A role of 18F-fluorodeoxyglucose positron emission/computed tomography in a strategy for abdominal wall metastasis of colorectal mucinous adenocarcinoma developed after laparoscopic surgery

FDG PET/MRI in a Case of Isolated Abdominal Incisional Site Metastasis After Laparoscopic Surgery for Colon Cancer

ABSTRACT

Abdominal-wall metastasis following laparoscopic surgery for colorectal cancer is rare. We describe FDG PET/MRI findings in a case of isolated abdominal incisional site metastasis after laparoscopic surgery for colon cancer. The abdominal-wall metastasis showed slight hyperintensity on T2-weighted fat-suppressed image and intense focal FDG uptake on PET. This case demonstrates the usefulness of FDG PET/MRI in detecting the atypical metastasis from colon cancer.

A case of Schloffer tumor with rapid growth and FDG-PET positivity at the port site of laparoscopic sigmoidectomy for colon cancer

Background

Schloffer tumor is a foreign body granuloma in the abdominal subcutaneous layer that develops due to a foreign body such as suture from several months to years postoperatively. Herein, we report a case of a rapidly growing Schloffer tumor with F-18 fluorodeoxyglucose (FDG) positron emission tomography (PET) positivity at the port site of laparoscopic sigmoidectomy for colon cancer.

Case presentation

An 85-year-old man, who underwent laparoscopic sigmoidectomy for stage IIIa sigmoid colon cancer 10 months ago, was referred to our hospital with complaints of a growing mass in the abdominal wall. The tumor was palpable at the right-sided abdominal wall corresponding to the port site of laparoscopic sigmoidectomy. The tumor rapidly grew for 2 months. Computed tomography showed a ring-enhanced mass at the right-sided abdominal wall. PET examination revealed high accumulation of FDG in the tumor. Tumor resection was performed due to suspected port site recurrence. The pathological diagnosis was inflammatory granuloma, so-called Schloffer tumor.

Conclusion

In the era of laparoscopic surgery, Schloffer tumor may be one of the differential diagnoses for rapidly growing tumor with FDG-PET positivity at the port site in postoperative patients with advanced colorectal cancer.

Use of (18)F-fluorodeoxyglucose positron emission tomography-computed tomography to aid in diagnosing intestinal adenocarcinoma in 2 rhesus macaques (Macaca mulatta)

Two aged female rhesus macaques (Macaca mulatta) presented with weight loss and intermittent inappetence. The signalment and constellation of clinical signs led clinicians to suspect the presence of intestinal adenocarcinoma. Because of each animal's advanced age and inconclusive radiographic findings, a noninvasive diagnostic tool was preferred over exploratory laparotomy to assist in determining a diagnosis. Consequently, 2-[(18)F]fluoro-2-deoxy-d-glucose (FDG) positron emission tomography-CT (FDG-PET-CT) was chosen to aid in confirming a suspicion of gastrointestinal adenocarcinoma in both animals. FDG is a glucose analogue labeled with fluorine-18 and is taken up by highly metabolically active cells, as observed in many cancers. Tomography revealed an annular constriction of the small intestine with focal FDG uptake in one animal, and an FDG avid transmural mass in the ascending colon of the second animal. Necropsy later confirmed both sites to be adenocarcinomas. This report supports the use of FDG-PET-CT as an adjunct to conventional radiography in the diagnosis of intestinal adenocarcinoma in nonhuman primates.