Leptomeningeal carcinomatosis as only pathological finding at FDG-PET/CT in case of tumor marker elevation in breast cancer

Abstract

Leptomeningeal carcinomatosis is an infrequent disease and although its treatment is palliative, earlier diagnosis will lead to prolonged survival and improve functional outcome. Whole-body FDG-PET allows the entire spinal cord to be examined noninvasively, so close attention should be paid to the spinal canal, since these lesions can easily be mistaken for physiologic uptake, sometimes there is no clinical suspicion and may occur without concurrent active cancer. We present a female patient with a history of carcinoma of the breast, who presented an elevation of serum tumor marker CA 15-3. An FDG-PET/CT study only revealed multiple abnormal uptake at the vertebral foramen at thoracic and lumbosacral regions suggesting leptomeningeal metastases that were confirmed by MRI and cerebrospinal fluid cytology.

Keywords: Breast cancer; FDG-PET/CT; leptomeningeal carcinomatosis; metastases.

Figure 1

(a) Sagittal PET and fused PET/CT images showing pathological FDG uptake at the level of T2 vertebra (thin arrow), T6 (thick arrow) and T8 (dotted arrow). (b) Focal area of uptake at the level of sacrum (arrow) at the sagittal PET and fused PET/CT images. (c) Sagittal slice of gadolinium contrast spinal MRI showing linear (thin arrows) and nodular (thick arrow) leptomeningeal enhancement over the posterior surface of the spinal cord.