Swisher, Stephen G.

AbstractBackground and ObjectivesPrecision medicine has altered the management of colorectal cancer (CRC). However, the concordance of mutational findings between primary CRC tumors and associated pulmonary metastases (PM) is not well‐described. This study aims to determine the concordance of genomic profiles between primary CRC and PM.MethodsPatients treated for colorectal PM at a single institution from 2000 to 2017 were identified. Mutational concordance was defined as either both wild‐type or both mutant alleles in lung and colorectal lesion; genes with opposing mutational profiles were reported as discordant.ResultsThirty‐eight patients met inclusion criteria, among whom KRAS, BRAF, NRAS, MET, RET, and PIK3CA were examined for concordance. High concordance was demonstrated among all evaluated genes, ranging from 86% (KRAS) to 100% concordance (NRAS, RET, and MET). De novo KRAS mutations were detected in the PM of 4 from 35 (11%) patients, 3 of whom had previously received anti‐epidermal growth factor receptor (EGFR) therapy. Evaluation of Cohen's κ statistic demonstrated moderate to perfect correlation among evaluated genes.ConclusionsBecause high intertumoral genomic homogeneity exists, it may be reasonable to use primary CRC mutational profiles to guide prognostication and targeted therapy for PM. However, the possibility of de novo KRAS‐mutant PM should be considered, particularly among patients previously treated with anti‐EGFR therapy.

7 Background: The organ preserving strategy of selective esophageal resection after definitive chemoradiation was evaluated in a multi-center, prospective Phase II trial. Methods: Treatment involved induction chemotherapy with 5-FU (650 mg/mg2/d), cisplatin (15 mg/mg2/d) and paclitaxel (200 mg/mg2/d) for 2 cycles followed by concurrent chemoradiation with 50.4 Gy (1.8 Gy/fx) and daily 5-FU (300 mg/mg2/d) with cisplatin (15 mg/mg2/d) over the first 5 days. Following definitive chemoradiation, pts were evaluated for residual locoregional disease with chest and abdominal CT scans, EUS and optional PET scans. If there was no suspected residual disease patients were observed and monitored serially for recurrent disease at 3 mos x 2, 6 mos x 3 and then yrly. Esophageal resection was considered only for pts with suspected residual or recurrent locoregional esophageal cancer that did not have systemic disease. Results: 43 pts from Sept 2003 to March 2006 with non-metastatic resectable esophageal cancer were entered from 19 sites to RTOG 0246. 41 pts were eligible for analysis. 29 pts (73%) were adenocarcinoma histology with pretreatment clinical stage T3 or greater in 31 pts (76%) and N1 in 29 pts (71%). Following induction chemotherapy and chemoradiation 3 pts (7.3%) died of treatment related deaths and 1 pt died of disease progression. 21 pts (51%) underwent surgical resection following chemoradiation because of suspected residual disease 17 pts (41%), pt choice (1) or recurrent locoregional disease 3 pts (7%). 1 pt died postoperatively from esophageal anastomotic leak. 11 pts (27%) are alive and free of disease 70 to 90 months after chemoradiation, of which 5 (12%) did not have esophagectomy. With a median follow-up of 6.7 yrs (for 16 alive pts), the estimated overall 2.5 and 5-year survival rates (95% CI) are 46.3% (30.7%-60.6%) and 36.6% (22.3%-51.0%). Conclusions: The long-term results from this multi-center, prospective Phase II trial demonstrates the efficacy of a selective surgical resection approach following definitive chemoradiation in a predominantly adenocarcinoma population of locoregionally advanced esophageal cancer. Clinical trial information: NCT00081289.

Abstract To better understand the molecular mechanisms behind esophageal adenocarcinoma (EAC) tumorigenesis, we used high-density single nucleotide polymorphism arrays to profile chromosomal aberrations at each of the four sequential progression stages, Barrett's metaplasia (BM), low-grade dysplasia (LGD), high-grade dysplasia (HGD), and EAC, in 101 patients. We observed a significant trend toward increasing loss of chromosomes with higher progression stage. For BM, LGD, HGD, and EAC, respectively, the average numbers of chromosome arms with loss per sample were 0.30, 3.21, 7.70, and 11.90 (P for trend = 4.82 × 10−7), and the mean percentages of single nucleotide polymorphisms with allele loss were 0.1%, 1.8%, 6.6%, and 17.2% (P for trend = 2.64 × 10−6). In LGD, loss of 3p14.2 (68.4%) and 16q23.1 (47.4%) was limited to narrow regions within the FHIT (3p14.2) and WWOX (16q23.1) genes, whereas loss of 9p21 (68.4%) occurred in larger regions. A significant increase in the loss of other chromosomal regions was seen in HGD and EAC. Loss of 17p (47.6%) was one of the most frequent events in EAC. Many recurrent small regions of chromosomal loss disrupted single genes, including FHIT, WWOX, RUNX1, KIF26B, MGC48628, PDE4D, C20orf133, GMDS, DMD, and PARK2, most of which are common fragile site regions in the human genome. However, RUNX1 at 21q22 seemed to be a potential tumor suppressor gene in EAC. Amplifications were less frequent than losses and mostly occurred in EAC. 8q24 (containing Myc) and 8p23.1 (containing CTSB) were the two most frequently amplified regions. In addition, a significant trend toward increasing amplification was associated with higher progression stage. Cancer Prev Res; 3(9); 1176–86. ©2010 AACR.