).

CONCLUSIONS

Anaesthesia with sevoflurane was an independent factor in predicting delayed recovery of hepatic function after donor hepatectomy. Although synthetic colloid may be associated with delayed recovery of hepatic function after donor hepatectomy, further study is required. These results can provide useful information on perioperative management of living liver donors.

ABO-Incompatible Adult Living Donor Liver Transplantation Under the Desensitization Protocol With Rituximab

ABO incompatibility is no longer considered a contraindication for adult living donor liver transplantation (ALDLT) due to various strategies to overcome the ABO blood group barrier. We report the largest single-center experience of ABO-incompatible (ABOi) ALDLT in 235 adult patients. The desensitization protocol included a single dose of rituximab and total plasma exchange. In addition, local graft infusion therapy, cyclophosphamide, or splenectomy was used for a certain time period, but these treatments were eventually discontinued due to adverse events. There were three cases (1.3%) of in-hospital mortality. The cumulative 3-year graft and patient survival rates were 89.2% and 92.3%, respectively, and were comparable to those of the ABO-compatible group (n = 1301). Despite promising survival outcomes, 17 patients (7.2%) experienced antibody-mediated rejection that manifested as diffuse intrahepatic biliary stricture; six cases required retransplantation, and three patients died. ABOi ALDLT is a feasible method for expanding a living liver donor pool, but the efficacy of the desensitization protocol in targeting B cell immunity should be optimized.

Liver transplantation in Korea: past, present, and future

PURPOSE

This study reviewed the past and present status of liver transplantation (LT) and outlooks for the future of LT in Korea.

METHOD

The first LT in Korea was successfully performed using a deceased donor graft in 1988. Pediatric and adult living donor liver transplantations (LDLTs) were initiated in 1994 and 1997, respectively. From 1988 to 2013, 10,581 LTs were performed at 40 centers, whereas LDLT accounted for 76.5% of all LTs.

RESULTS

In the early 1990s, the deceased organ donation rate was less than 1.5 per million population (PMP) per year, but it increased to 5 PMP beginning in 2008. Despite the increasing number of deceased donor liver transplantations (DDLTs), high prevalence of hepatitis B virus (HBV)-induced cirrhosis and hepatocellular carcinoma (HCC) has provoked persistent performance of adult LDLT with technical advancement including middle hepatic vein (MHV) reconstruction of right lobe graft and dual graft LDLT with 1 nationwide donor mortality.

CONCLUSION

The number of LTs in Korea in 2010 was 23.2 PMP (1042 LTs/45 million population), lower than 23.5 PMP of Spain, but higher than 20 PMP of the United States. However, future LT numbers may decrease because of lowering the HBV carrier rate (neonatal HBV universal vaccination began in 1992), new potent anti-HBV agents, and lowest birth rate (1.22 children per family) with a decrease of potential live donors.

Correlation between risk of hepatitis B virus recurrence and tissue expression of covalently closed circular DNA in living donor liver transplant recipients treated with high-dose hepatitis B immunoglobulin

BACKGROUND AND AIMS

Despite the application of prophylaxis, the risk of hepatitis B virus (HBV) recurrence remains. However, actual mechanism(s) and definite risk factor(s) are obscure. The present study examined the correlation between the HBV load in liver explants and post-liver transplant (OLT) HBV recurrence.

METHODS

HBV DNA was extracted from liver tissue taken from 50 living donor OLT (LDLT) patients using the QuickGene DNA Tissue Kit S (Fujifilm, Tokyo, Japan) and subjected to real-time polymerase chain reaction with the following primers: 5'-CACATGGCCTCCAAGGAGTAA-3' (forward primer) and 5'-TGAGGGTCTCTCTCTTCCTCTTGT-3' (reverse primer). To prevent HBV infection, patients were treated daily with high-dose (10,000 IU) hepatitis B immunoglobulin (HBIG) for the first week after LDLT. They then received weekly doses for the next month and then monthly doses for ≤1 year. If the anti-hepatitis surface antigen antibody titer was <1,000 IU/L, an antiviral agent (AVA) was added to the regimen.

RESULTS

The mean (±SD) tissue HBV DNA and covalently closed circular DNA (cccDNA) loads were -0.8 ± 1.2 (range, -2.9 to 2.6) and -2.3 ± 1.1 (range, -4.6 to 0.6) log10 copies/cell, respectively. There was a significant correlation between serum and tissue HBV DNA (r = 0.65; P = .00) and cccDNA concentrations (r = 0.55; P = .00). Six patients suffered HBV recurrence and 9 required additional AVA. There was no direct correlation between HBV recurrence and tissue cccDNA concentration. However, the concentration of cccDNA was significantly greater those patients suffering recurrence and receiving AVA treatment (high-risk group).

CONCLUSION

High tissue cccDNA concentrations may be a risk factor for HBV recurrence despite high-dose HBIG prophylaxis.

Ashkin-Teller model and diverse opinion phase transitions on multiplex networks

Multiplex networks (MNs) have become a platform of recent research in network sciences because networks in many real-world systems interact and function together. One of the main scientific issues in MNs is how the interdependence changes the emerging patterns or phase transitions. Until now, studies of such an issue have concentrated on cluster-breakdown phenomena, aiming to understand the resilience of the system under random failures of edges. These studies have revealed that various phase transition (PT) types emerge in MNs. However, such studies are rather limited to percolation-related problems, i.e., the limit q→1 of the q-state Potts model. Thus, a systematic study of opinion formation in social networks with the effect of interdependence between different social communities, which may be seen as the study of the emerging pattern of the Ising model on MNs, is needed. Here we study a well-known spin model called the Ashkin-Teller (AT) model in scale-free networks. The AT model can be regarded as a model for interacting systems between two species of Ising spins placed on respective layers in double-layer networks. Our study shows that, depending on the interlayer coupling strength and a network topology, unconventional PT patterns can also emerge in interaction-based phenomena: continuous, discontinuous, successive, and mixed-order PTs and a continuous PT not satisfying the scaling relation. The origins of such rich PT patterns are elucidated in the framework of Landau-Ginzburg theory.