Neck as mediastinal extension: Diagnosis of sarcoidosis by core biopsy of cervical lymph nodes.

Abstract

Sarcoidosis is a multi-system granulomatous disease. The diagnostic procedures for histological confirmation are invasive and a less invasive approach to diagnostic pathway is warranted. The utility of diagnostic value of neck ultrasound was retrospectively evaluated. A histological diagnosis was made by ultrasound-guided head and neck core biopsy to confirm clinically and radiologically suspected sarcoidosis. Twenty-five patients were referred for sonographic evaluation of the head and neck after CT scan in an attempt to avoid the use of more invasive tests. These patients had mediastinal adenopathy, but not clinically apparent neck nodes. Where no cervical lymph node suitable for biopsy was seen, parotid glands were biopsied if deemed abnormal. A diagnosis of sarcoidosis was made in all cases where a core biopsy of cervical lymph nodes was attempted. The cervical lymph nodesin this cohort were not particularly enlarged, short-axis dimensions being less than 10mm in majority, and they did not have any sonographic appearances to mark them as pathological. Nevertheless histological examination revealed non-caseating granulomas in all cases. In further two cases, where no neck nodes were seen, a histological diagnosis of sarcoidosis was made from biopsy of diffusely abnormal parotid glands. Given the clear advantages of cervical diagnosis in terms of invasiveness and economy compared to mediastinal alternatives, it is suggested that where the expertise for core biopsy of normal-sized cervical lymph nodes is readily available, the technique may be considered as a first-line investigation for the diagnosis of sarcoidosis.