Suture Granuloma With False-Positive Findings on FDG-PET/CT Resected via Laparoscopic Surgery

Abstract

A 61-year-old woman who had undergone total hysterectomy 16 years previously exhibited a pelvic tumor on computed tomography (CT). F-18 fluorodeoxyglucose (FDG) combined positron emission tomography (PET)/CT imaging revealed a solitary small focus of increased FDG activity in the pelvis. A gastrointestinal stromal tumor originating in the small intestine or another type of tumor originating in the mesentery (desmoid, schwannoma, or foreign body granuloma) was suspected; therefore, laparoscopic resection was conducted. A white, hard tumor was found to originate from the mesentery of the sigmoid colon and adhered slightly to the small intestine. The tumor was resected with a negative margin, and the pathologic diagnosis was suture granuloma. The possibility of suture granuloma should be kept in mind in cases of tumors with positive PET findings and a history of surgery close to the lesion. However, it is difficult to preoperatively diagnose pelvic tumors using a biopsy. Therefore, considering the possibility of malignancy, it is necessary to achieve complete resection without exposing the tumor.

Suture granuloma masquerading as primary ovarian malignancy: a case report

“…Takeshita N et al, reported a case of pelvic suture granuloma in a 61-year-old female with a prior history of total hysterectomy for uterine myoma 16 years back and caesarean delivery 35 years back. 4 In this case, suture granuloma developed two years after the surgery. Authors opine that the inflammatory reaction is initiated in the early post-operative phase in all cases, but patients may become symptomatic after a variable time period.…”

“…Radiologically, suture granulomas can be mistaken as either primary malignancy or tumour recurrence in a surgically treated case of cancer. 1,[4][5][6][7][8] Rettenbacher et al, stated that suture granulomas would characteristically appear as hypoechoic lesion with hyperechoic single or double lines on USG. 9 But, most of the cases lack specific USG findings, like in this case.…”

“…Even, 18F-FDG PET is fraught with false-positive results. [4][5][6][7][8] de Sousa Leão and colleagues suggested that the specificity of 18F-FDG PET increases, when its findings are interpreted in conjunction with levels of serum tumor markers. 5 In the present case, CA-125, a marker of ovarian malignancy, was raised, but not markedly raised as in most cases of ovarian malignancy.…”

Silk suture granuloma with false-positive findings on PET/CT accompanied by peritoneal metastasis after colon cancer surgery

“…Including the present case, there have been 7 reports of 9 cases of suture granuloma with false-positive postoperative PET/CT findings [4] , [5] , [6] , [7] , [8] , [9] , [10] ( Table 1 ). As can be seen in Table 1 , the interval between surgery and suture granuloma occurrence varied significantly, and suture granuloma can be found several decades after surgery.…”

Diagnostic value of integrated 18F-fluoro-2-deoxyglucose positron emission tomography/computed tomography in recurrent epithelial ovarian cancer: accuracy of patient selection for secondary cytoreduction in 134 patients

“…In our results, the mean maxSUV of foreign body granuloma was 4.41 (range, 2.2–7.2). A number of case reports have been published on this entity in various carcinomas [ 23 24 25 ]. However, only 1 or 2 cases were reported in each study and no large numbers of cases were identified, as in this study.…”