Introduction: Malignant ascites accounts for approximately 10% of all cases of ascites. The presence of malignant ascites is a grave prognostic sign. Survival in this patient population is poor, averaging about 20 wk from time of diagnosis. Malignant Ascites is a common complication of advanced malignancy, but little is known regarding its prevalence and overall burden on a population level.
Methods: We conducted a retrospective analysis of Malignant Ascites associated hospitalizations using the Healthcare Cost and Utilization Project-Nationwide Inpatient Sample, Agency for Healthcare Research and Quality (HCUP-NIS 2002-2014). Cases were included if Malignant Ascites (ICD-9 Code 789.51) was coded as a primary or secondary diagnosis. All analyses were performed with the use of PROC SURVEYMEANS, SURVEYFREQUENCY and SURVEYLOGISTIC procedures of SAS, version 9.4 (SAS Institute).
Results: A sample of 189091 admissions for malignant Ascites was identified. Of these admissions, 126385 (66.8%) were for female patients. Most of the patients were Caucasians (68.9%) and of age above 65 (47.2%). Most of the patients were admitted non-electively (83.9%) to urban teaching hospitals (59.5%). Ovarian (21%), Unknown Primary (12.2%), Breast (10.1%), Pancreas (9.9%) and colon cancer (8%) were the most common five primary malignancies associated with Malignant Ascites. In females, the most common malignancies were ovarian, breast and unknown primary. In males, the most common were colon, pancreas and unknown primary. The major comorbid conditions were congestive heart failure (6.8%) and chronic pulmonary diseases (11.9%). Acute kidney injury (24.3%) followed by the intestinal obstruction (12.1%) constituted the majority complications in this cohort. On Multivariate analysis, the significant predictors of mortality were native American & Asian race, Solid organ tumors, pulmonary circulation disorders, acute kidney injury, intestinal obstruction and peritonitis. The inpatient mortality in this cohort was 12.9%.
Conclusion: There is a considerable inpatient burden and high inpatient mortality associated with Malignant Ascites in the United States, with potential demographic, geographic, and socioeconomic disparities. This analysis provides strong population-based statistics, which can be of use for clinicians, scientists, and policy makers.