A 54-year-old previously healthy man comes to the office due to several weeks of leg swelling. He has had no fever, chest pain, or dyspnea. The patient has a 40-pack-year smoking history but does not use alcohol or illicit drugs. He is afebrile and vital signs are within normal limits. On physical examination, there is symmetric pitting edema of the lower extremities bilaterally. The abdomen is soft and nondistended. A mobile left flank mass can be palpated. There are several vertically oriented tortuous veins on the lower abdominal wall. Which of the following structures is most likely obstructed in this patient?

Question

A 54-year-old previously healthy man comes to the office due to several weeks of leg swelling.  He has had no fever, chest pain, or dyspnea.  The patient has a 40-pack-year smoking history but does not use alcohol or illicit drugs.  He is afebrile and vital signs are within normal limits.  On physical examination, there is symmetric pitting edema of the lower extremities bilaterally.  The abdomen is soft and nondistended.  A mobile left flank mass can be palpated.  There are several vertically oriented tortuous veins on the lower abdominal wall. Which of the following structures is most likely obstructed in this patient?

Quizplus · Accepted Answer

11ec160b_3a4d_2b73_9249_85ec01f1f410_MD0001_00 This patient's symmetric bilateral lower extremity pitting edema and tortuous abdominal veins are concerning for an inferior vena cava (IVC) obstruction, which, in the setting of a left-sided flank mass, suggests renal cell carcinoma (RCC) with extension into the IVC. RCC accounts for >90% of all malignancies arising in the kidney and is highly associated with smoking. Patients with RCC classically have a triad of flank pain, palpable mass, and hematuria, although many remain asymptomatic until the disease is advanced. RCC is a highly vascular tumor that invades the renal vein in up to 25% of cases. IVC obstruction can occur due to intraluminal extension and thrombus formation, rather than mass effect from the tumor itself. The obstruction can occur acutely or gradually over time. In chronic cases, collateral venous circulation may develop based on the site of the obstruction. Prominent abdominal wall collateral veins, as in this patient, suggest obstruction of the upper segment of the IVC. (Choices A, B, and E) The femoral, iliac, and saphenous veins are too low in the legs to produce significant abdominal wall collateral veins if obstructed. Obstruction of these veins would be more likely to cause varices on the legs, thighs, and hips. In addition, unilateral (rather than bilateral) lower extremity edema would be expected. (Choice D) Obstruction of the portal vein is most commonly associated with severe hepatic cirrhosis. Affected patients have shunting of blood through portocaval anastomoses, leading to hemorrhoids, esophageal varices, and caput medusae about the umbilicus. They may also have ascites. Educational objective: Renal cell carcinoma tends to invade the renal vein; inferior vena cava obstruction can occur by intraluminal extension of the tumor. Obstruction of the inferior vena cava produces symmetric bilateral lower extremity edema, often associated with prominent development of venous collaterals in the abdominal wall. __________ References: Important surgical considerations in the management of renal cell carcinoma (RCC) with inferior vena cava (IVC) tumour thrombus. (http://www.ncbi.nlm.nih.gov/pubmed/22540179)

A 54-Year-Old Previously Healthy Man Comes to the Office Due