Gastric Cancer Etiology and Management in Asia and the West.

Regional variation in treatment paradigms for gastric adenocarcinoma has attracted a great deal of interest. Between Asia and the West, major differences have been identified in tumor biology, implementation of screening programs, extent of surgical lymphadenectomy, and routine use of neoadjuvant versus adjuvant treatment strategies. Minimally invasive techniques, including both laparoscopic and robotic platforms, have been studied in both regions, with attention to safety, feasibility, and long-term oncologic outcomes. The purpose of this review is to discuss advances in the understanding of the etiology and underlying biology of gastric cancer, as well as the current state of management, focusing on the differences between Asia and the West.

Robotic Gastrectomy for Gastric Adenocarcinoma in the USA: Insights and Oncologic Outcomes in 220 Patients.

BACKGROUND: While multiple Asian and a few Western retrospective series have demonstrated the feasibility and safety of robotic-assisted gastrectomy for gastric cancer, its reliability for thorough resection, especially for locoregional disease, has not yet been firmly established, and reported learning curves vary widely. To support wider implementation of robotic gastrectomy, we evaluated the learning curve for this approach, assessed its oncologic feasibility, and created a selection model predicting the likelihood of conversion to open surgery in a US patient population. PATIENTS AND METHODS: We retrospectively reviewed data on all consecutive patients who underwent robotic gastrectomy at a high-volume institution between May 2012 and March 2019. RESULTS: Of the 220 patients with gastric cancer selected to undergo curative-intent robotic gastrectomy, surgery was completed using robotics in 159 (72.3%). The median number of removed lymph nodes was 28, and ≥ 15 lymph nodes were removed in 94% of procedures. Surgical time decreased steadily over the first 60-80 cases. Complications were generally minor: 7% of patients experienced complications of grade 3 or higher, with an anastomotic leak rate of 2% and mortality rate 0.9%. Factors predicting conversion to open surgery included neoadjuvant chemotherapy, BMI ≥ 31 kg/m2, and tumor size ≥ 6 cm. CONCLUSIONS: These findings support the safety and oncologic feasibility of robotic gastrectomy for selected patients with gastric cancer. Proficiency can be achieved by 20 cases and mastery by 60-80 cases. Ideal candidates for this approach are patients with few comorbidities, BMI < 31 kg/m2, and tumors < 6 cm.

Predicting malignancy in patients with adrenal tumors using 18 F-FDG-PET/CT SUVmax.

BACKGROUND AND OBJECTIVES: 18 F-fluorodeoxyglucose positron emission tomography/computed tomography (18 F-FDG-PET/CT) parameters may help distinguish malignant from benign adrenal tumors, but few have been externally validated or determined based on definitive pathological confirmation. We determined and validated a threshold for 18 F-FDG-PET/CT maximum standard uptake value (SUVmax) in patients who underwent adrenalectomy for a nonfunctional tumor. METHODS: Database review identified patients with 18 F-FDG-PET/CT images available (training cohort), or only SUVmax values (validation cohort). Discriminative accuracy was assessed by area under the curve (AUC), and the optimal cutoff value estimated by maximally selected Wilcoxon rank statistics. RESULTS: Of identified patients (n = 171), 86 had adrenal metastases, 20 adrenal cortical carcinoma, and 27 adrenal cortical adenoma. In the training cohort (n = 96), SUVmax was significantly higher in malignant versus benign tumors (median 8.3 vs. 3.0, p < .001), with an AUC of 0.857. Tumor size did not differ. The optimal cutoff SUVmax was 4.6 (p < .01). In the validation cohort (n = 75), this cutoff had a sensitivity of 75% and specificity 55%. CONCLUSIONS: 18 F-FDG-PET/CT SUVmax was associated with malignancy. Validation indicated that SUVmax ≥ 4.6 was suggestive of malignancy, while lower values did not reliably predict benign tumor.

Cancer surveillance imaging: Does repeated iodinated contrast exposure impact long-term kidney function?

BACKGROUND: Contrast-induced nephropathy is a well-recognized acute complication in cancer patients, but the long-term effects of repeated contrast exposure are not known. We analyzed the association of the number of contrast-enhanced computed tomography (CECT) examinations and other clinical factors with decline in estimated glomerular filtration rate (eGFR) in colorectal cancer survivors. MATERIALS AND METHODS: We retrospectively queried a prospective surgical colorectal cancer database to identify patients with stage I or II cancer who underwent resection in 2007 - 2013 and were alive for at least 3 years. eGFR was calculated before and 3 years after the surgery with ≥ 20% decline relative to baseline defined as significant and used as the primary outcome. The association of clinical factors with the primary outcome was analyzed using logistic regression. RESULTS: Only 256 patients with the median follow-up of 65 months had sufficient clinical data for analysis. Median eGFR decline at follow-up was 3.0 mL/min/1.73m2 or 4% change from baseline. 47 patients (18%) had ≥ 20% reduction in eGFR, which was not associated with the number of CECT examinations. Multivariable analysis demonstrated that increasing age (OR, 1.03; 95% CI, 1.00 - 1.06), presence of diabetes (OR, 2.33; 95% CI, 1.18 - 4.61), and longer operation time (OR, 1.04; 95% CI, 1.01 - 1.07) were independently associated with a higher likelihood of ≥ 20% eGFR decline at 3 years. CONCLUSION: Older age, diabetes, and longer operating time, but not cumulative contrast exposure were found to be associated with worse long-term renal outcomes following surgical resection in patients with early-stage colorectal cancer who survived 3 years.

Adrenal Metastasectomy in the Presence and Absence of Extraadrenal Metastatic Disease.

OBJECTIVE: To determine if there are differences in overall survival (OS) or event-free survival (EFS) in patients with and without concomitant extra-adrenal metastases undergoing adrenal metastasectomy. BACKGROUND: There is growing interest in the use of local therapies in patients with oligometastatic disease. Previously published series have indicated that long-term survival is possible with resection. Adrenalectomy has been used to treat adrenal metastases in select patients. METHODS: Patients who underwent adrenal metastasectomy from 1994 to 2015 were identified from a prospectively maintained institutional database of adrenalectomy patients, excluding adrenalectomies due to tumor extension or for palliation. Sites of disease, treatment history, and survival data were extracted from chart review. RESULTS: One hundred seventy-four patients were included. Tumor histology included 68 nonsmall cell lung cancer, 34 renal cancer, 18 colorectal cancer, 11 melanoma cancer, 10 hepatocellular cancer, 8 sarcoma cancer, and 25 other cancers. The median follow-up among survivors was 5.2 (1-21) years. OS at 3 and 5 years was 50% and 40%, respectively. Patients with (n = 83) and without (n = 91) extra-adrenal metastases did not differ with respect to age, adrenal tumor size, or margin status. Median OS (3.3 years for patients with concomitant extra-adrenal metastases and 3.0 years for patients with isolated adrenal metastases; P = 0.816) and EFS (9.39 vs 9.59 months; P = 0.87) were similar. Factors negatively associated with OS included adrenal tumor size (P < 0.01), renal primary versus other (P < 0.01), and adrenal margin status (P < 0.01). CONCLUSIONS: In selected patients undergoing adrenal metastasectomy, there were no significant differences in OS or EFS between patients with and without concomitant extra-adrenal metastases.

Performance of the American College of Surgeons NSQIP Surgical Risk Calculator for Total Gastrectomy.

BACKGROUND: To encourage implementation of the American College of Surgeons (ACS) NSQIP Risk Calculator for total gastrectomy for gastric cancer, its predictive performance for this specific procedure should be validated. We assessed its discriminatory accuracy and goodness of fit for predicting 12 adverse outcomes. STUDY DESIGN: Data were collected on all patients with gastric cancer who underwent total gastrectomy with curative intent at Memorial Sloan Kettering Cancer Center between 2002 and 2017. Preoperative risk factors from the electronic medical record were manually inserted into the ACS-NSQIP Risk Calculator. Predictions for adverse outcomes were compared with observed outcomes by Brier scores, c-statistics, and Hosmer-Lemeshow p value. RESULTS: In a total of 452 patients, the predicted rate of all complications (29%) was lower than the observed rate (45%). Brier scores varied between 0.017 for death and 0.272 for any complication. C-statistics were moderate (0.7-0.8) for death and renal failure, good (0.8-0.9) for cardiac complication, and excellent (≥0.9) for discharge to nursing or rehabilitation facility. Hosmer-Lemeshow p value found poor goodness of fit for pneumonia only. CONCLUSIONS: For adverse outcomes after total gastrectomy with curative intent in gastric cancer patients, performance of the ACS-NSQIP Risk Calculator is variable. Its predictive performance is best for cardiac complications, renal failure, death, and discharge to nursing or rehabilitation facility.