Which organ is included with esophagus and rectum as clinically important sites for portacaval anastomoses?

• A. Liver
• B. Stomach
• C. Spleen
• D. Pancreas

Answer: (A)

Portocaval (portosystemic) anastomoses form where the portal venous system can drain directly into the systemic (caval) venous system. The most clinically important collateral routes appear when portal pressure rises, producing varices at vulnerable junctions. The esophagus and rectum are classic sites because their veins directly link portal tributaries (like the left gastric and superior rectal veins) with systemic veins (esophageal and middle/inferior rectal veins), leading to varices.

The liver is included because there can also be intrahepatic portosystemic shunts—connections between portal venous branches and hepatic veins within the liver itself. These shunts bypass hepatic parenchyma and drain into the systemic circulation, representing another clinically relevant portosystemic pathway. Other organs listed don’t form major, typical portosystemic collaterals in the setting of portal hypertension.

So, the liver is a correct site alongside esophagus and rectum for portacaval anastomoses because it can host intrahepatic collateral channels that divert portal blood into the systemic circulation.