Another “great mimicker”: FDG-PET/CT imaging findings of sarcoid-like reaction

A T K Kendi,D Bonta,D M Schuster,B J Barron,B Rathore,R K Halkar

doi:10.1259/bjrcr.20150060

Abstract

Sarcoid-like reaction (SLR) is a cause of non-caseating granulomas in some of the cancer patients with otherwise no signs or symptoms of sarcoidosis. SLR has been described in a variety of solid organ malignancies, including breast and lung cancer. SLR may result in hypermetabolic activity in 18-fludeoxyglucose positron emission tomography (PET)/CT scan, resulting in false positive reporting for malignancy. The purpose of this case series is to expose residents/practising physicians who interpret PET/CT to a series of cases illustrating findings of SLR.

Highlights

CASE REVIEW Case 1 The patient was a 63-year-old male with adenocarcinoma of the rectosigmoid junction and multifocal tubular adenoma of the right colon
Biopsy of one of these lymph nodes was consistent with sarcoid-like reaction (SLR)
The patient was found to have a large mass in the left iliac wing and was diagnosed with diffuse B-cell lymphoma

Summary

Introduction

CASE REVIEW Case 1 The patient was a 63-year-old male with adenocarcinoma of the rectosigmoid junction and multifocal tubular adenoma of the right colon. Findings: Post-therapy positron emission tomography (PET)/CT scan showed bilateral symmetric hilar and mediastinal enlarged lymph nodes with increased 18-fludeoxyglucose (FDG) activity (Figure 1). Biopsy of one of these lymph nodes was consistent with sarcoid-like reaction (SLR). Case 2 The patient was a 45-year-old female with multifocal multicentric left breast cancer, mcT2N0M0, Stage 2A, oestrogen receptor/progesterone receptor+, human epidermal growth factor 2(À). The patient had chemotherapy followed by left mastectomy and reduction of the right breast.

Results

Conclusion