Core homologous recombination mutations and improved survival in nonpancreatic GI cancers

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Background: GI malignancies continue to be a major cause of cancer related deaths, despite advances in therapy options. In pancreatic cancer, the presence of homologous recombination mutations (HRM) has been shown to confer increased sensitivity to platinum chemotherapy. However, the role of HRM mutations in other GI cancers remains to be determined. The focus of this study is to evaluate the prognostic nature of core and noncore HRM in nonpancreatic GI cancers. Additionally, we aim to understand the predictive nature of these mutations related to platinum exposure. Methods: This was a retrospective review of patients at Moffitt Cancer Center with a primary stage IV nonpancreatic GI cancer treated with platinum therapy. All patients had next generation sequencing and were in the Clinical Genomics Action Committee database between 1/1/2013 and 11/1/2020. All patients had either a core HRM (BRCA1, BRCA2, PALB2) or noncore HRM (such as ATM, ATR, BARD1, BRIP1, FANCA, NBN, and RAD51). Patients were grouped into core HRM vs. noncore HRM. Response was stratified between responders (complete response and partial response) vs. non responders (stable disease and progressive disease), based on RECIST criteria. Progression free survival and overall survival were estimated using Kaplan-Meier method, and the log-rank test was used to assess the difference in progression free survival (PFS) and overall survival (OS) by HRM status and type of platinum therapy used. Results: There were 72 patients included in the study: the majority of patients were male (65.3%) and Caucasian (87.5%). Twenty-one (29.2%) patients had a core HRM and 51 (70.8%) had a noncore HRM. There was no significant difference in response rate between patients with core HRM and patients with noncore HRM for evaluable patients (n = 66): 20.0% of patients with core HRM vs. 21.7% of patients with noncore HRM demonstrated a response to platinum therapy (p = 0.41). An improved OS was noted for patients with core HRM vs. those with noncore HRM at 68.9 vs. 24.3 months (p = 0.019). An improved PFS was also seen in patients with core HRM at 10.4 months vs. 6.3 months with noncore HRM (p = 0.027). There was no difference in PFS based on type of platinum therapy used (oxaliplatin vs. carboplatin vs. cisplatin), while an improved OS was noted for patients treated with oxaliplatin vs. carboplatin vs. cisplatin at 43.1 vs. 28.2 vs. 16.0 months (p = 0.011). Conclusions: Our study demonstrated that in stage IV nonpancreatic GI malignancies treated with platinum therapy, patients with core HRM had a greater OS and PFS compared to those with noncore HRM, suggesting a potential prognostic and predictive role of these mutations. Further studies are needed to confirm our findings.

Association of BRAF V600E mutation with survival in patients with metastatic mismatch repair-deficient colorectal cancer

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Background: Colorectal cancer (CRC), while one of the most common cancer diagnoses, can behave heterogeneously based on molecular characteristics. A subset of patients (pts) with CRC are characterized with mismatch repair deficiency (MMR-d), these pts exhibit encouraging responses to immunotherapy. The predictive nature of various factors, such as BRAF status, age, and MMR-D protein loss type, have been investigated in pts with MMR-d CRC. However, the prognostic role of these factors has not been well established. The purpose of this study was to identify characteristics that influence survival in MMR-d mCRC. Methods: This study evaluated pts with MMR-d mCRC in the Flatiron database. Overall survival (OS) was determined from date of diagnosis of stage IV disease to date of death and stratified based on age greater than or less than 50 years, BRAF mutation status, RAS mutation status, and type of MMR gene loss. For statistical analysis, the Chi-Square test was implemented to determine the prognostic significance of clinical and molecular features. Univariate and multivariate analyses were determined through the Cox regression model. Results: There were 1,101 pts in the study. The majority of pts were older than 50 (79.7%), Caucasian (75%), and had ECOG 0-1 (83.4%). Among the 803 pts with known BRAF status, 44.3% (n=356) had BRAF V600E mutation and 55.7% (n=447) were BRAF wildtype. Pts with BRAF V600E mutation had OS of 18.9 months vs. 33.2 months for pts with wild type BRAF (HR 1.52, 95% CI: 1.25-1.86, p<0.001). Pts older than 50 had a lower median OS vs. those who were ≤50 at 21.4 months vs. 38.7 months (HR 1.66, 95% CI: 1.33-2.07, p<0.001). When comparing MSH2/MSH6 mutations to MLH1/PMS2, a trend towards improved OS was seen with median survival of 35.2 months vs. 22.7 months, respectively (HR 0.79, 95% CI: 0.61-1.02, p=0.067). On multivariate analysis, BRAF mutation and older age continued to be associated with differences in survival, while KRAS mutation and specific MMR gene loss did not. Conclusions: BRAF V600E mutation and age greater than 50 are associated with decreased survival for pts with MMR-D mCRC. KRAS mutations and specific MMR alterations are not associated with differences in survival.

Pathological outcomes of pancreatic adenocarcinoma (PA) after preoperative high biological effective dose (BED) magnetic resonance image-guided radiation therapy (MRgRT)

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Background: Pre-operative radiotherapy (RT) for PA has the potential to reduce positive surgical margin rates and increase pathologic tumor response, which has been associated with improved survival. Increasing the BED can improve local control and overall survival for patients with unresectable PA. Use of stereotactic body radiation therapy (SBRT) to achieve a higher BED has been limited by toxicity to adjacent radiosensitive structures, but this can be mitigated by MRgRT. We describe our use of MRgRT prior to potentially curative resection of localized PA. Methods: We performed a single institution retrospective analysis of all patients with localized PA who received high BED SBRT on the MR Linac followed by surgical resection with curative intent. Toxicity was evaluated according to Common Terminology Criteria for Adverse Events, version 5.0. Tumor response was evaluated according to the College of American Pathologists tumor regression grading criteria (CAP-TRG), ranging from CAP 0 indicating pathologic complete response to CAP grade 3 indicating no response. Ordinal logistic regression model was used to assess the association between time from RT to surgery and TRG. Follow up included MRI or CT scans at least every three months. Results: We analyzed 26 patients with borderline resectable (80.8%), locally advanced (11.5%), and resectable (7.7%) tumors who received high BED MRgRT followed by surgical resection. Median age at diagnosis was 68 years (34 - 86). Most patients received chemotherapy (80.8%) prior to RT, with 81% of these receiving FOLFINIRNOX and 19% receiving gemcitabine/nab-paclitaxel. All patients received MR-guided high BED SBRT to a median dose of 50 Gy (40 - 50) in 5 fractions. On-table adaptive replanning was performed in 88% of patients, with 74% having all 5 fractions adapted. No acute grade 2+ toxicity associated with RT was observed. The median time to resection was 50 days (37 – 115), and the procedure types included: Whipple (69%), distal (23%), or total pancreatectomy (8%). The R0 resection rate was 96% and no perioperative deaths occurred within 90 days. Complete (0) or near-complete (1) pathologic response was observed in 35% of cases and the time from RT to surgery was positively associated with TRG (R2= 0.22, p = 0.0003). The median follow-up after RT was 16.5 months (3.9- 26.2) during which 9 patients recurred, and 3 patients died of disease. The derived median progression-free survival from RT was 13.2 months. Conclusions: These initial pathology outcomes following high BED MR-guided SBRT are encouraging and suggest that the time from SBRT to surgical resection is associated with response. This finding is consistent with results from other preoperative GI tumor sites and results from prospective studies using high BED SBRT with MRI guidance in combined modality therapy against PA are eagerly awaited.

Efficacy of olaparib therapy in metastatic pancreatic ductal adenocarcinoma (PDAC) with homologous recombination deficiency (HRD)

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Background: Pancreatic cancer is one of the deadliest malignancies, with a 5 year OS of around 3%. Up to 3% of unselected patients (pts) with (PDAC) have the BRCA 1/2 mutation, while up to 15% possess HRD (ARID1A, ATM, BAP1, BARD1, BRIP1, CHEK1/2, FANCA, PALB2, RAD50, RAD51). PARP inhibitors, like olaparib, demonstrate clinical benefit in metastatic PDAC with BRCA mutations (mBRCA) and may have a role in those with HRD. The objective of this study is to determine the role of PARP inhibition in PDAC with HRD. Methods: This was a retrospective chart review of metastatic PDAC pts with germline (g) or somatic (s) mBRCA or HRD who received olaparib. An analysis of PFS and OS was performed for PDAC pts with mBRCA vs. HRD. Results: Forty-six pts with metastatic pancreatic cancer were identified to have mBRCA (n = 13) or HRD (n = 23) and received olaparib in our database. Median age was 73 years for mBRCA and 66 years for HRD. Five pts received olaparib as maintenance therapy after disease control with platinum: 2 mBRCA and 3 HRD pts. Six pts with mBRCA and 7 pts with HRD were platinum naïve prior to olaparib. Zero pts with mBRCA and 3 pts with HRD received olaparib after disease progression on platinum. The median (med)PFS for mBRCA vs. HRD was 6.1 months vs. 2.8 months (HR 0.5, 95% CI: 0.2-1.1, p = 0.07). The medOS for mBRCA vs. HRD was 7.7 vs. 5.3 months (HR 0.7, 95% CI: 0.2-1.9, p = 0.4). Of those with mBRCA who received olaparib, prior cisplatin exposure (n = 8) vs. cisplatin naïve (n = 5) led to medPFS of 6.1 vs. 7.8 months (HR 1.8, 95% CI 0.5-6.7, p = 0.3) and medOS of 6.8 months vs. 9.5 months (HR 1.5, 95% 0.3-6.4, p = 0.6). Six pts with HRD including gCHEK2 c.407T > C, gCHEK2 c.1461+1 G > A, gPALB2 gain (exon 11), sFANCI p.N1252S, sATM p.V2716A, sARID1A Q944fs*14 were noted to have disease control of at least 3 months on olaparib. Only one of these pts received olaparib as maintenance therapy after platinum. The medPFS was 6.1 months and medOS was not reached. One pt with HRD (sFANCI N1252S) had progressive disease on platinum prior to olaparib, but had stable disease > 5 months with olaparib. Conclusions: Our study suggests olaparib may have anticancer activity in PDAC with certain HRD. In addition, olaparib may have a role outside maintenance therapy in PDAC with mBRCA. Prospective studies are needed to confirm these findings.

Investigate the efficacy of immunotherapy for treatment of pancreatic adenocarcinoma (PDAC) with mismatch repair deficiency (dMMR)

415

Background: Immune checkpoint inhibitors (ICI) have been approved in solid tumors with dMMR. However, only limited data are available for PDAC with dMMR given the rarity of dMMR in PDAC. We evaluated efficacy of ICIs in PDAC with dMMR. Methods: Retrospective clinical and pathologic data were collected for patients (pts) with pancreatic adenocarcinoma from May 2017 to June 2020 at Moffitt cancer center. Results: We identified 10 pts with dMMR PDAC. The median age was 64.5 years (range: 42-86) and 4 pts were male. 4 pts had resectable disease, 3 had locally advanced and 3 had metastatic disease at initial diagnosis. MSH6 deficiency (def) was found in 2 cases, PMS2 def in 2, MLH/PMS2 def in 5, and MSH2/MSH6 in 1. 7 pts were treated with ICIs. 3 pts had locally advanced and 4 had metastatic disease when they started ICIs. 5 received Pembrolizumab (pem), 1 received ipilimumab/ nivolumab (ipi/nivo), and 1 received pem then ipi/nivo after progressive disease (PD) on pem. The median number of prior lines of chemotherapy was 1 (range 0-2). 6 pts were evaluable, and 1 had rapid disease progression after 1 dose of pem. Among 6 evaluable pts, 3 had an objective response (1: complete response and 2: partial response), and 2 had stable disease (SD). Median progression-free survival was 8.2 mo, and median overall survival was not reached with median follow-up (FU) of 6.8 mo. The median duration of response was not reached with a median FU of 22.6 mo. The pt with CR remained disease-free for up to 22 months. The pt whose treatment was switched to ipi/nivo after PD on pem achieved SD > 4mo on ipi/nivo. While on immunotherapy, one patient with ipi/nivo developed immunotherapy associated rash requiring systemic steroids, and another on pem developed hypothyroidism requiring levothyroxine. Conclusions: This series suggest ICIs can provide durable clinical efficacy in pts with dMMR PDAC.

Identification of Targetable Gene Fusions and Structural Rearrangements to Foster Precision Medicine in KRAS Wild-Type Pancreatic Cancer

It has recently been described that alternative oncogenic drivers may be found in KRAS wild-type (KRAS WT) pancreatic cancers. This study aimed to determine the incidence of targetable gene fusions present in KRAS WT pancreatic adenocarcinoma and response to targeted therapy.

METHODS

One hundred consecutive patients with pancreatic adenocarcinoma who underwent targeted next-generation sequencing using DNA sequencing with RNA sequencing (n = 47) or without RNA sequencing (n = 53) at a single institution were included in the study. The frequency and landscape of targetable fusions in KRAS WT pancreatic adenocarcinoma was characterized and compared with the frequency of fusions in KRAS-mutated (KRAS MUT) pancreatic adenocarcinoma. Results were validated in two independent cohorts using data from AACR GENIE (n = 1,252) and TCGA (n = 150). The clinical history of fusion-positive patients who received targeted treatment is described.

RESULTS

Pancreatic cancers from 13 of 100 patients (13%) were found to be KRAS WT. Targetable fusions were identified in 4/13 (31%) KRAS WT tumors compared with 0/87 (0%) KRAS MUT pancreatic adenocarcinomas (P = .0002). One patient with a novel MET fusion had a complete response to targeted therapy with crizotinib that is ongoing at 12+ months of treatment. In the validation cohorts, gene fusions were identified in 18/97 (19%) and 2/10 (20%) KRAS WT tumors reported in the AACR GENIE and TCGA cohorts, respectively.

CONCLUSION

Oncogene fusions are present in KRAS WT pancreatic adenocarcinomas at an increased frequency when compared with KRAS MUT pancreatic adenocarcinomas. As these fusions may be susceptible to targeted therapy, molecular analyses for the detection of fusions in KRAS WT pancreatic adenocarcinomas may warrant increased consideration.

The impact of census-tract socioeconomic status on survival in stage III colon cancer

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Background: Socioeconomic status (SES) has been associated with worse outcomes in stage III colon cancer. However, these studies have used large geographic areas (zip codes or counties) as a proxy for SES which may bias results. To overcome this challenge, we used a national database with census-tract level SES to assess the impact on cancer-specific (CSS) and overall survival (OS). Methods: Using the SEER Census-Tract Dataset from 2004-2015, we identified 8th edition AJCC stage III colon adenocarcinoma patients who underwent curative-intent surgery and initiated adjuvant chemotherapy. The predictor variable was census-tract level SES, consisting of 7 variables such as income, housing, and education. SES was analyzed as quartiles. Statistical analysis included chi square tests for association and Kaplan-Meier and Cox regression for survival analysis. Results: We identified 27,222 patients who met inclusion criteria. Lower SES was associated with younger age, Black or Hispanic race/ethnicity, Medicaid or uninsured status, higher T stage, <12 lymph nodes examined and lower grade tumors. Median CSS was not reached; the 25th percentile CSS time was 54 months for the lowest SES (LSES) quartile and 80 months for the highest (HSES). Median OS was 113 months for LSES and not reached for HSES. The 5-year CSS rate was 72.4% for the LSES quartile compared to 78.9% in the HSES (p<0.001). The 5-year OS rate was 66.5% for LSES and 74.6% in the HSES (p<0.001). After adjusting for potential confounders (age, sex, race, insurance, pathologic T and N stage and grade), LSES was associated with increased cancer-specific death relative to the HSES (HR 1.22; 95% CI [1.114-1.327]) Conclusions: This is the first study to evaluate CSS and OS in a national cohort of stage III colon cancer patients using a granular, standardized measure of SES. Despite receipt of guideline-based treatment, low SES remained a predictor of increased cancer-specific mortality. These data suggest that investigating treatment barriers beyond adjuvant therapy is needed to address colon cancer survival disparities. [Table: see text]

Predictors of recurrence and implications for overall survival in borderline resectable pancreatic cancer patients treated with total neoadjuvant therapy: A retrospective cohort study

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Background: Borderline resectable pancreatic ductal adenocarcinoma (BR PDAC) is a subset of pancreatic cancer with unique prognostic implications. A multimodality, neoadjuvant therapy (NAT) approach has known benefits such as downstaging tumors, reducing the risk of a positive margin, and treating micrometastatic disease. Patient selection and therapy sequencing are controversial owing to the high risk of recurrence. Therefore, we aimed to identify factors predicting recurrence and overall survival (OS) in BR PDAC patients undergoing NAT. Methods: We identified BR PDAC patients treated with NAT followed by surgery at Moffitt Cancer Center between 2008-2015. We evaluated clinical, demographic, and perioperative factors to identify predictors of recurrence and OS. Statistical analyses were performed with univariate and multivariable Cox regression models. Results: 117 patients with BR PDAC who received NAT were evaluated; 53 (45%) were female and 64 (55%) were male. Of those, 91 (78%) received gemcitabine/xeloda/taxotere and the remainder received other gemcitabine or 5FU regimens. 107 (91%) patients received neoadjuvant radiation, mainly 5-day dose painted SBRT. Post- NAT CA 19-9 normalized in 39 (33%) and 11 (9%) additional patients normalized after surgery. Pathologic treatment effect was appreciated in 85 (73%) patients and pathologic complete response (pCR) was seen in 18 (15%). 95 (81%) patients initiated adjuvant therapy. In multivariable analysis, the strongest predictor of recurrence was higher log(10) post-operative CA 19-9 (HR 2.29; 95% CI, 1.40-3.75). Time from initiation of NAT to surgery ≥ 5 months also predicted recurrence (HR 2.08; 95% CI, 1.16-3.72). In OS analysis, 71 patients had recurrence after multimodality treatment; 61 (86%) died and 10 (14%) were alive. In multivariable analysis, the strongest predictors of prolonged OS from recurrence were female gender (HR 0.47; 95% CI, 0.26-0.84) and presence of a treatment effect (HR 0.37; 95% CI, 0.15-0.93). Conclusions: We observed treatment effects and pCR comparable to other institutions, supporting a multimodality approach to BR PDAC. Higher post-operative CA 19-9 and time to surgery ≥ 5 months from initiation of NAT were associated with an increased risk of recurrence. These data suggest that timely receipt of surgery after completion of NAT may impact recurrence and OS in BR PDAC.

An intersectional investigation of race and sex on receipt of adjuvant chemotherapy in stage III colon cancer

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Background: Race and sex disparities exist for receipt of adjuvant chemotherapy (AC) for stage III colon cancer. However, most studies have not used an intersectional approach, which assesses the cumulative effects of different identities (e.g., Black women) instead of treating each as distinct, independent variables. Using this approach, we assessed the summative impact of these identities on receipt of AC for stage III colon cancer. Methods: The National Cancer Database was queried from 2004 to 2015 for patients who underwent surgery for stage III colon cancer and were healthy enough for AC. Receipt of AC was assessed chi-squared and multivariable logistic regression analyses. Results: 92,696 patients were identified. White patients had higher rates of care at community cancer centers. Black patients had higher rates of treatment at academic cancer programs (p < 0.001). Overall 83.5% received AC. Black males and females had higher rates of AC (86.5% and 86.2%, respectively) compared to White males and females (85.3% and 80.5%), respectively (p < 0.001). In adjusted analysis, Black males had the lowest odds of AC (OR 0.73), followed by Black females (OR 0.89) and White females (OR 0.91). When evaluated by age < 65 years and adjusting for potential confounders, Black men remained the least likely group to receive AC (OR 0.70). Black females had similar odds of receipt of AC (OR 0.99) and White females had increased odds (OR 1.22) relative to White males. Conclusions: Despite higher rates of treatment at academic centers, Black males and females had lower odds of receipt of AC after adjusting for confounders. Younger Black males persisted with the lowest odds of AC, although younger Black females had odds similar to younger White males. Additional research is necessary to identify drivers of these disparities and interventions to ameliorate them. [Table: see text]

Racial and ethnic disparities in a state-wide registry of patients with pancreatic cancer and an exploratory investigation of cancer cachexia as a contributor to observed inequities

Pancreatic cancer (PC) is characterized by racial/ethnic disparities and the debilitating muscle-wasting condition, cancer cachexia. Florida ranks second in the number of PC deaths and has a large and understudied minority population. We examined the primary hypothesis that PC incidence and mortality rates may be highest among Black Floridians and the secondary hypothesis that biological correlates of cancer cachexia may underlie disparities. PC incidence and mortality rates were estimated by race/ethnicity, gender, and county using publicly available state-wide cancer registry data that included approximately 2700 Black, 25 200 Non-Hispanic White (NHW), and 3300 Hispanic/Latino (H/L) Floridians diagnosed between 2004 and 2014. Blacks within Florida experienced a significantly (P < 0.05) higher incidence (12.5/100 000) and mortality (10.97/100 000) compared to NHW (incidence = 11.2/100 000; mortality = 10.3/100 000) and H/L (incidence = 9.6/100 000; mortality = 8.7/100 000), especially in rural counties. To investigate radiologic and blood-based correlates of cachexia, we leveraged data from a subset of patients evaluated at two geographically distinct Florida Cancer Centers. In Blacks compared to NHW matched on stage, markers of PC-induced cachexia were more frequent and included greater decreases in core musculature compared to corresponding healthy control patients (25.0% vs 10.1% lower), greater decreases in psoas musculature over time (10.5% vs 4.8% loss), lower baseline serum albumin levels (3.8 vs 4.0 gm/dL), and higher platelet counts (332.8 vs 268.7 k/UL). Together, these findings suggest for the first time that PC and cachexia may affect Blacks disproportionately. Given its nearly universal contribution to illness and PC-related deaths, the early diagnosis and treatment of cachexia may represent an avenue to improve health equity, quality of life, and survival.

A phase II study of TAS-102 in combination with ramucirumab in advanced, refractory gastric or gastroesophageal junction (GEJ) adenocarcinoma

TPS4149

Background: Patients with advanced gastric cancer experience a 5 year survival rate <10% even with multimodality therapy representing a clear unmet need for improved treatment. In advanced gastric and gastroesophageal junction (GEJ) adenocarcinoma, ramucirumab (a monoclonal antibody against VEGFR2) has demonstrated clinical activity and has been approved as second line therapy in combination with paclitaxel with a response rate of 28% and absolute overall survival benefit of 8 weeks when compared to placebo. However, there are many patients that cannot tolerate paclitaxel due to prior exposure to oxaliplatin causing neuropathy. Therefore, novel combinations with ramucirumab, is highly desirable. TAS-102 is an oral cytotoxic agent with two active components; trifluridine (TFD) which inhibits tumor cell growth by being incorporated into DNA during DNA synthesis and tipiracil (TPI) which inhibits the metabolism of TFD, thereby prolonging its ability to exert effect. TPI also inhibits platelet derived endothelial cell growth factor which plays a key role with VEGF in tumor angiogenesis. The combination of a cytotoxic agent with an antiangiogenic agent has demonstrated a significant anticancer activity in multiple cancers. In a recent Phase III study, TAS-102 significantly prolonged overall survival as compared to best supportive care in patients with GEJ and gastric cancers that had received at least 2 prior lines of treatment. We hypothesize that a combination of TAS-102 and ramucirumab might increase efficacy without causing unmanageable toxicity. Methods: This is a single institutional phase II single arm two-stage design trial using the combination of TAS-102 and ramucirumab in advanced, refractory gastric or GEJ adenocarcinoma. Eligible patients include those with histologically confirmed gastric or GEJ adenocarcinoma that have received at least 1 prior line of treatment with performance status 0 or 1 and preserved organ function. Ramucirumab will be administered 8mg/kg every 2 weeks and TAS-102 at doses of 35 mg/m2 twice daily. Each cycle length will be 28 days. The primary endpoint is 6 month OS and secondary endpoints are safety, objective response rate and PFS. Fifteen patients will be enrolled in the first stage. If ≥ 7 of the 15 are alive at 6 months, an additional 10 patients will be enrolled in the second phase. Enrollment is currently ongoing. Clinical trial information: NCT03686488.

Determining optimal follow up for patients with anal cancer following chemoradiation

689

Background: U.S. health care is increasingly defined by over expenditure and inefficiency. Optimizing patient follow-up is critical especially in cancers treated with high control rates. The objective of this study was to assess time to disease recurrence or toxicity in a cohort of patients with anal carcinoma in order to optimize patient care. Methods: 140 patients diagnosed with biopsy-proven, non-metastatic anal carcinoma, treated with chemoradiation utilizing IMRT, were identified from an institutional database at our high volume center. After IRB approval, a retrospective study was conducted that evaluated local recurrence (LR), distant metastasis (DM), overall survival (OS), and late ≥ grade three toxicity (LG3T) based on National Cancer Institute Common Terminology for Adverse Events version 4. Patients were followed post-treatment every three months for two years, every six months in years 3-5 then yearly thereafter with imaging per National Comprehensive Cancer Network recommendations. Results: Median age and follow up is 58 years and 27 months, respectively. Patients were staged based on AJCC 8th edition and 24 patients were stage I (17%), 55 stage II (39%) and 61 stage III (44%). The median radiation dose was 54 Gy (range: 40-62.5), and 11% of patients required a radiation break. The two year LC, DMFS, and OS were 93%, 94% and 89% and 5-year LC, DMFS, OS were 92%, 87% and 85% respectively. In total, there were 29 disease or treatment related events: LR occurred in nine patients, DM in 11 patients, and LG3T in nine patients. Overall, 62% of events occurred within year one and 77 % within two years. Stratified by event type, at two years 79% of LR, 64% of DM and 89% LG3T were identified. At the remaining follow-up points after 2 years there was an event incidence rate of 1.4%. Conclusions: The majority of recurrences/toxicities in patients diagnosed with non-metastatic anal carcinoma after chemoradiation occur within the first year, with 77% of any event occurring before year two. The data from individual time points suggest a reduction in follow-up during years 3-5 may provide adequate surveillance. Considering revisions of the current follow-up recommendations could maximize health care resources while also improving patient quality of life.

Molecular Modeling and Functional Analysis of Exome Sequencing–Derived Variants of Unknown Significance Identify a Novel, Constitutively Active FGFR2 Mutant in Cholangiocarcinoma

Purpose

Genomic testing has increased the quantity of information available to oncologists. Unfortunately, many identified sequence alterations are variants of unknown significance (VUSs), which thus limit the clinician’s ability to use these findings to inform treatment. We applied a combination of in silico prediction and molecular modeling tools and laboratory techniques to rapidly define actionable VUSs.

Materials and Methods

Exome sequencing was conducted on 308 tumors from various origins. Most single nucleotide alterations within gene coding regions were VUSs. These VUSs were filtered to identify a subset of therapeutically targetable genes that were predicted with in silico tools to be altered in function by their variant sequence. A subset of receptor tyrosine kinase VUSs was characterized by laboratory comparison of each VUS versus its wild-type counterpart in terms of expression and signaling activity.

Results

The study identified 4,327 point mutations of which 3,833 were VUSs. Filtering for mutations in genes that were therapeutically targetable and predicted to affect protein function reduced these to 522 VUSs of interest, including a large number of kinases. Ten receptor tyrosine kinase VUSs were selected to explore in the laboratory. Of these, seven were found to be functionally altered. Three VUSs (FGFR2 F276C, FGFR4 R78H, and KDR G539R) showed increased basal or ligand-stimulated ERK phosphorylation compared with their wild-type counterparts, which suggests that they support transformation. Treatment of a patient who carried FGFR2 F276C with an FGFR inhibitor resulted in significant and sustained tumor response with clinical benefit.

Conclusion

The findings demonstrate the feasibility of rapid identification of the biologic relevance of somatic mutations, which thus advances clinicians’ ability to make informed treatment decisions.

Squamous cell carcinoma of the urinary bladder: Systematic review of clinical characteristics and therapeutic approaches

OBJECTIVE

To highlight the current understanding of the epidemiology, clinicopathological characteristics, and management of squamous cell carcinoma (SCC) of the bladder, as it accounts for 2-5% of bladder tumours, with a focus on non-bilharzial-associated SCC (NB-SCC). The standard treatment for bladder SCC remains radical cystectomy (RC). We present an updated clinical profile of bladder SCC and a review of NB-SCC therapeutic approaches, including RC, neoadjuvant and adjuvant treatments, radiotherapy, chemotherapy, and immunotherapy.

METHODS

Using search terms relating to SCC, urinary bladder, and treatment modalities, we performed a search of the PubMed and Embase databases to identify NB-SCC treatment approaches and outcomes. Peer-reviewed English language reports from 1975 to present assessing SCC management were included. Two authors independently screened and extracted the data.

RESULTS

Of the 806 articles screened, 10 met the pre-defined inclusion criteria. RC was performed in seven of the 10 studies. Although radiotherapy alone yielded poor outcomes, preoperative radiotherapy and RC were associated with improved survival. There is little evidence supporting the use of chemotherapy in NB-SCC, and its efficacy in relation to RC is not known.

CONCLUSION

Based on current literature, there is insufficient evidence to provide a treatment recommendation for NB-SCC. Whilst RC is the standard of care, the role of preoperative radiotherapy should be revisited and compared to RC alone. Additional studies incorporating multimodal approaches, contemporary radiation techniques, and systemic therapies are warranted. Immunotherapy as a treatment for bladder SCC has yet to be investigated.

PD-1 and PD-L1 Expression in Renal Cell Carcinoma with Sarcomatoid Differentiation

Monoclonal antibodies that target the programmed death-1 (PD-1)-programmed death ligand-1 (PD-L1) axis have antitumor activity against multiple cancers. The presence of sarcomatoid differentiation in renal cell carcinoma (RCC) is associated with resistance to targeted therapy and poor responses to IL2 immunotherapy. Given the aggressive nature of RCC with sarcomatoid differentiation and the exclusion of sarcomatoid histology from metastatic RCC clinical trials, less is understood regarding selection of therapies. Here, we characterized the PD-1/PD-L1 axis in RCC with sarcomatoid differentiation. We directly compared two PD-L1 antibodies and found concordance of PD-L1 positivity in 89% of tested RCCs with sarcomatoid differentiation. Coexpression of PD-L1 on neoplastic cells and the presence of PD-1-positive tumor-infiltrating lymphocytes were identified in 50% (13 of 26) of RCCs with sarcomatoid differentiation. In contrast, only 1 of 29 clear cell RCCs (3%) had concurrent expression of PD-L1 and PD-1 (P = 0.002). Our study suggests that RCC with sarcomatoid differentiation may express PD-1/PD-L1 at a higher percentage than RCC without sarcomatoid differentiation, and patients with these tumors may be good candidates for treatment with anti-PD-1/PD-L1 therapies.

Perioperative complications after neoadjuvant chemotherapy and radical cystectomy for bladder cancer

INTRODUCTION

Few data on the perioperative outcomes of cystectomy after neoadjuvant chemotherapy (NAC) exist. In this study, we evaluated whether patients who had previously received NAC were at higher risk of developing perioperative complications.

MATERIALS AND METHODS

The National Surgical Quality Improvement Program (NSQIP) database was searched to identify cystectomies performed between January 1, 2005 and December 31, 2011. Of 1394 patients identified, about one-tenth (n = 122 [8.8%]) received NAC. A propensity-weighted comparative analysis of perioperative morbidity was conducted.

RESULTS

In unadjusted comparisons, patients undergoing cystectomy after NAC were more likely to have peripheral nerve deficits (1.6% [2/122] versus 0.2% [3/1272]; p = .01), blood transfusions (37.7% [46/122] versus 27.5% [350/1272]; p = .02), and unplanned readmissions (11.5% [14/122] versus 6.6% [84/1272]; p = .04), but were less likely to require hospitalization longer than 8 days (45.1% [55/122] versus 58.8% [748/1272]; p = .01). Propensity-weighted adjustments showed that cystectomy after NAC produced little increased risk of perioperative surgical complications except for peripheral nerve deficits (3.2% [4/122] versus 0.3% [3/1166]; propensity score-adjusted odds ratio [PS-OR], 13.1; 95% CI, 1.90-90.8; p = .01) and resulted in better rates of wound dehiscence (0.8% [1/122] versus 3.3% [38/1166]; PS-OR, 0.20; 95% CI, 0.04-0.89; p = .04) and sepsis (4.9% [6/122] versus 11.4% [134/1166]; PS-OR, 0.36; 95% CI, 0.17-0.76; p = .01). No differences in 30 day mortality were noted.

CONCLUSIONS

NAC is not associated with perioperative complications after cystectomy. As expected, there was an increase in peripheral nerve deficits in the neoadjuvant chemotherapy group, but this was likely due to the known neurotoxicity of the cisplatin agents.

Genome-wide profiling of histone 3 lysine 36 trimethylation in clear cell renal cell carcinoma

464

Background: Although the von Hippel-Lindau (VHL) tumor suppressor gene is mutated in 60% of ccRCC, deletion of VHL in mice is insufficient for tumorigenesis. Sequencing of ccRCC tumors identified mutations in SETD2, a histone H3 lysine 36 (H3K36) trimethyltransferase. We hypothesize that loss of SETD2 methyltransferase activity alters the genome wide pattern of H3K36 trimethylation (H3K36me3) in ccRCC, and contributes to the cancer phenotype. Methods: To generate a genome-wide profile of H3K36me3 in frozen nephrectomy samples and RCC cell lines, we optimized a chromatin immunoprecipitation (ChIP) protocol for the isolation of DNA associated with H3K36me3. H3K36me3 is associated with open chromatin and an H3K36me3-specific antibody was used for immunoprecipitation of endogenous H3K36me3-bound DNA. ChIP PCR primers were optimized for active genes, such as actin, glyceraldehyde-3-phosphate dehydrogenase (GAPDH) and a “gene desert” on chromosome 12 (negative control). ChIP libraries were then generated from 3 paired uninvolved kidney and RCC and 2 RCC cell lines. In order to identify H3K36Me3 upregulated regions in uninvolved kidney and RCC, reads from the ChIP sequencing were mapped to the human genome using Burrows-Wheeler Aligner and SICER algorithms. Results: Using ChIP PCR, we found that active genomic regions were enriched 15-30 fold over the negative controls indicating that the quality and yield of immunoprecipitated DNA/chromatin complexes from frozen tissue was sufficient for ChIP sequencing. A preliminary ChIP sequencing analysis of RCC cell lines and frozen ccRCC tissue indicates that H3K36me3 enriched DNA sequences were mapped to exons (31.3%) compared to introns (13.5%, p<0.001), consistent with the role of H3K36me3 in transcription. Conclusions: Genomic regions enriched for H3K36Me3 binding were identified from patient-derived tissue and RCC cell lines. Current efforts are focused on comparing the H3K36me3 profiles between matched tumor and uninvolved kidney ChIP libraries to generate a genome wide map of dysregulated H3K36me3 modifications.

B-lymphoblastic leukemia/lymphoma associated with t(8;13)(p11;q12)/ ZMYM2 (ZNF198)-FGFR1 : rare case and review of the literature

Myeloid and lymphoid neoplasms with fibroblastic growth factor receptor-1 (FGFR1) abnormalities originate from mutated pluripotent stem cells and have a heterogeneous clinical presentation. There are 12 identified partner genes commonly involved in FGFR1 translocation at an 8p11 breakpoint. In FGFR1-related neoplasms, T-lymphoblastic lymphoma with eosinophilia is the most common clinical scenario, whereas acute B-lymphoblastic leukemia/lymphoma (B-ALL/LBL) is rare. To date, only 7 cases of B-ALL/LBL with FGFR1 abnormalities have been reported. Here, we report an additional case of a 64-year-old gentleman with leukocytosis, eosinophilia and diffuse mediastinal and general lymphadenopathy. Bone marrow examination showed patchy infiltrates of immature precursors/blasts, along with myeloid/eosinophilic hyperplasia. Immunophenotyping confirmed increased B lymphoblasts (30-40%). Karyotyping revealed cytogenetic abnormalities, including t(8;13)(p11;q12)/ZMYM2 (ZNF198)-FGFR1 and trisomy 21. The patient did not respond to hyper-CVAD chemotherapy and within 4 months developed acute myelomonocytic leukemia and expired 11 months after the initial diagnosis. Similar cases from the literature are reviewed.

Impact of immunoglobulin heavy chain variable region mutational status on the outcome of patients with chronic lymphocytic leukemia harboring isolated 13q deletion

6608

Background: Several prognostic factors can predict the course of chronic lymphocytic leukemia (CLL). Among them, the IGVH mutational status and the presence of cytogenetic abnormalities are the strongest predictors of outcome. Mutated IGVH and deletion 13q independently confer a survival advantage. CLL patients with mutated IGVH in combination with deletion 13q have a better prognosis when compared to their unmutated IGVH counterparts. However, there is limited data on the outcome of patients harboring favorable deletion 13q and the unfavorable unmutated IGVH. This study aimed at identifying patients with these two indicators in order to obtain important prognostic information. Methods: We used the Moffitt Cancer Center Total Cancer Care (TCC) database to find patients with a diagnosis of CLL between January 1993 and December 2009. Individual charts were reviewed for demographic data and CLL cytogenetics, including IGVH mutation status and presence of deletion 13q. We analyzed the impact of having deletion 13q in combination with an unmutated IGVH on the overall survival (OS) for this subset of CLL patients using Kaplan Meier curves with SPSS statistical software. Results: 546 patients were identified during the aforementioned time period with a diagnosis of CLL. Median age was 62.5 years. 144 (26.4%) of these patients had IGVH and cytogenetic analysis available. 53 patients had 13q deletion as their sole genetic abnormality. Patients with unmutated IGVH and positive for deletion 13q were 19/53 (35.8%). Patients with mutated IGVH and positive for deletion 13q were 34/53 (64.2%). Patients with mutated IGVH and positive for deletion 13q had an OS of 17 years. While patients with unmutated IGVH and positive deletion 13q had a lower median OS of 12 years (91.2% vs 78.9%, p=0.05). Hazard ratio for patients with IGVH mutated and positive deletion 13q was 0.4, p=0.05. Conclusions: Mutated IGVH appears to be associated with improved OS in patients with isolated 13q deletion when compared to patients with unmutated IGVH and isolated 13q deletion. Further research is needed to assess these mutations in relation to other cytogenetic abnormalities in CLL.

Should age affect our treatment decisions for head and neck cancer?

5564

Background: Current opinion suggests elderly patients (pts) with head and neck cancer, those 65 or older, do not tolerate surgery, chemotherapy, or radiation as well as their younger counterparts. If this holds true, elderly pts may not be offered standard treatments to prevent assumed complications. Methods: A retrospective cohort study at our comprehensive cancer center was conducted of newly diagnosed pts with head and neck squamous cell carcinoma to explore differences in treatment-related complications between older and younger groups. We included data from the first 199 eligible pts (99 younger than 65 year old and 100 older than 65) evaluated between April 2009 and June 2010. Results: 79% of pts receiving treatment were male with a mean age of 54.9 and 71.6 years for the younger and older groups respectively. The older group had significantly more comorbidities (p < 0.001). The majority of older pts presented with oral cavity tumors (46%) while the oropharynx was the predominant site in the younger group (45%). 55% of younger and 49% of older pts presented with stage 4 disease across all sites. A total of 51 pts were p16 positive with no statistical differences between the groups. Surgery was the initial treatment for 57% of older pts (p < 0.008) while 46% of younger pts received concurrent chemotherapy and radiation as the primary treatment (p < 0.008). There was no statistically significant difference in surgical or radiation complications between the groups. Although most pts receiving chemotherapy experienced complications, older pts had slightly more (93% vs. 78%; p<0.031). The mean survival was 24.8 months with no statistical difference between groups. Significantly more pts in the older group, at last follow-up, were disease free (p < 0.012). Conclusions: The treatment of elderly pts with head and neck squamous cell carcinoma in our experience was congruent with that of younger pts. Elderly pts did not suffer more complications with surgery or radiation, however chemotherapy produced somewhat more complications in the elderly pts. Elderly pts did display less evidence of disease on follow-up. Age is always a consideration when treating individuals, but should not preclude the curative standard.

Incidence of second and secondary malignancies in patients with CLL: A single institution experience

6568

Background: Patients with chronic lymphocytic leukemia (CLL) have a higher incidence of second malignancies than the general population with one study showing the risk at 2.2 times the general popualtion. The increased incidence is thought to be due to immunosupression which results in decreased cell surveillance and proliferation of malignant cells. Our study aims to present the rate of second malignancies by cancer type in patients with CLL at our institution. Methods: The Moffitt Cancer Center Total Cancer Care (TCC) database was used to identify patients who had a diagnosis of CLL between January 1993-December 2009. Individual charts were reviewed to confirm the diagnosis of CLL, collect demographic data, and to assess for the presence of a second malignancy under an IRB approved protocol. A second malignancy was defined as another malignancy or transformation of CLL reported in the medical record. Second malignancy data was placed in three categories; skin cancers, solid tumor malignancy, and hematologic malignancy. Results: 546 CLL patients were included in the study. Median age was 62.5 years. 84 (43%) were Stage 0 and 62 (32%) were Stage 1 RAI at diagnosis indicating earlier disease. 266 (49%) patients had a second or secondary malignancy. A total of 304 cancers were identified. 14% of patients had more than one malignancy. Melanoma was identified in 44 (16.5%) patients and non-melanoma skin cancer was identified in 54 (20%). Lung cancer was identified as the most frequent solid tumor malignancy with 36 (13.5%) cases, followed by prostate (35), breast (21), colorectal (15), and bladder (14). 10 patients had a Richter’s transformation of their CLL. 26 patients developed either myelodysplastic syndrome or acute myelogenous leukemia. Conclusions: Second malignancies are frequent in CLL patients. Immunosupression, increased UV light exposure, longer life expectancy in low risk CLL, and tertiary cancer center referral bias are likely reasons for these increased rates. Further research is needed to identify the precise mechanism which cause patients with CLL to have higher rates of second malignancies and to identify if there is an increased risk of a specific type of malignancy in patients with CLL.