Prognostic significance of computed tomography defined ascites in advanced gastric cancer

An ascites grading system for predicting the prognosis of gastric cancer with peritoneum dissemination

AIM

Gastric cancer with peritoneum dissemination is intractable with surgical resection. The evaluation of the degree of dissemination using computed tomography (CT) is difficult. We focused on the amount of ascites based on CT findings and established a scaling system to predict these patients' prognoses.

METHODS

We extracted individual data from a population-based cohort. Patients diagnosed with histologically proven gastric adenocarcinoma with peritoneum dissemination were enrolled. Two raters evaluated the CT images and determined the grade of ascites in each patient: grade 0 indicated no ascites in all slices; grade 1 indicated ascites detected only in the upper or lower abdominal cavity; grade 2 indicated ascites detected in both the upper and lower abdominal cavities; and grade 3 indicated ascites extending continuously from the pelvic cavity to the upper abdominal cavity. We evaluated the relationship between the ascites grade and survival time. After adjusting for other clinical factors, we calculated hazard ratios of each ascites grade.

RESULTS

A total of 718 patients were enrolled. The number of patients with grades 0, 1, 2, and 3 were 303, 223, 94, and 98, respectively. The median overall survival times were 16.0, 8.7, 5.4, and 3.0 months for ascites on CT grades 0, 1, 2, and 3, respectively (P < .001). The adjusted hazard ratios for the survival time were 1.74 (1.33-2.26, P < .001), 3.20 (2.25-4.57, P < .001), and 4.76 (3.16-7.17, P < .001) for grades 1, 2, and 3, respectively.

CONCLUSION

We established a new grading system of pretreatment ascites to better predict the prognosis of gastric cancer.

T and N Staging of Gastric Cancer Using Dual-Source Computed Tomography

Aim

This study is aimed at comparing gastric cancer T and N staging between virtual monochromatic energy images and fusion images generated by dual-source computed tomography (DSCT) dual-energy mode data acquisition prospectively while measuring the iodine concentration of gastric cancer and lymph nodes at different T and N stages from iodine map retrospectively.

Methods

A total of 71 patients (50 males and 21 females; mean age: 59 ± 11 years) confirmed with gastric cancer by endoscopic biopsy with no neoadjuvant chemotherapy were enrolled for the CT examination before surgeries. The preoperative T and N staging results were compared between groups with pathological results as the gold standard. The iodine concentrations of the gastric lesions and LNs were measured on the iodine-based material decomposition images. All iodine concentration values were normalized against those in the abdominal aorta and defined as normalized iodine concentration (nIC) values. The short axis length of LNs and nIC values were statistically analyzed.

Results

Group A was better than group B for T3 and T4 staging. No statistically significant difference in the overall accuracies for N staging was found between groups. For the late arterial and delayed phases, T3 and T4 nIC values of the extraserosal adipose tissue showed statistically significant differences. The nIC values between N0 and Nm (N1-N3) showed statistically significant differences in the portal phase only.

Conclusions

T3 and T4 nIC values of the extraserosal adipose tissue showed statistically significant differences. Hence, dual-source CT may be helpful in the differential diagnosis between T3 and T4.

The Combination of Seven Preoperative Markers for Predicting Patients with Gastric Cancer to Be Either Stage IV or Non-Stage IV

To assess whether preoperative markers could predict the stage of patients with gastric cancer. We analyzed retrospectively the preoperative indicators between stage IV and non-stage IV gastric cancer at the Gastrointestinal Surgery of Nanjing Drum Tower Hospital. A total of 500 patients with gastric cancer were screened. Of all the variables, alpha-fetoprotein (AFP), carcinoembryonic antigen (CEA), carbohydrate antigen (CA) 125, carbohydrate antigen (CA) 199, carbohydrate antigen (CA) 724, carbohydrate antigen (CA) 242, thrombin time (TT), prothrombin time (PT), activated partial thromboplastin time (APTT), blood platelet count (PLT), white blood cell (WBC) count, C-reactive protein (CRP), neutrophil count (NC), lymphocyte count (LC), neutrophil-lymphocyte ratio (NLR), hemoglobin (HB), aspartate aminotransferase (AST), and ascites were found to have statistical differences between the two groups. Then, Stepwise Discriminant Analysis was conducted to establish a prediction model including 7 indexes (CA724, CA242, TT, PLT, CRP, AST, and ascites). According to the model, 90.6% of original grouped cases were correctly classified and 90.6% of cross-validated grouped cases were correctly classified. We built a discriminant including CA724, CA242, TT, PLT, CRP, AST, and ascites for predicting patients with gastric cancer to be either stage IV or non-stage IV. According to this discriminant, 90.6% of patients could be correctly predicted.

Clinical significance of computed tomography-detected ascites in gastric cancer patients with peritoneal metastases

Patients with peritoneal metastases (PM) are generally considered incurable; therefore, the presence of PM is a critical factor in deciding between palliative surgery and curative resection as a therapeutic strategy. Previous studies have not determined the predictive value of ascites detected on computed tomography (CT) for the presence of PM. We aimed to analyze the factors that are associated with PM in patients with CT-detected ascites.A total of 2207 consecutive patients who were diagnosed with gastric cancer between 2004 and 2013 were identified. Eleven patients with liver cirrhosis or chronic renal insufficiency with ascites and 57 patients who received previous treatment were excluded. Ninety-eight patients who had definite evidence of distant metastasis or PM on CT and 64 patients who did not undergo surgery were excluded. A total of 91 patients were enrolled in the study to analyze the association between CT-detected ascites and surgically confirmed PM.Seventy-six patients underwent curative resection and 15 patients underwent palliative surgery. Twelve patients exhibited peritoneal seeding and 37 patients showed regional lymph node metastasis. Regional lymph node metastasis, advanced gastric cancer, undifferentiated pathology, and the amount of ascites were significantly associated with PM. Multivariable logistic regression analysis identified the amount of ascites to be an independent risk factor for the presence of PM.Regional lymph node metastasis, advanced gastric cancer, undifferentiated pathology, and the amount of ascites were associated with PM. The amount of ascites was found to be an independent risk factor for PM.

Computed tomographic characteristics for patients with unresectable gastric cancer harboring low-volume peritoneal carcinomatosis

Although current staging workups could differentiate most patients with operable from inoperable advanced gastric cancers, there are still some patients with low-volume peritoneal carcinomatosis, defined as only metastasis with multiple subcentimeter lesions in peritoneum, receiving unnecessary open-close procedures. The computed tomography (CT) of the patients with unresectable advanced gastric cancer harboring low-volume peritoneal carcinomatosis was retrospectively identified and then thoroughly reviewed by two independent radiologists unaware of the peritoneal carcinomatosis status. Of the 798 patients with newly diagnosed gastric cancer between January 2007 and December 2010, 52 patients harboring advanced gastric cancer with low-volume peritoneal carcinomatosis receiving surgery with curative intent were identified. Descriptive statistic was used for the radiologic characteristics. The most common radiologic characteristic of CT was omental fat stranding (57.7%), followed by omental clustered subcentimeter nodules (53.8%), distant enlarged lymph node (40.4%), distant grouping of small lymph nodes (36.5%), peritoneal nodules or thickening (34.6%), minimal loculated ascites (21.2%), intestinal wall thickening or irregularity (9.6%), and hydronephrosis or hydroureter without stone or urothelial lesion (5.8%). Comprehensively reviewing the radiologic characteristics of CT may identify the patients harboring advanced gastric cancer with low-volume peritoneal carcinomatosis.

Evaluation and treatment of malignant ascites secondary to gastric cancer

Malignant ascites affects approximately 10% of patients with gastric cancer (GC), and poses significant difficulties for both patients and clinicians. In addition to the dismal general condition of affected patients and the diversity of associated complications such as jaundice and ileus, problems in assessing scattered tumors have hampered the expansion of clinical trials for this condition. However, the accumulation of reported studies is starting to indicate that the weak response to treatment in GC patients with malignant ascites is more relevant to their poor prognosis rather than to the ascites volume at diagnosis. Therefore, precise assessment of initial state of ascites, repetitive evaluation of treatment efficacy, selection of suitable treatment, and swift transition to other treatment options as needed are paramount to maximizing patient benefit. Accurately determining ascites volume is the crucial first step in clinically treating a patient with malignant ascites. Ultrasonography is commonly used to identify the existence of ascites, and several methods have been proposed to estimate ascites volume. Reportedly, the sum of the depth of ascites at five points (named “five-point method”) on three panels of computed tomography images is well correlated to the actual ascites volume and/or abdominal girth. This method is already suited to repetitive assessment due to its convenience compared to the conventional volume rendering method. Meanwhile, a new concept, “Clinical Benefit Response in GC (CBR-GC)”, was recently introduced to measure the efficacy of chemotherapy for malignant ascites of GC. CBR-GC is a simple and reliable patient-oriented evaluation system based on changes in performance status and ascites, and is expected to become an important clinical endpoint in future clinical trials. The principal of treatment for GC patients with ascites is palliation and prevention of ascites-related symptoms. The treatment options are various, including a standard treatment based on the available guidelines, cytoreductive surgery with hyperthermic intraperitoneal chemotherapy (HIPEC), laparoscopic HIPEC alone, intravenous chemotherapy, intraperitoneal chemotherapy, and molecular targeting therapy. Although each treatment option is valid, further research is imperative to establish the optimal choice for each patient.