Use of deep learning to evaluate tumor microenvironmental features for prediction of colon cancer recurrence

Deep learning may detect biologically important signals embedded in tumor morphologic features that confer distinct prognoses. Tumor morphological features were quantified to enhance patient risk stratification within DNA mismatch repair (MMR) groups using deep learning. Using a quantitative segmentation algorithm (QuantCRC) that identifies 15 distinct morphological features, we analyzed 402 resected stage III colon carcinomas (191 d-MMR; 189 p-MMR) from participants in a phase III trial of FOLFOX-based adjuvant chemotherapy. Results were validated in an independent cohort (176 d-MMR; 1094 p-MMR). Association of morphological features with clinicopathologic variables, MMR, KRAS, BRAFV600E, and time-to-recurrence (TTR) was determined. Multivariable Cox proportional hazard models were developed to predict TTR. Tumor morphological features differed significantly by MMR status. Cancers with p-MMR had more immature desmoplastic stroma. Tumors with d-MMR had increased inflammatory stroma, epithelial tumor-infiltrating lymphocytes (TILs), high grade histology, mucin, and signet ring cells. Stromal subtype did not differ by BRAFV600E or KRAS status. In p-MMR tumors, multivariable analysis identified tumor-stroma ratio (TSR) as the strongest feature associated with TTR [HRadj 2.02; 95% CI,1.14-3.57; P=0.018; 3-year recurrence: 40.2% vs 20.4%; Q1 vs Q2-4]. Among d-MMR tumors, extent of inflammatory stroma [continuous HRadj 0.98; 95% CI,0.96-0.99; P=0.028; 3-year recurrence: 13.3% vs 33.4%, Q4 vs Q1] and N stage were the most robust prognostically. Association of TSR with TTR was independently validated. In conclusion, QuantCRC can quantify morphological differences within MMR groups in routine tumor sections to determine their relative contributions to patient prognosis, and may elucidate relevant pathophysiologic mechanisms driving prognosis.

Improved Risk-Stratification Scheme for Mismatch-Repair Proficient Stage II Colorectal Cancers Using the Digital Pathology Biomarker QuantCRC

PURPOSE

There is a need to improve current risk stratification of stage II colorectal cancer to better inform risk of recurrence and guide adjuvant chemotherapy. We sought to examine whether integration of QuantCRC, a digital pathology biomarker utilizing hematoxylin and eosin-stained slides, provides improved risk stratification over current American Society of Clinical Oncology (ASCO) guidelines.

EXPERIMENTAL DESIGN

ASCO and QuantCRC-integrated schemes were applied to a cohort of 398 mismatch-repair proficient (MMRP) stage II colorectal cancers from three large academic medical centers. The ASCO stage II scheme was taken from recent guidelines. The QuantCRC-integrated scheme utilized pT3 versus pT4 and a QuantCRC-derived risk classification. Evaluation of recurrence-free survival (RFS) according to these risk schemes was compared using the log-rank test and HR.

RESULTS

Integration of QuantCRC provides improved risk stratification compared with the ASCO scheme for stage II MMRP colorectal cancers. The QuantCRC-integrated scheme placed more stage II tumors in the low-risk group compared with the ASCO scheme (62.5% vs. 42.2%) without compromising excellent 3-year RFS. The QuantCRC-integrated scheme provided larger HR for both intermediate-risk (2.27; 95% CI, 1.32-3.91; P = 0.003) and high-risk (3.27; 95% CI, 1.42-7.55; P = 0.006) groups compared with ASCO intermediate-risk (1.58; 95% CI, 0.87-2.87; P = 0.1) and high-risk (2.24; 95% CI, 1.09-4.62; P = 0.03) groups. The QuantCRC-integrated risk groups remained prognostic in the subgroup of patients that did not receive any adjuvant chemotherapy.

CONCLUSIONS

Incorporation of QuantCRC into risk stratification provides a powerful predictor of RFS that has potential to guide subsequent treatment and surveillance for stage II MMRP colorectal cancers.

Clinico-demographic characteristics and outcomes of radiation-induced sarcomas (RIS): a CanSaRCC study

Background

Radiation-induced sarcomas (RIS) tend to have aggressive behaviour and because of their rarity, the most appropriate management for these malignancies is uncertain.

Objectives

Using the Canadian Sarcoma Research and Clinical Collaboration (CanSaRCC) database, a national sarcoma registry, we aimed to investigate prognostic factors and outcomes for RIS.

Design

Retrospective study of RIS patients treated from 1996 to 2021 at three Canadian centres.

Methods

RIS was defined as a sarcoma arising in a previously irradiated field following a 3+ year latency period, whose histology was distinct from the initially irradiated tumour. Clinicopathologic and treatment-related information was extracted from the CanSaRCC database. Overall survival (OS) was defined as the time from RIS diagnosis to death from any cause. Response rate (RR) to neoadjuvant chemotherapy (NACT) was based on physician assessment. Time-to-event analyses were estimated using the Kaplan-Meier method, with Cox regression for multivariate analysis. We considered a two-tailed p-value of <0.05 as statistically significant.

Results

One hundred seven tumours met the criteria for RIS and were divided into three subgroups: breast angiosarcoma (BAS, n = 54), osteosarcoma (OST, n = 16), and other soft-tissue sarcomas (STS, n = 37). Patients were mostly female (n = 85, 79%), treated initially for breast carcinomas (n = 54, 50.5%), and diagnosed with high-grade tumours (n = 61/71, 86%). None had evidence of synchronous metastasis. Patients with OST were younger (median age: 48 years, p < 0.001), and BAS had the shortest latency interval (8 versus 18 years for OST/STS, p < 0.001). Most patients underwent surgery, 76% (n = 76/100) R0; 24% (n = 26) received radiation therapy, mostly (n = 15, 57.7%) neoadjuvant. Among those receiving chemotherapy, 30 (75%) underwent NACT; among patients with documented response assessment, the RR was 68% (n = 17/25), being even higher in the BAS population (89.5%, n = 13/17). Median OS was 53 months (95% CI 34-101), with a 5-year OS of 47.6%; larger tumour size, high histologic grade and older age were independent prognostic factors for worse OS.

Conclusion

Surgery is standard, and NACT might be useful to downsize large lesions, especially in BAS patients. Raising RIS awareness is fundamental to promoting appropriate management and fostering research through multi-institutional collaborations.

Prognostic Significance of Tumour Budding and Desmoplastic Reaction in Intestinal-Type Gastric Adenocarcinoma

Objective. Tumour budding and desmoplastic reactions in peritumoural stroma are features of the tumour microenvironment that are associated with colorectal cancer prognosis but have not been as thoroughly examined in gastric cancer. We aimed to further characterize the prognostic role of tumour budding and desmoplastic reaction in gastric adenocarcinoma with intestinal differentiation. Methods. 76 curative gastrectomy specimens were identified, excluding post-neoadjuvant cases or cases with >50% diffuse-type histology. Tumour budding was defined and graded according to the International Tumor Budding Consensus Conference recommendations and desmoplastic reaction was classified as described by Ueno et al 2017. Tumour budding and desmoplastic reaction were analyzed for associations with pathologic features and clinical outcomes. Results. Tumour budding was associated with pT (P < .001), pN (P < .004), overall stage (P < .001), LVI (P < .001) and PNI (P = .002). Desmoplastic reaction was associated with pT (P < .001), pN (P = .005), overall stage (P = .031) and PNI (P < .001), but not LVI. Survival analysis showed decreased overall survival (OS) and recurrence-free survival (RFS) for intermediate and high grade tumour budding (P = .031, .014 respectively). Immature stroma was significantly associated with RFS but not OS. Neither tumour budding nor desmoplastic reaction were independent predictors of OS or RFS on multivariate analysis in this cohort. Conclusion. Tumour budding and desmoplastic reaction were associated with known pathologic risk factors. Prognostically, tumour budding was associated with OS and RFS while desmoplastic reaction was associated with RFS only. Our data suggest that tumour budding and desmoplastic reaction have prognostic value in intestinal-type gastric adenocarcinoma.

Retrospective Analysis of Retroperitoneal-Abdominal-Pelvic Ganglioneuromas: An International Study by the Transatlantic Australasian Retroperitoneal Sarcoma Working Group (TARPSWG)

OBJECTIVE

The Transatlantic Australasian Retroperitoneal Sarcoma Working Group conducted a retrospective study on the disease course and clinical management of ganglioneuromas.

BACKGROUND

Ganglioneuromas are rare tumors derived from neural crest cells. Data on these tumors remain limited to case reports and single-institution case series.

METHODS

Patients of all ages with pathologically confirmed primary retroperitoneal, intra-abdominal, and pelvic ganglioneuromas between January 1, 2000, and January 1, 2020, were included. We examined demographic, clinicopathologic, and radiologic characteristics, as well as clinical management.

RESULTS

Overall, 328 patients from 29 institutions were included. The median age at diagnosis was 37 years with 59.1% of patients being female. Symptomatic presentation comprised 40.9% of cases, and tumors were often located in the extra-adrenal retroperitoneum (67.1%). At baseline, the median maximum tumor diameter was 7.2 cm. One hundred sixteen (35.4%) patients underwent active surveillance, whereas 212 (64.6%) patients underwent resection with 74.5% of operative cases achieving an R0/R1 resection. Serial tumor evaluations showed that malignant transformation to neuroblastoma was rare (0.9%, N=3). Tumors undergoing surveillance had a median follow-up of 1.9 years, with 92.2% of ganglioneuromas stable in size. With a median follow-up of 3.0 years for resected tumors, 84.4% of patients were disease free after resections, whereas recurrences were observed in 4 (1.9%) patients.

CONCLUSIONS

Most ganglioneuromas have indolent disease courses and rarely transform to neuroblastoma. Thus, active surveillance may be appropriate for benign and asymptomatic tumors particularly when the risks of surgery outweigh the benefits. For symptomatic or growing tumors, resection may be curative.

Quantitative Pathologic Analysis of Digitized Images of Colorectal Carcinoma Improves Prediction of Recurrence-Free Survival

BACKGROUND & AIMS

To examine whether quantitative pathologic analysis of digitized hematoxylin and eosin slides of colorectal carcinoma (CRC) correlates with clinicopathologic features, molecular alterations, and prognosis.

METHODS

A quantitative segmentation algorithm (QuantCRC) was applied to 6468 digitized hematoxylin and eosin slides of CRCs. Fifteen parameters were recorded from each image and tested for associations with clinicopathologic features and molecular alterations. A prognostic model was developed to predict recurrence-free survival using data from the internal cohort (n = 1928) and validated on an internal test (n = 483) and external cohort (n = 938).

RESULTS

There were significant differences in QuantCRC according to stage, histologic subtype, grade, venous/lymphatic/perineural invasion, tumor budding, CD8 immunohistochemistry, mismatch repair status, KRAS mutation, BRAF mutation, and CpG methylation. A prognostic model incorporating stage, mismatch repair, and QuantCRC resulted in a Harrell's concordance (c)-index of 0.714 (95% confidence interval [CI], 0.702-0.724) in the internal test and 0.744 (95% CI, 0.741-0.754) in the external cohort. Removing QuantCRC from the model reduced the c-index to 0.679 (95% CI, 0.673-0.694) in the external cohort. Prognostic risk groups were identified, which provided a hazard ratio of 2.24 (95% CI, 1.33-3.87, P = .004) for low vs high-risk stage III CRCs and 2.36 (95% CI, 1.07-5.20, P = .03) for low vs high-risk stage II CRCs, in the external cohort after adjusting for established risk factors. The predicted median 36-month recurrence rate for high-risk stage III CRCs was 32.7% vs 13.4% for low-risk stage III and 15.8% for high-risk stage II vs 5.4% for low-risk stage II CRCs.

CONCLUSIONS

QuantCRC provides a powerful adjunct to routine pathologic reporting of CRC. A prognostic model using QuantCRC improves prediction of recurrence-free survival.

Postnephrectomy outcomes following en bloc resection of primary retroperitoneal sarcoma: multicentre study

This article reports on postoperative renal function in the largest series of patients with primary retroperitoneal sarcoma undergoing nephrectomy at three high-volume sarcoma centres. Although half of patients develop chronic kidney disease of stage 3 or higher, rarely do patients develop acute renal failure requiring renal replacement therapy.

Survival Benefit for Individuals With Constitutional Mismatch Repair Deficiency Undergoing Surveillance

Constitutional mismatch repair deficiency syndrome (CMMRD) is a lethal cancer predisposition syndrome characterized by early-onset synchronous and metachronous multiorgan tumors. We designed a surveillance protocol for early tumor detection in these individuals.

Morbidity and Outcomes After Distal Pancreatectomy for Primary Retroperitoneal Sarcoma: An Analysis by the Trans-Atlantic Australasian Retroperitoneal Sarcoma Working Group

BACKGROUND

Multi-visceral resection often is used in the treatment of retroperitoneal sarcoma (RPS). The morbidity after distal pancreatectomy for primary pancreatic cancer is well-documented, but the outcomes after distal pancreatectomy for primary RPS are not. This study aimed to evaluate morbidity and oncologic outcomes after distal pancreatectomy for primary RPS.

METHODS

In this study, 26 sarcoma centers that are members of the Trans-Atlantic Australasian Retroperitoneal Sarcoma Working Group (TARPSWG) retrospectively identified consecutive patients who underwent distal pancreatectomy for primary RPS from 2008 to 2017. The outcomes measured were 90-day severe complications (Clavien-Dindo ≥ 3), postoperative pancreatic fistula (POPF) rate, and oncologic outcomes.

RESULTS

Between 2008 and 2017, 280 patients underwent distal pancreatectomy for primary RPS. The median tumor size was 25 cm, and the median number of organs resected, including the pancreas, was three. In 96% of the operations, R0/R1 resection was achieved. The 90-day severe complication rate was 40 %. The grades B and C POPF complication rates were respectively 19% and 5% and not associated with worse overall survival. Administration of preoperative radiation and factors to mitigate POPF did not have an impact on the risk for the development of a POPF. The RPS invaded the pancreas in 38% of the patients, and local recurrence was doubled for the patients who had a microscopic, positive pancreas margin (hazard ratio, 2.0; p = 0.042).

CONCLUSION

Distal pancreatectomy for primary RPS has acceptable morbidity and oncologic outcomes and is a reasonable approach to facilitate complete tumor resection.

Strategies for care of patients with gastrointestinal stromal tumor or soft tissue sarcoma during COVID-19 pandemic: A guide for surgical oncologists

The coronavirus disease-2019 (COVID-19) pandemic is deeply impacting the accessibility of cancer patients to surgery. In resource-limited conditions, the standard of care might not be deliverable, but evidence to support alternative management strategies often exists. By revisiting available treatment options, this review provides surgical oncologists with an evidence-based framework for treating patients with gastrointestinal stromal tumor, extremity/truncal soft tissue sarcoma, and retroperitoneal sarcoma to rapidly adapt their decision-making to the constant evolution of the COVID-19 pandemic.

Barriers and facilitators to CDH1 carriers contemplating or undergoing prophylactic total gastrectomy

Hereditary diffuse gastric cancer (HDGC) is an inherited cancer syndrome associated with high lifetime risk of diffuse-type gastric cancer. Current guidelines recommend individuals with HDGC undergo prophylactic total gastrectomy (PTG) to eliminate this risk. However, PTG is associated with significant lifestyle changes, post-surgical recovery, and symptom burden. This study examined factors related to decision-making about PTG in three groups of individuals who: (1) underwent PTG immediately after receiving genetic testing results; (2) delayed PTG by ≥ 1 year or; (3) declined PTG. Participants were recruited from a familial gastric cancer registry at a tertiary care hospital. Patients with CDH1 pathogenic or likely pathogenic variants who contemplated and/or underwent PTG were eligible. 24 individuals contemplated PTG: 9 had immediate surgery (within a year), 8 delayed surgery, and 7 declined surgery. Data on PTG barriers and facilitators were obtained on all participants using quantitative surveys (n = 7), qualitative interviews (n = 8) or both methods (n = 9). PTG barriers included age, positive beliefs about screening, close relatives with negative PTG experiences, fertility-related concerns, and life stress. Facilitators included social support, trust in healthcare providers, understanding risk, negative beliefs about screening, family-related factors, positive or abnormal screening results, and positive attitude toward PTG. This study highlights factors related to the PTG decision-making process among individuals with HDGC from three distinct groups. Future research should explore educational interventions aimed at addressing surgery-related concerns and the limitations of screening, and might also consider incorporating close relatives as informational supports.

Germline variants and phenotypic spectrum in a Canadian cohort of individuals with diffuse gastric cancer

Background

CDH1 pathogenic variants (pvs) cause most cases of inherited diffuse gastric cancer (dgc), but have low detection rates and vary geographically. In the present study, we examined hereditary causes of dgc in patients in Ontario.

Methods

CDH1 testing through single-site or multi-gene panels was conducted for patients with dgc meeting the 2015 International Gastric Cancer Linkage Consortium (igclc) criteria, or with isolated dgc at less than 50 years of age, or with a strong family history of cancer identified at the Zane Cohen Centre (zcc). All CDH1-positive patients at zcc, regardless of cancer history, were summarized.

Results

In 15 of 85 patients with dgc (17.6%), a pv or likely pv was identified through CDH1 single-site (n = 43) or multi-gene panel (n = 42) testing. The detection rate was 9.4% overall (8 of 85) and 11% using igclc criteria (7 of 65). No CDH1 pvs were identified in patients with isolated dgc at less than 40 years of age, but 1 pv was identified in a patient with isolated dgc at less than 50 years of age. Multi-gene panels identified 9 pvs (21.4%), including CDH1, STK11, ATM, BRCA2, MLH1, and MSH2. Review of 81 CDH1 carriers identified 10% with dgc (median age: 48 years; range: 38-59 years); 41% were unaffected (median age: 53 years; range: 26-89 years). Observed malignancies other than dgc or lobular breast cancer (lbc) included colorectal, gynecologic, kidney or bladder, prostate, testicular, and ductal breast cancers. Lobular-breast cancer was seen only in 3 families.

Conclusions

In Ontario, the detection rate of CDH1 pvs in patients with dgc was low: no pvs were identified in patients with isolated dgc at less than 40 years of age, and 1 was identified in a patient with isolated dgc at less than 50 years of age. Isolated lbc with no dgc was observed in CDH1-positive families, as were pathology-confirmed nondgc or non-lbc malignancies, which had not previously been reported. Given a phenotype that overlaps with other hereditary conditions, multi-gene panels are recommended for all patients with dgc at less than 50 years of age and for those meeting igclc criteria.

Intercontinental collaborative experience with abdominal, retroperitoneal and pelvic schwannomas

Background

Schwannomas are rare tumours that pose a significant management challenge in the abdomen, retroperitoneum and pelvis. No data are available to inform management strategy.

Methods

A collaborative international cohort study, across specialist sarcoma units, was conducted to include adults presenting between 2000 and 2017 with histopathologically confirmed schwannomas within the abdomen, retroperitoneum or pelvis.

Results

Of 485 patients across 12 centres, 38 (7·8 per cent) were discharged without follow-up, 199 (41·0 per cent) underwent early resection and 248 (51·1 per cent) had radiological monitoring. Of these 248 patients, 96 (38·7 per cent) eventually had surgery, giving an overall resection rate of 60·8 per cent (295 of 485). At baseline, median tumour volume was 90·1 (i.q.r. 26·5–262·0) cm3. The estimated growth rate was 10·5 (95 per cent c.i. 9·4 to 11·6) per cent per year, and was consistent in the short term (within 2 years of diagnosis) and long term (beyond 2 years) (ρ = 0·405, P = 0·021). A decision to operate was more common in symptomatic patients (P &lt; 0·001) and for rapidly growing tumours (growth rate more than 20 per cent per year) (P = 0·025). R0/R1 resection was achieved in 91·6 per cent of patients (263 of 287). Kaplan–Meier long-term recurrence rates after R0/R1 resection were 2·3 and 6·7 per cent at 3 and 5 years respectively.

Conclusion

Specific recommendations include: indications for early surgery, prediction of growth from radiological monitoring, promotion of selective submacroscopic resection and cessation of postoperative imaging surveillance.

Outcomes by treatment modality in elderly patients with localized gastric and esophageal cancer

Background

We aimed to assess current treatment patterns and outcomes in elderly patients with localized gastric and esophageal (ge) cancers.

Methods

This retrospective analysis considered patients 75 years of age or older with ge cancers treated during 2012-2014. Patient demographics and tumour characteristics were collected. Overall survival (os) and disease-free survival were assessed by univariable and multivariable Cox proportional hazards regression, adjusting for demographics. Logistic regression analyses were used to examine factors affecting treatment choices.

Results

The 110 patients in the study cohort had a median age of 81 years (range: 75-99 years). Primary disease sites were esophageal (55%) and gastric (45%). Treatment received included radiation therapy alone (29%), surgery alone (26%), surgery plus perioperative therapy (14%), chemoradiation alone (10%), and supportive care alone (14%). In multivariable analyses, surgery (hazard ratio: 0.48; 95% confidence interval: 0.26 to 0.90; p = 0.02) was the only independent predictor for improved os. Patients with a good Eastern Cooperative Oncology Group performance status (p = 0.008), gastric disease site (p = 0.02), and adenocarcinoma histology (p = 0.01) were more likely to undergo surgery.

Conclusions

At our institution, few patients 75 years of age and older received multimodality therapy for localized ge cancers. Outcomes were better for patients who underwent surgery than for those who did not. To ensure optimal treatment selection, comprehensive geriatric assessment should be considered for patients 75 years of age and older with localized ge cancers.

TOPGEAR: A Randomized, Phase III Trial of Perioperative ECF Chemotherapy with or Without Preoperative Chemoradiation for Resectable Gastric Cancer: Interim Results from an International, Intergroup Trial of the AGITG, TROG, EORTC and CCTG

BACKGROUND

Postoperative chemoradiation and perioperative chemotherapy using epirubicin/cisplatin/5-fluorouracil (ECF) represent two standards of care for resectable gastric cancer. In the TOPGEAR (Trial Of Preoperative therapy for Gastric and Esophagogastric junction AdenocaRcinoma) trial, we hypothesized that adding preoperative chemoradiation to perioperative ECF will improve survival; however, the safety and feasibility of preoperative chemoradiation have yet to be determined.

METHODS

TOPGEAR is an international phase III trial in which patients with adenocarcinoma of the stomach were randomized to perioperative ECF alone or with preoperative chemoradiation. The ECF-alone group received three preoperative cycles of ECF, while the chemoradiation group received two cycles of preoperative ECF followed by chemoradiation. Both groups received three postoperative cycles of ECF. A planned interim analysis of the first 120 patients was conducted, and was reviewed by the Independent Data Safety Monitoring Committee to assess treatment compliance, toxicity/safety, and response rates.

RESULTS

The proportion of patients who received all cycles of preoperative chemotherapy was 93% (ECF group) and 98% (chemoradiation group), while 65 and 53%, respectively, received all cycles of postoperative chemotherapy. Overall, 92% of patients allocated to preoperative chemoradiation received this treatment. The proportion of patients proceeding to surgery was 90% (ECF group) and 85% (chemoradiation group). Grade 3 or higher surgical complications occurred in 22% of patients in both groups. Furthermore, grade 3 or higher gastrointestinal toxicity occurred in 32% (ECF group) and 30% (chemoradiation group) of patients, while hematologic toxicity occurred in 50 and 52% of patients.

CONCLUSIONS

These results demonstrate that preoperative chemoradiation can be safely delivered to the vast majority of patients without a significant increase in treatment toxicity or surgical morbidity.

Phase 1/2 Study of the Addition of Cisplatin to Adjuvant Chemotherapy With Image Guided High-Precision Radiation Therapy for Completely Resected Gastric Cancer

PURPOSE

Locoregional recurrence is common after surgery for gastric cancer. Adjuvant therapy improves outcomes but with toxicity. This phase 1/2 study investigated infusional 5-fluorouracil (5-FU) in combination with biweekly cisplatin delivered concurrently with image guided high-precision radiation therapy.

METHODS AND MATERIALS

Eligible patients had completely resected stage IB to IV (Union for International Cancer Control TNM 6th edition) nonmetastatic gastric adenocarcinoma. Treatment constituted 12 weeks of infusional 5-FU (200 mg/m²/day) with cisplatin added in a standard 3 + 3 dose escalation protocol (0, 20, 30, and 40 mg/m²) during weeks 1, 3, 5, and 7, and an additional week 9 dose in the final cohort. Radiation therapy (45 Gy in 25 fractions) was delivered during weeks 3 to 7. Maximum tolerated dose (MTD) was determined in phase 1 and confirmed in phase 2.

RESULTS

Among the 55 patients (median age, 54 years; range 28-77 years; 55% male), the median follow-up time was 3.0 years (range, 0.3-5.3 years). Five patients in phase 1 experienced dose-limiting toxicity, and MTD was determined as 4 cycles of 40 mg/m² cisplatin. Twenty-seven patients were treated at MTD. Acute grade 3 to 4 toxicity rate was 37.0% at MTD and 29.1% across all dose levels. No treatment-related deaths occurred. Fourteen patients experienced recurrent disease. The 2-year overall survival (OS) and relapse-free survival were 85% and 74%, respectively. Median OS has not been reached. Quality of life (QOL) was impaired during treatment, but most scores recovered by 4 weeks.

CONCLUSION

Cisplatin can be safely delivered with 5-FU-based chemoradiation therapy. Acute toxicity was acceptable, and patient-reported QOL showed the regimen was tolerable. Outcomes are encouraging and justify further study of this regimen.

TOPGEAR: a randomised phase III trial of perioperative ECF chemotherapy versus preoperative chemoradiation plus perioperative ECF chemotherapy for resectable gastric cancer (an international, intergroup trial of the AGITG/TROG/EORTC/NCIC CTG)

BACKGROUND

The optimal management of patients with resectable gastric cancer continues to evolve in Western countries. Following publication of the US Intergroup 0116 and UK Medical Research Council MAGIC trials, there are now two standards of care for adjuvant therapy in resectable gastric cancer, at least in the Western world: postoperative chemoradiotherapy and perioperative epirubicin/cisplatin/fluorouracil (ECF) chemotherapy. We hypothesize that adding chemoradiation to standard perioperative ECF chemotherapy will achieve further survival gains. We also believe there are advantages to administering chemoradiation in the preoperative rather than postoperative setting. In this article, we describe the TOPGEAR trial, which is a randomised phase III trial comparing control arm therapy of perioperative ECF chemotherapy with experimental arm therapy of preoperative chemoradiation plus perioperative ECF chemotherapy.

METHODS/DESIGN

Eligible patients with resectable adenocarcinoma of the stomach or gastroesophageal junction will be randomized to receive either perioperative chemotherapy alone (3 preoperative and 3 postoperative cycles of ECF) or perioperative chemotherapy plus preoperative chemoradiation. In the chemoradiation arm, patients receive 2 cycles of ECF plus chemoradiation prior to surgery, and then following surgery 3 further cycles of ECF are given. The trial is being conducted in two Parts; Part 1 (phase II component) has recruited 120 patients with the aim of assessing feasibility, safety and preliminary efficacy of preoperative chemoradiation. Part 2 (phase III component) will recruit a further 632 patients to provide a total sample size of 752 patients. The primary endpoint of the phase III trial is overall survival. The trial includes quality of life and biological substudies, as well as a health economic evaluation. In addition, the trial incorporates a rigorous quality assurance program that includes real time central review of radiotherapy plans and central review of surgical technique.

DISCUSSION

TOPGEAR is an international, intergroup collaboration led by the Australasian Gastro-Intestinal Trials Group (AGITG), in collaboration with the Trans-Tasman Radiation Oncology Group (TROG), European Organisation for Research and Treatment of Cancer (EORTC) and the NCIC Clinical Trials Group. It addresses a globally significant question that will help inform future international standards for clinical practice in resectable gastric cancer.

TRIAL REGISTRATION

Australian New Zealand Clinical Trials Registry: ACTRN12609000035224 . Registered 30 May 2009.

Pregnancy and maternal outcomes in women with prior or current gastrointestinal malignancies

OBJECTIVES

To review the fetal and maternal outcomes of women with a diagnosis of gastrointestinal (GI) cancer before or during pregnancy.

METHODS

We conducted a retrospective cohort study of pregnant women referred to a single tertiary care centre with a current or previous diagnosis of GI malignancy. Maternal, obstetric, and infant data were recorded.

RESULTS

We identified 18 pregnancies in 13 women. Nine women were found to have a GI malignancy during pregnancy (group 1). There was an indirect maternal death in this group in a woman with advanced gastric adenocarcinoma. Nine unique pregnancies occurred in eight women with diagnosis and management of GI malignancies before their pregnancies (group 2).

CONCLUSION

GI malignancies are difficult to diagnose and manage during pregnancy and are usually advanced at the time of diagnosis. Surgery can be performed during pregnancy if necessary, with chemotherapy and radiotherapy usually deferred to the postpartum period. Women who have had a prior GI malignancy have special circumstances related to the type of surgery performed and previous exposure to chemotherapy. These patients may benefit from a multidisciplinary team effort to optimize their care.

Processes of care in the multidisciplinary treatment of gastric cancer: results of a RAND/UCLA expert panel

IMPORTANCE

There is growing interest in reducing the variations and deficiencies in the multidisciplinary management of gastric cancer.

OBJECTIVE

To define optimal treatment strategies for gastric adenocarcinoma (GC).

DESIGN, SETTING, AND PARTICIPANTS

RAND/UCLA Appropriateness Method involving a multidisciplinary expert panel of 16 physicians from 6 countries.

INTERVENTIONS

Gastrectomy, perioperative chemotherapy, adjuvant chemoradiation, surveillance endoscopy, and best supportive care.

MAIN OUTCOMES AND MEASURES

Panelists scored 416 scenarios regarding treatment scenarios for appropriateness from 1 (highly inappropriate) to 9 (highly appropriate). Median appropriateness scores from 1 to 3 were considered inappropriate; 4 to 6, uncertain; and 7 to 9, appropriate. Agreement was reached when 12 of 16 panelists scored the scenario similarly. Appropriate scenarios agreed on were subsequently scored for necessity.

RESULTS

For patients with T1N0 disease, surgery alone was considered appropriate, while there was no agreement over surgery alone for patients T2N0 disease. Perioperative chemotherapy was appropriate for patients who had T1-2N2-3 or T3-4 GC without major symptoms. Adjuvant chemoradiotherapy was classified as appropriate for T1-2N1-3 or T3-4 proximal GC and necessary for T1-2N2-3 or T3-4 distal GC. There was no agreement regarding surveillance imaging and endoscopy following gastrectomy. Surveillance endoscopy was deemed to be appropriate after endoscopic resection. For patients with metastatic GC, surgical resection was considered inappropriate for those with no major symptoms, unless the disease was limited to positive cytology alone, in which case there was disagreement.

CONCLUSIONS AND RELEVANCE

Patients with GC being treated with curative intent should be considered for multimodal treatment. For patients with incurable disease, surgical interventions should be considered only for the management of major bleeding or obstruction.

What provider volumes and characteristics are appropriate for gastric cancer resection? Results of an international RAND/UCLA expert panel

BACKGROUND

A relationship between higher volume providers and improved outcomes has been suggested by some studies and has been used to construct guidelines for many diseases. For gastric cancer (GC), however, optimal volume cutoffs are not clear.

METHODS

A multidisciplinary expert panel of 16 physicians from 6 countries scored 120 scenarios regarding provider characteristics for gastric resections for GC. Appropriateness of scenarios was scored from 1 (highly inappropriate) to 9 (highly appropriate). Median appropriateness scores from 1 to 3 were considered inappropriate, 4 to 6 uncertain, and 7 to 9 appropriate. Agreement was reached when 12 of 16 panelists scored the statement similarly. Appropriate scenarios agreed on were scored subsequently for necessity.

RESULTS

Surgeon and hospital practice volume scenarios were evaluated. The panel felt it was inappropriate for surgeons doing ≤2 GC cases per year to perform a multivisceral resection (MVR), D2 lymphadenectomy (D2-LND), or laparoscopic total gastrectomy, and ≤6 GC cases per year for an MVR involving a pancreatoduodenectomy (MVR-PD), or endoscopic mucosal resections (EMR). It was considered appropriate for surgeons doing ≥11 GC cases per year to perform open gastrectomy or D2-LND, and ≥20 GC cases per year for any MVR, laparoscopic gastrectomy, or EMR. For hospitals, it was considered inappropriate for hospitals managing ≤4 GC cases per year to perform D2-LND or laparoscopic total gastrectomy, and ≤10 GC cases per year, for MVR-PD or EMR. Hospital volumes ≥21 cases per year was considered appropriate for any GC procedure. It was inappropriate for an MVR to be performed in a hospital without interventional radiology services and for a MVR-PD in a hospital with no level I intensive care unit.

CONCLUSION

Appropriate and inappropriate provider volumes for a variety of gastric procedures have been defined by an international expert panel.

Abstract 1362: Developing genetically flexible mouse models of sarcoma - a novel functional genomics platform

Introduction: Sarcomas are a heterogeneous group of malignant neoplasms that arise from connective tissues and have a disease-specific mortality of 30-50%. Existing mouse models of sarcomagenesis utilize knockout and transgenic mice but it is unclear if fixed germline mutations recapitulate sporadic human cancer. In addition, creating germline mutant mice requires substantial time and resources. We hypothesized that delivery of oncogenes into mouse skeletal muscle using a retroviral (RCAS) system would result in sarcomagenesis and could mitigate the limitations of conventional mouse models. Methods: p16/p19 null mice expressing the retroviral receptor, TVA, under nestin (N-tva) or β-actin (BKE) promoters were used. DF1 chicken fibroblasts, infected with avian-leukosis virus vectors (RCAS) carrying combinations of oncogenes (KrasG12D, c-Myc, IGF2) or GFP alone, were delivered by injection into the hindlegs of neonatal mice and tumor development was monitored. Results: GFP-positive cells were observed following in vitro infection of cultured mouse skeletal muscle with RCAS-GFP and GFP+ myoblasts were identified from mice injected with RCAS-GFP in vivo, suggesting successful cell infection and targeted gene delivery. Sarcomas formed in 30% of p16/p19−/−xN-tva mice at the injection site with a median latency of 23.5 weeks (8-42 weeks). Several subtypes of sarcoma developed in this strain based on morphologic assessment and immunohistochemistry (S100, desmin, and smooth muscle actin). Of these, malignant peripheral nerve sheath tumor (MPNST) that overexpressed EGFR consistent with human MPNST, was the predominant subtype (55%). Although a similar tumor incidence occurred in the p16/p19−/−xBKE strain (32%), the median latency was much shorter, 10.4 weeks (7-25 weeks) and the tumor spectrum shifted to predominantly fibrosarcoma (36%) or rhabdomyosarcoma (36%). No tumors were observed in mice injected with empty RCAS vector or without inactivation of the p16/p19 locus. Gene-anchored PCR revealed retroviral vector DNA integration in 89% of N-tva and 97% of BKE tumors. KrasG12D was the most frequent oncogene isolated. Conclusions: We have generated novel models of sarcomagenesis using the RCAS-TVA system to deliver known sarcoma oncogenes into mouse hind legs with a tumor incidence of ∼30%. With optimization, we will be able to use this genetically flexible system to functionally validate novel candidate sarcoma genes.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 1362. doi:1538-7445.AM2012-1362

Adjuvant chemoradiation for gastric cancer with infusional 5-fluorouracil and cisplatin: a phase I study

OBJECTIVE

This phase I study aimed to determine the maximal tolerated dose of cisplatin administered every 2 weeks with infusional 5-fluorouracil (5FU) and concurrent radiation therapy (RT) in patients after complete resection of gastric adenocarcinoma.

METHODS

Patients with resected stage IB to IV (M0) gastric adenocarcinoma were treated with 12 weeks of infusional 5FU (200 mg/m(2) daily) and with RT (45 Gy in 25 fractions starting on day 16). Cisplatin was administered in escalating doses (0, 20, 30, and 40 mg/m(2)) in weeks 1, 3, 5, and 7. In the final cohort, patients received an additional dose of cisplatin (40 mg/m(2)) in week 9.

RESULTS

Among the 34 patients [median age: 56 years (range: 31-77 years)] who were assessable for toxicity, 5 experienced dose-limiting toxicities: 1 sepsis (cohort 1), 1 fatigue (cohort 2), 3 upper gastrointestinal toxicity (1 in cohort 2, 2 in cohort 5). Cohort 5 exceeded the maximal tolerated dose. Median follow-up was 2.5 years (range: 0.3-5 years). The 3-year overall and relapse-free survival rates were 86% and 71% respectively; median survival was not reached.

CONCLUSIONS

Cisplatin was well tolerated in combination with infusional 5FU and RT, showing promising activity in the adjuvant treatment of gastric cancer. Infusional 5FU 200 mg/m(2) daily for 12 weeks with cisplatin 40 mg/m(2) in weeks 1, 3, 5, and 7 and with concurrent RT 45 Gy in 25 fractions, starting at day 16, is being explored in a phase II study at our institution.

In situ hypothermic liver preservation during radical liver resection with major vascular reconstruction

BACKGROUND

The in situ hypothermic liver preservation technique may allow a more aggressive approach to tumours of the caval confluence and/or all three hepatic veins, which would otherwise be deemed irresectable.

METHODS

All descriptive data regarding patient demographics, operative characteristics, perioperative complications and outcomes of nine patients in whom this technique was used were collected prospectively.

RESULTS

Seven patients underwent liver trisegmentectomy and two had primary retrohepatic venal caval resection. Total hepatic vascular occlusion with in situ hypothermic liver preservation was used for venous reconstruction in all patients. The vena cava was reconstructed with prosthetic graft in seven patients. All main hepatic veins were reconstructed in the seven liver resections. In situ hypothermic liver preservation was well tolerated as evidenced by preserved hepatic synthetic function early after operation. One patient died 66 days after surgery. There were two recurrences after a median follow-up of 14 (range 2-33) months; local recurrence was identified in one patient after 4 months and distant metastasis in another after 8 months.

CONCLUSION

The in situ hypothermic liver preservation technique appears to be a useful adjunct to radical hepatobiliary tumour excision procedures that require total hepatic vascular exclusion and major vascular reconstruction.