Granulomatous reaction to injectable hyaluronic acid (Restylane) diagnosed by fine needle biopsy

The hyaluronic acid (HA) derivative Restylane is now the most common injectable soft tissue filler used for facial wrinkle augmentation. Although it is generally well tolerated and absorbed within months, nodule formation at the injection site has been documented. A 62-year-old woman with a history of carcinoma of the breast six years previously was referred to a fine needle aspiration (FNA) clinic for biopsy of a subcutaneous facial nodule. On palpating the nodule six weeks prior to presentation she was referred for ultrasound examination; findings were reported as being consistent with a lymph node, raising concern of possible metastatic carcinoma of the breast. Serendipitously the same ultrasound examination led to discovery of a thyroid nodule that was aspirated and found to be papillary carcinoma, broadening the differential diagnosis of the facial nodule to metastatic thyroid carcinoma. On physical examination the lesion was a 1 cm subcutaneous nodule overlying the lower third of the mandible, a location felt to be consistent with a slightly “high” submental node. However, the nodule had irregular contours on palpation, and although it could be moved over the underlying bone, seemed to be fixed to the overlying skin. No cellular material was obtained by initial sampling with a 27G needle. After instillation of local anaesthetic, two samples were taken with a …