Yasuhiro Tsubosa

Alterations of chromosomal copy number during progression of diffuse-type gastric carcinomas: metaphase- and array-based comparative genomic hybridization analyses of multiple samples from individual tumours.

The application of comparative genomic hybridization (CGH) has led to the rapid accumulation of cytogenetic information on gastric carcinoma (GC), but there is little information on the time sequence of cytogenetic changes. In the present study, degenerate oligonucleotide‐primed polymerase chain reaction (DOP‐PCR) and CGH were applied to multiple samples microdissected from 19 diffuse‐type GCs including eight early cancers. Recurrent gains were detected at 8q, 3q, 7q, and 8p, and loss at 17p (in more than 50% of the cancers), the frequencies of which were fairly similar between the samples with (SIG) and those without (POR) abundant signet ring cells. Earlier stemline changes (8q+, 8p+, 1q+, 17p−, etc), with breakpoints that were common to all the samples, were discriminated from later sideline changes (2q+, 11q+, 17q−, 21q−, etc) in individual tumours. The changes were generally common to early and advanced cancers, except for 7p+, 15q+, 3p−, and 18q−, which were largely sideline changes and more frequently detected in advanced cancers (p < 0.05). Because the samples with 7p+ had a greater number of copy‐number changes than those without 7p+ (p < 0.01), 7p+ may play a role in tumour progression by acceleration of chromosomal instability. Fifteen different chromosomal loci with amplification were detected in ten cases, mostly as sideline changes in advanced cancers. By microarray‐based CGH, KRAS, MDM2, and FGFR2 were confirmed in the amplicons at 12p, 12q, and 10q, and FES at 15q26, for the first time in GC. These results support the notion that SIG and POR are of a genetically single lineage in both early and advanced diffuse‐type GC and that the majority of advanced cancers derive from early cancers through the accumulation of various sideline changes in addition to stemline changes. Copyright

Three-arm Phase III Trial Comparing Cisplatin Plus 5-FU (CF) Versus Docetaxel, Cisplatin Plus 5-FU (DCF) Versus Radiotherapy with CF (CF-RT) as Preoperative Therapy for Locally Advanced Esophageal Cancer (JCOG1109, NExT Study)

A three-arm Phase III trial was started in November 2012. Preoperative chemotherapy with cisplatin plus 5-fluorouracil is the current standard treatment for locally advanced esophageal cancer in Japan, while preoperative chemoradiotherapy with cisplatin plus 5-fluorouracil is the standard in Western countries. Preoperative chemotherapy with docetaxel, cisplatin plus 5-fluorouracil is another promising regimen. The purpose of this study is to confirm the superiority of docetaxel, cisplatin plus 5-fluorouracil over cisplatin plus 5-fluorouracil and the superiority of cisplatin plus 5-fluorouracil with chemoradiotherapy over cisplatin plus 5-fluorouracil as preoperative therapy for squamous cell carcinoma of esophagus. A total of 501 patients will be accrued from 41 Japanese institutions within 6.25 years. The primary endpoint is overall survival and the secondary endpoints include progression-free survival, %R0 resection, response rate, pathologic complete response rate and adverse events.

Randomized study of low-dose versus standard-dose chemoradiotherapy for unresectable esophageal squamous cell carcinoma (JCOG0303)

Low‐dose cisplatin and 5‐fluorouracil (LDPF) chemotherapy with daily radiotherapy (RT) is used as an alternative chemoradiotherapy regimen for locally advanced esophageal carcinoma. We evaluated whether RT plus LDPF chemotherapy had an advantage in terms of survival and/or toxicity over RT plus standard‐dose cisplatin and 5‐fluorouracil (SDPF) chemotherapy in this study. This multicenter trial included esophageal cancer patients with clinical T4 disease and/or unresectable regional lymph node metastasis. Patients were randomly assigned to receive RT (2 Gy/fraction, total dose of 60 Gy) with SDPF (arm A) or LDPF (arm B) chemotherapy. The primary endpoint was overall survival (OS). A total of 142 patients (arm A/B, 71/71) from 41 institutions were enrolled between April 2004 and September 2009. The OS hazard ratio in arm B versus arm A was 1.05 (80% confidence interval, 0.78–1.41). There were no differences in toxicities in either arm. Arm B was judged as not promising for further evaluation in the phase III setting. Thus, the Data and Safety Monitoring Committee recommended that the study be terminated. In the updated analyses, median OS and 3‐year OS were 13.1 months and 25.9%, respectively, for arm A and 14.4 months and 25.7%, respectively, for arm B. Daily RT plus LDPF chemotherapy did not qualify for further evaluation as a new treatment option for patients with locally advanced unresectable esophageal cancer. This study was registered at the UMIN Clinical Trials Registry as UMIN000000861.

Phase I/II trial of 2‐weekly docetaxel combined with cisplatin plus fluorouracil in metastatic esophageal cancer (JCOG0807)

We carried out a phase I/II trial of adding 2‐weekly docetaxel to cisplatin plus fluorouracil (CF) therapy (2‐weekly DCF regimen) in esophageal cancer patients to investigate its safety and antimetastatic activity. Patients received 2‐weekly docetaxel (30 mg/m2 [dose level (DL)1] or 40 mg/m2 [DL2] with a 3 + 3 design in phase I, on days 1 and 15) in combination with fixed‐dose CF (80 mg/m2 cisplatin, day 1; 800 mg/m2 fluorouracil, days 1–5) repeated every 4 weeks. The primary endpoint was dose‐limiting toxicity (DLT) in phase I and central peer review‐based response rate in phase II. At least 22 responders among 50 patients were required to satisfy the primary endpoint with a threshold of 35%. Sixty‐two patients were enrolled in phase I and II. In phase I, 10 patients were enrolled with DLT of 0/3 at DL1 and 2/7 in DL2. Considering DLT and treatment compliance, the recommended phase II dose was determined as DL1. In phase II, the response rate was 62% (P < 0.0001; 95% confidence interval, 48–75%); median overall survival and progression‐free survival were 11.1 and 5.8 months, respectively. Common grade 3/4 adverse events were neutropenia (25%), anemia (36%), hyponatremia (29%), anorexia (24%), and nausea (11%). No febrile neutropenia was observed. Pneumonitis caused treatment‐related death in one patient. The 2‐weekly DCF regimen showed promising antimetastatic activity and tolerability. A phase III study comparing this regimen with CF therapy is planned by the Japan Clinical Oncology Group. This study was registered at the UMIN Clinical Trials Registry as UMIN 000001737.

Cytogenetic heterogeneity and progression of esophageal squamous cell carcinoma.

It is widely believed that most human tumors, including esophageal squamous cell carcinoma (ESCC), arise through multistep genetic and cytogenetic alterations. The time sequence of these alterations, however, is still unknown. The present study was designed to differentiate common early changes from uncommon later ones with combined comparative genomic hybridization (CGH) and ploidy analyses in multiple or single samples of 12 ESCCs. We first demonstrated that the mean copy numbers of chromosomes 3 and 11, determined directly by fluorescence in situ hybridization, showed linear correlation with the mean copy numbers calculated from the G/R ratio of CGH and DNA ploidy (R(2)=0.714, P<0.0001). On this basis, we estimated the absolute copy numbers of chromosomal parts by applying the ploidy-dependent threshold criteria to the G/R ratio data after the criteria were corrected by the percentage of tumor cells in each sample. One-copy changes in the DNA-diploid stage may give large shifts of the G/R ratio, even after tetraploidization, whereas those after tetraploidization undergo small shift. Using the tumors with multiple samples, it was actually demonstrated that most of the gains common to the samples in individual tumors showed the large shifts. Though early changes varied from tumor to tumor in the nine informative cases, it was found that gains of 3q (5/7: number of cases with large-shift 3q+/total number of cases with 3q+), 8q (3/4), 11q13 (4/5), and 14q (3/4) were early events, while losses of 3p (2/8), 5q (1/5), 13q (1/5), and 21q (1/5), and gains of 1p (1/4) and Xq (1/4) were later events in progression of individual tumors.

A randomized Phase III trial of thoracoscopic versus open esophagectomy for thoracic esophageal cancer: Japan Clinical Oncology Group Study JCOG1409

A randomized Phase III study was commenced in May 2015 to confirm the non-inferiority of thoracoscopic esophagectomy to open esophagectomy in terms of overall survival for clinical Stage I-III esophageal cancer. A total of 300 patients will be accrued from Japanese institutions over 6 years. The primary endpoint is overall survival. The secondary endpoints are relapse-free survival, proportion of patients with R0 resection, proportion of patients who underwent re-operation, adverse events, postoperative respiratory function change, postoperative quality-of-life score (EORTC QLQ-C30), and proportion of patients who need conversion from thoracoscopic surgery to open surgery. This trial has been registered in the UMIN Clinical Trials Registry as UMIN000017628.

The efficacy of uracil DNA glycosylase pretreatment in amplicon-based massively parallel sequencing with DNA extracted from archived formalin-fixed paraffin-embedded esophageal cancer tissues

Advances in mutation testing for molecular-targeted cancer therapies have led to the increased use of archived formalin-fixed paraffin-embedded (FFPE) tumors. However, DNA extracted from FFPE tumors (FFPE DNA) is problematic for mutation testing, especially for amplicon-based massively parallel sequencing (MPS), owing to DNA fragmentation and artificial C:G > T:A single nucleotide variants (SNVs) caused by deamination of cytosine to uracil. Therefore, to reduce artificial C:G > T:A SNVs in amplicon-based MPS using FFPE DNA, we evaluated the efficacy of uracil DNA glycosylase (UDG) pretreatment, which can eliminate uracil-containing DNA molecules, with 126 archived FFPE esophageal cancer specimens. We also examined the association between the frequency of C:G > T:A SNVs and DNA quality, as assessed by a quantitative PCR (qPCR)-based assay. UDG pretreatment significantly lowered the frequency of C:G > T:A SNVs in highly fragmented DNA (by approximately 60%). This effect was not observed for good- to moderate-quality DNA, suggesting that a predictive assay (i.e., DNA quality assessment) needs to be performed prior to UDG pretreatment. These results suggest that UDG pretreatment is efficacious for mutation testing by amplicon-based MPS with fragmented DNA from FFPE samples.

Phase II study of chemoselection with docetaxel plus cisplatin and 5-fluorouracil induction chemotherapy and subsequent conversion surgery for locally advanced unresectable oesophageal cancer

Background:The standard treatment for locally advanced unresectable squamous cell carcinoma (SCC) of the oesophagus is chemoradiation with cisplatin and 5-fluorouracil (CF-RT). This multicentre phase II trial assessed the safety and efficacy of chemoselection with docetaxel plus cisplatin and 5-fluorouracil (DCF) induction chemotherapy (ICT) and subsequent conversion surgery (CS) for initially unresectable locally advanced SCC of the oesophagus.Methods:Patients with clinical T4 and/or unresectable supraclavicular lymph node metastasis were eligible. Treatment started with three cycles of DCF-ICT, followed by CS if resectable, or by CF-RT if unresectable. The resectability was re-evaluated at 30–40 Gy of CF-RT, followed by CS if resectable, or by completion of 60 Gy of CF-RT. If resectable after CF-RT, CS was performed. The primary end point was 1-year overall survival (OS).Results:From April 2013 to July 2014, 48 patients were enrolled. CS was performed in 41.7% (n=20), including DCF-CS (n=18), DCF-CF-RT40Gy-CS (n=1), and DCF-CF-RT60Gy-CS (n=1). R0 resection was confirmed in 19 patients (39.6%). Grade ⩾3 postoperative complications included one event each of recurrent laryngeal nerve palsy, lung infection, wound infection, pulmonary fistula, and dysphagia; but no serious postoperative complications were observed in patients undergoing CS. Clinical complete response after CF-RT was confirmed in 4 patients (8.3%). The estimated 1-year OS was 67.9% and lower limit of 80% confidence interval was 59.7%. There was one treatment-related death in patient receiving DCF-CF-RT60Gy.Conclusions:Chemoselection with DCF-ICT followed by CS as a multidisciplinary treatment strategy showed promising signs of tolerability and efficacy in patients with locally advanced unresectable SCC of the oesophagus.

CASE REPORT: Enzyme Histochemistry Is Useful to Assess Viability of Tumor Tissue After Microwave Coagulation Therapy (MCT): Metastatic Adenocarcinoma Treated by Lateral Segmentectomy After MCT

We report on a case of metastatic adenocarcinoma of liver that was removed and examined histochemically after microwave coagulation therapy (MCT). The patient was a 65-year-old woman who had a metastatic tumor in the liver (S3) after high anterior resection due to a rectal adenocarcinoma and received MCT against the tumor. One month after MCT, multiple metastatic tumors were detected by abdominal computed tomography (CT) scan. As it was difficult to control them by MCT alone, we performed lateral segmentectomy. To assess the effects of microwave ablation on cellular viability of metastatic tumor, we used enzyme histochemistry for acid phosphatase (AcP), which is positive in macrophages infiltrating in the tumor. In a part of the ablated area of resected liver, there was remaining neoplastic tissue of which the morphology was maintained in H&E staining. This was found to be microwave-fixed non-viable tissue because no enzyme activity of AcP was detected in the infiltrating macrophages. This case report suggests that enzyme histochemistry was useful to assess the effect of MCT, enabling us to distinguish fixed cells from viable cells.

Risk Factors for Esophageal Fistula Associated With Chemoradiotherapy for Locally Advanced Unresectable Esophageal Cancer: A Supplementary Analysis of JCOG0303

Abstract Esophageal fistula is a critical adverse event in patients treated with chemoradiotherapy (CRT) for locally advanced esophageal cancer. However, risk factors associated with esophageal fistula formation in patients receiving CRT have not yet been elucidated. We retrospectively analyzed data obtained from 140 patients who were enrolled in a phase II/III trial comparing low-dose cisplatin with standard-dose cisplatin administered in combination with 5-flurouracil and concomitant radiotherapy. Inclusion criteria were performance status (PS) 0 to 2 and histologically proven thoracic esophageal cancer clinically diagnosed as T4 and/or unresectable lymph node metastasis for which definitive CRT was applicable. Risk factors for esophageal fistula were examined with univariate analysis using Fisher exact test and multivariate analysis using logistic regression models. Esophageal fistula was observed in 31 patients (22%). Of these, 6 patients developed fistula during CRT. Median time interval between the date of CRT initiation and that of fistula diagnosis was 100 days (inter quartile range, 45–171). Esophageal stenosis was the only significant risk factor for esophageal fistula formation both in univariate (P = 0.026) and in multivariate analyses (odds ratio, 2.59; 95% confidence interval, 1.13–5.92, P = 0.025). Other clinicopathological factors, namely treatment arm, age, sex, PS, primary tumor location, T stage, lymph node invasion to adjacent organs, blood cell count, albumin level, and body mass index, were not risk factors fistula formation. Esophageal stenosis was a significant risk factor for esophageal fistula formation in patients treated with CRT for unresectable locally advanced thoracic esophageal squamous cell carcinoma.