Lymphomatoid granulomatosis (LyG) was first described in 1972 and survives as a distinct clinicopathologic entity today. Initially considered a proliferation that had features of both Wegener granulomatosis (currently granulomatosis with polyangiitis) and lymphoma, most cases of LyG are now considered a T cell-rich, EBV-related B-cell lymphoma.^1,2,3,4

All cases of LyG have a mixed population of atypical B lymphocytes and typical small T lymphocytes, which may predominate. Vascular invasion (angiocentricity) is a requirement for diagnosis. It is still debated if the presence of EBV by in situ hybridization is essential for the diagnosis, because sampling may preclude identification of these cells if they are not numerous or if the sample is small.^1,2,3

Although skin and nervous system involvement are common, it is debated if LyG can occur without lung involvement. Series of pathologically documented LyG show no case without lung involvement.⁴ The relatively high frequency of the development of nodal lymphoma in earlier studies has been questioned, as they were reported prior to the era of molecular diagnostics,² and recent series show no case with nodal lymphoma.⁴

Men are more frequently involved than are women, at a rate of about 2:1. The mean age at presentation is between 40 and 50 years, although there is a wide range. The skin and central nervous system are involved in about 1/3 to ½ of patients. Other sites of involvement include the upper respiratory tract, kidney, gastrointestinal tract, eye, adrenal gland, and liver.⁴

Fever and cough are the most common pulmonary symptoms.

Immune disorders and other malignancies have been reported in association with LyG in about 5% of patients.²

Chest x-ray and computed tomographic scans show parenchymal lesions that are usually multiple and predominate in the lower lobes. Cavitation may be seen by computed tomography but is not present on chest x-ray.³