Histologic changes in dog lymph nodes after endolymphatic application of bleomycin oil suspension

Bleomycin oil suspension (Oil-Bleo) was injected endolymphatically in a dog experiment. The drug remained in lymph nodes over many weeks in detectable concentrations. The histologic changes in these lymph nodes were examined and compared with 3 controls (aqueous Bleomycin, Lipiodol, and no treatment). Granulomatous reaction, microabscesses, and small necrotic foci were observed. After a month, fibrosis was detectable in all lymph nodes. The damage to microscopic lymph node structures after Oil-Bleo was moderate. These findings suggest that Oil-Bleo may be useful in local treatment of lymph node metastases.