False-positive fluorine-18 fluorodeoxy-D-glucose positron emission tomography imaging caused by retained gauze in a woman with recurrent ovarian cancer: A case report

We report a case of a 47-year-old woman with a false-positive [18F]fluoro-2-deoxy-D-glucose (FDG) positron emission tomography (PET) result caused by retained gauze during resection of liver metastasis for a Stage IV ovarian cancer at primary cytoreductive surgery. She achieved complete remission and remained free of progression for seven years. Owing to elevation of CA-125, computed tomography and PET studies were performed, and both showed two potentially resectable lesions. One was located ventral to the diaphragmatic surface of the left hepatic lobe and the other was around the gauze at the right hepatorenal fossa. During surgical intervention, the left supraheptic tumor was excised and the gauze with surrounding granulation was removed. However, the former proved to be recurrent ovarian cancer with the latter proven false-positive. This case demonstrates that PET results should be interpreted with caution in differentiating a benign inflammatory process from malignant abnormalities, especially in regions with a high probability of granulomatous lesions.

PET; False posIitive; Ovarian neoplasms; Gauze

[1] Berek J.S.: "Epithelial ovarian cancer". In: "Practical Gynecologic Oncology". Berek J.S., Hacker N.F. (eds.) 3rd edition, Philadelphia, Lippincott Williams & Wilkins, 2000, 504.

[2]Niloff J.M., Knapp R.C., Lavin P.T., Malkasian G.D., Berek J.S., Mortel R. et al.: "The CA 125 assay as a predictor of clinical recurrence in epithelial ovarian cancer". Am. J. Obstet. Gynecol., 1986, 155, 56.

[3] Rubin S.C., Hoskins W.J., Hakes T.B., Markman M., Reichman B.S., Chapman D. et al.: "Serum CA125 levels and surgical findings in patients undergoing secondary operations for epithelial ovarian cancer". Am. J. Obstet. Gynecol., 1989, 160, 667.

[4] Rustin G.J.S., Marples M., Nelstrop A.E., Mahmoudi M., Meyer T.: "Use of CA 125 to define progression of ovarian cancer in patients with persistently elevated levels". J. Clin. Oneal., 2001, 19, 4054.

[5] Clarke-Pearson D.L., Bandy L.C., Dudzinski M., Heatson D., Creasman W.T.: "Computed tomography in evaluation of patients with ovarian carcinoma in complete clinical remission. Correlation with surgical-pathologic findings". JAMA, 1986, 255, 627.

[6] Silverman P.M., Osborne M., Dunnick N.R., Bandy L.C.: "CT prior to second-look operation in ovarian cancer". Am. J. Roentgenol., 1988, 150, 829.

[7] Prayer L., Kainz C., Kramer J., Stiglbauer R., Schurawitzki H., Baldt M. et al.: "CT and MR accuracy in the detection of tumor recurrence in patients treated for ovarian cancer". J. Comput. Assist. Tomogr., 1993, 17, 626.

[8] Funt S.A., Hricak H., Abu-Rustum N., Mazumdar M., Felderman H., Chi D.S.: "Role of CT in the management of recurrent ovarian cancer". Am. J. Roentgenol., 2004, 182, 393.

[9] Nakamoto Y., Saga T., lshimori T., Mamede M., Togashi K., Higuchi T. et al.: "Clinical value of positron emission tomography with FOG for recurrent ovarian cancer". Am. J. Radial., 2001, 176, 1449.

[10] Torizuka T., Nobezawa S., Kanno T., Futatsubashi M., Yoshikawa E., Okada H. et al.: "Ovarian cancer recurrence: role of wholebody positron emission tomography using 2-[fluorine-18]-fluoro-2-deoxy-D-glucose". Eur. J. Nuclear Med. Mal. Imaging, 2002, 29, 797.

[11] Bristow R.E., Carmen M.G., Pannu H.K., Cohade C., Zahurak M.L., Fishman E.K. et al.: "Clinically occult recurrent ovarian cancer: patient selection for secondary cytoreductive surgery using combined PET/CT". Gynecol. Oneal., 2003, 90, 519.

[12] Lai C.H., Huang K.G., See L.C., Yen T.C., Ma S.Y., Tsai C.S. et al.: "Restaging of recurrent cervical cancer with dual-phase positron emission tomography". Cancer, 2004, 100, 544.

[13] Munkarah A., Levenback C., Wolf JK., Bodurka-Bevers D., Tortolero- Luna G., Morris R.T. et al.: "Secondary cytoreductive surgery for localized intra-abdominal recurrences in epithelial ovarian cancer". Gynecol. Oneal., 2001, 81, 237.

[14] Tay E.H., Grant P.T., Gebski V., Hacker N.F.: "Secondary cytoreductive surgery for recurrent ovarian cancer". Obstet. Gynecol., 2002, 99, 1008.

[15] Ilknur A., Stokkel M.P.M., Pauwels E.K.J.: "Positron emission tomography with 2-[18F]fluoro-2-deoxy-D-glucose in oncology". J. Cancer Res. Clin. Oneal., 2000, 126, 560.

[16] Kubota R., Kubota K., Yamada S., Tada M., Ido T., Tamahashi N.: "Microautoradiographic study for the differentiation of intratumoral macrophages, granulation tissues and cancer cells by the dynamics of fluorine-18-fluorodeoxyglucose". J. Nucl. Med., 1994, 35, 104.

[17] Strauss L.G.: "Fluorine-18 deoxyglucose and false positive results:A major problem in the diagnostics of oncological patients". Eur. J. Nucl. Med., 1996, 23, 1409.

[18] Yamada S., Kubota K, Kubato R., Ido T., Tamaha_shi N.: "High accumulation of fluorine-18-fluorodeoxyglucose in turpentineinduced inflammatory tissue". J. Nucl. Med., 1995, 36, 1301.

[19] Yen R.F., Chen M.L., Liu F.Y., Ko Y.L., Chieng P.U., Su C.T "False-positive 2[F-18]-fluoro-2-deoy-D-glucose positron emission tomography study for evaluation of focal pulmonary abnormalities". J. Formos. Med. Assoc., 1998, 97, 642.

[20] Knight S.B., Delbeke D., Stewart J.R., Sandler M.P.: "Evaluation of pulmonary lesions with FOG-PET". Chest, 1996, 109, 982.

[21] Sakamoto H., Nakai Y., Ohashi Y., Okamura T., Ochi H.: "Positron emission tomographic imaging of head and neck lesions". Eur. Arch. Otorhinolaryngol., 1997, 254 (suppl. I), Sl23.

[22] Stokkel M.P., Bongers V., Hordijk G.J., van Rijk P.P.: "FOG positron emission tomography in head and neck cancer: pitfall or pathology?". Clin. Nucl. Med., 1999, 24, 950.

[23] Lorenzen J., de Wit M., Buchert R., Igel B., Bohuslavizki K.H.: "Granulation tissue: pitfall in therapy control with F-18-FDG PET after chemotherapy". Nuklearmedizin, 1999, 38, 333.