F-18 fluorodeoxyglucose PET in Fournier gangrene

Fasciola Hepatica Mimicking Malignancy on 18F-Fluorodeoxyglucose-Positron Emission Tomography/Computed Tomography

A 48-year-old female with complaints of gastrointestinal symptoms such as abdominal pain, fatigue, vomiting, nausea, and weight loss was diagnosed with neuroendocrine tumor after removal of a 2 mm lesion from the stomach with endoscopic biopsy. Her magnetic resonance imaging that was performed due to on-going symptoms showed multiple linear hypointense lesions in the liver. Positron emission tomography/computed tomography (PET/CT) scan was performed for differential diagnosis, which showed high fluorodeoxyglucose (FDG) uptake in these lesions. Clinical and laboratory findings revealed the final diagnosis as Fasciola hepatica. The imaging features of this case is presented to aid in differentiating this infectious disease from malignancy and avoid misdiagnosis on FDG-PET/CT.

Severe Fournier's gangrene in a patient with rectal cancer: case report and literature review

Background

Fournier’s gangrene in the setting of rectal cancer is rare. Treatment for Fournier’s gangrene associated with rectal cancer is more complex than other cases of Fournier’s gangrene. We report on a patient with severe Fournier’s gangrene in the setting of locally advanced rectal cancer who was treated with a combined modality therapy.

Case presentation

A 65-year-old man presented with general fatigue and anal pain. The medical and surgical histories were unremarkable. A black spot on the perineal skin surrounded by erythema was found on physical examination, suspicious for Fournier’s gangrene. Computed tomography scan showed a rectal tumor invading into the bladder (clinically T4bN2M0) and abscess formation with emphysema around the rectum. He was thus diagnosed with locally advanced rectal cancer and Fournier’s gangrene with a severity index score of 12 points. We created a diverting loop colostomy of the transverse colon and performed extensive debridement of the perineum and perianal area. Fifty days later, the patient underwent radical total pelvic exenteration with sacrectomy. In addition, reconstruction of the soft tissue defect was performed using the rectus muscle, the gluteus maximus muscle, and the femoral muscle. Histopathological findings of the specimen were as follows: the tumor was a moderately adenocarcinoma with invasion to the bladder and the prostate (T4b), metastases to four resected lymph nodes (N2), and lymphovascular invasion. There were no major postoperative complications, and the patient was discharged 108 days postoperatively.

Conclusions

We report a rare case of locally invasive rectal cancer associated with Fournier’s gangrene. This case highlights a usual cause of Fournier’s gangrene. Physicians should be cognizant not only of the more common condition but also of the rare presentations including those associated with rectal cancer.

FDG PET/CT images demonstrating Fournier gangrene with bilateral pelvic muscle extension in a patient with recurrent rectosigmoid cancer

A 71-year-old male patient with Parkinsonism was referred for an F-FDG PET/CT scan for suspicious recurrence of rectosigmoid adenocarcinoma. The FDG PET/CT scan revealed increased FDG uptakes in the lower pelvic region around the wall of the rectal stump, with extension to the bilateral pelvic sidewalls and the right gluteous minimus muscle. In addition, multiple small air bubbles were noted in the lesions on the attenuation CT images. Fournier gangrene was diagnosed. After treatment with intravenous antibiotics and debridement with sigmoidoscopic irrigation, the patient was discharged and remained uneventful during clinical follow-up for 50 days.