We performed this prospective study to evaluate the correlation of
interleukin-6 serum levels with preoperative constitutional symptoms and immunologic abnormalities, and the possible role played by this
cytokine in
tumor recurrence. Eight patients with atrial
myxoma were evaluated at our institution from July 1993 to November 1998. We measured their
interleukin-6 serum levels by
enzyme-linked
immunosorbent assay method preoperatively and 1 and 6 months after surgery. Two of the cases involved recurrent
tumor, 1 patient had undergone his 1st surgery at a different institution and died during the 2nd procedure, so his data were incomplete. Preoperatively the whole group of patients had elevated
interleukin-6 serum levels. Although patients with a 1st occurrence of
tumor demonstrated a positive correlation between
interleukin-6 serum level and
tumor size, the 2 patients with recurrent
tumors appeared to have higher
interleukin-6 levels regardless of
tumor size. Once the
tumor was surgically removed,
interleukin-6 levels returned to normal values, and this was associated with regression of clinical manifestations and immunologic features. According to our study, the overproduction of
interleukin-6 by cardiac
myxomas is responsible for the constitutional symptoms and immunologic abnormalities observed in patients with such
tumors and might also play a role as a marker of recurrence. This study also suggests that recurrent cardiac
myxomas form a subgroup of cardiac
myxomas with a highly intrinsic aggressiveness, as implied by their greater
interleukin-6 production despite their smaller size. Further studies are needed to confirm these results.