(a) A photograph of excised specimen shows a mass (arrows) with a central area of softening and red to purple discoloration bordered by a firm rim of gray to whitish tissue consistent with abscess. Also noted are two sharp linear fishbones (arrowheads) retrieved from the abscess
(b) A photomicrograph of histological examination of the mass at high-power field demonstrates colonies of Actinomyces (sulfur granule) (arrows), extensive infiltration of acute inflammatory cells, and hemorrhage (hematoxylin eosin (HE), original magnification, ×400)
Figure 2: Gross and microscopic features of fishbone-associated actinomycosis.