Retrospective chart analysis of incidental findings detected by18F-fluorodeoxyglucose-PET/CT in patients with cutaneous malignant melanoma

The effect of butylscopolamine on [18F]FDG uptake in the gastrointestinal tract is negligible and regionally variable

BACKGROUND

Butylscopolamine (or hyoscine butylbromide, trade name Buscopan^®) is occasionally administered as a premedication to reduce non-specific FDG uptake in the gastrointestinal tract based on its antiperistaltic effect. To date, there are no consistent recommendations for its use. The aim of this study was to quantify the reduction in intestinal and non-intestinal uptake by butylscopolamine administration and to derive relevance for clinical evaluation.

RESULTS

458 patients (PET/CT for lung cancer) were retrospectively reviewed. 218 patients with butylscopolamine and 240 patients without butylscopolamine had comparable characteristics. While the SUV_mean in the gullet/stomach and small intestine was significantly reduced with butylscopolamine, the colon and rectum/anus showed no difference. The liver and salivary glands showed a reduced SUV_mean, while skeletal muscle and blood pool were unaffected. An effect of butylscopolamine was particularly evident in men and patients under 65 years of age. There was no difference in the perceived confidence in the assessment of intestinal findings in the subjective evaluation, although in the butylscopolamine group further diagnostics appeared advisable more frequently.

CONCLUSIONS

Butylscopolamine reduces gastrointestinal FDG accumulation only in selected segments and, despite a significant effect, only to a small extent. A general recommendation for the use of butylscopolamine cannot be derived from these results, its use for specific issues could be considered individually.

FDG PET/CT to Detect Incidental Findings in Patients With Hepatocellular Carcinoma-Additional Benefit for Patients Considered for Liver Transplantation?

PURPOSE

FDG PET/CT has been described for noninvasive grading, detection of extrahepatic spread, and recurrence in hepatocellular carcinoma (HCC). As compared with localized imaging approaches (MRI, ultrasonography), FDG PET/CT not only focuses on the liver, but covers a long field of view from the base of the skull to the thighs, visualizing pathologic findings not related to HCC. The aims of this retrospective study were to (1) describe the frequency of relevant incidental findings on FDG PET/CT in HCC patients, (2) evaluate the impact on treatment strategy in HCC patients considered for liver transplantation, and (3) to discuss the role of FDG PET/CT in patients considered for transplantation in general.

METHODS

Four hundred thirty-nine FDG PET/CT examinations of 345 HCC patients were screened for incidental findings. The clinical information system was searched for examinations performed after FDG PET/CT and aimed at verification of incidental findings. Of 345 HCC patients, 81 patients were considered for liver transplantation. The impact of incidental findings was recorded separately for this subgroup.

RESULTS

One hundred one patients with incidental findings in 439 FDG PET/CT examinations were identified. The incidental findings comprised 22 neoplasms (9 malignant) and 52 inflammations. Liver transplantation was not performed because of an incidental finding on FDG PET/CT in 9 (11.1%) of 81 patients.

CONCLUSIONS

FDG PET/CT is capable of identifying relevant incidental findings (ie, secondary malignancy, benign tumors, and inflammation) in HCC patients and HCC patients considered for liver transplantation and thus influencing HCC patient management. FDG PET/CT might also be beneficial in patients considered for transplantation of different organs.

Incidental radiologic findings in breast cancer patients who undergo staging prior to neo-adjuvant chemotherapy

NCCN guidelines discourage the use of staging imaging for newly diagnosed patients with early breast cancer (BC). When performed, incidental radiologic findings of uncertain significance are often encountered. The purpose of this study was to compare incidental findings seen on staging imaging with distant recurrence in patients undergoing neo-adjuvant chemotherapy (NAC). 396 patients with BC who had NAC from 2008 to 2016 were identified from a prospectively maintained data base. Staging imaging was reviewed. Of 396 patients with BC treated with NAC, patients with a positive PET/CT for metastatic disease (n = 36, 9.1%), those that did not undergo staging imaging (n = 49, 12.4%), or those that did not have a reported incidental finding (n = 49, 12.4%) were excluded from analysis. Of the 262 patients who met criteria, mean age was 50 years (range: 26-88). 201 (76.7%) patients had stage I-II cancer, and 61 (23.3%) patients had stage III cancer. Overall, 146 (55.7%) patients had an incidental finding on imaging. 90 (34.4%) patients had one finding, 42 (16.0%) patients had two, and 14 (5.3%) patients had three or more findings. The majority of incidental findings were seen in the ovary/uterus (29.7%), followed by lung (18.4%), liver (10.3%), and bone (9.0%). 5 (3.4%) patients had additional imaging performed. At mean follow-up of 3.7 years (range: 0.7-10.8), 43 (15.6%) patients had a distant recurrence. Of these patients, only 5 (1.9%) patients had distant metastasis in the same organ that was initially thought to be an incidental finding. Our results suggest that breast cancer patients with incidental findings on preoperative staging imaging are unlikely to be indicative of sites for future metastasis.