This unfortunate lady has Carcinoid Syndrome. It is speculated that this lesion doesn't start to cause symptoms until it is metastatic to the liver. This explains the patients hepatomegaly. Metastatic disease to the liver is necessary because the liver is a good metabolizer of 5-HT (serotonin) the active agent that causes all of a patients symptoms. To get systemic effects it must get past the liver. Further evidence of metastatic disease is exhibited by the murmur of tricuspid insufficiency. This is speculated to occur secondary to high serotonin levels affecting the tricuspid valve causing significant valvular insufficiency (3) as is exemplified by the pulsatile liver on examination. Finally, a further sign of metastatic disease is the evidence of lung parenchymal disease as suggested by the symptoms of wheezing. Again this is presumed hematogenous seeding from the liver, through the right side of heart and finally into the lung (2).
Most carcinoid's can be picked up with a urine collection for 5-hydroxyindoleacetic acid (5-HIAA) which is a metabolite of serotonin (5). Usually, serum serotonin levels are also elevated. However, many gastric carcinoid tumors lack the aromatic L-amino acid decarboxylase and convert 5-hydroxytryptophan to serotonin with low efficiency. Since 5-HTP is not metabolized to 5-HIAA, urinary studies could be negative unless you look for this specific molecule.
Treatment (4,6-9) is not very promising though Octreotide SQ injections can provide relief. This can be coupled with Histamine receptor blockers (H-1 blocker = diphenydramine and H-2 blocker = ranitidine). Diarrhea is treated symptomatically with anti-motility agents. Meter-dosed inhalers can help with the wheezing and associated dyspnea. There have been cases of hepatic artery embolization of the tumor in patients in which the tumor is found early and in one lobe of the liver. Surgery, hepatic artery embolization and chemotherapy have been used to reduce the tumor burden. Unfortunately, the cardiac valve abnormalities are irreversible.
Median survival once a patient develops flushing is approximately 2 1/2 years. Patients who excrete >800 micromol/day (>150 mg/d) have approximately one year survival (1).