Inflammatory myofibroblastic tumor of the trachea with concomitant granulomatous lymph node lesions

Abstract

We report herein the case of a 57-year-old lady who had two concomittant lesions, an inflammatory myofibroblastic tumor in the trachea, and severe granulomatous lesions in the adjacent hilar lymph nodes. While these two lesions shared histological and some immunohistochemical features lesions. They differed in terms of ALK-1 expression, which was positive in the tracheal tumor and negative in the lymph nodes. The discussion of the case circles around putative pathophysiological links between the lesions. The authors favor the idea that the lymph nodes present a sarcoid-like granulomatous reaction to the inflammatory myofibroblastic tumor in the trachea over a coexistence of two independent entities. However, no conclusive evidence for this interpretation can be presented based on the existing literature.

Figure 1

Representative image of the inflammatory myofibroblastic tumor (IMT) in the distant tracheal portion in a 57-year-old lady. (a) Overview of the lesion spanning three cartilage rings (PAS). (b) Note the partly spindly architecture of the lesion, with only very mild nuclear atypia and absent mitotic activity (H&E). Immunohistochemical documentation of CD68 expression (clone PGM1, (c)) and of ALK1 expression (d). The lower four panels (e)–(h) depict representative images of one of 15 peritracheal lymph nodes in the vicinity of the tracheal lesion shown in panel (a). (e) Overview over the deep sections through the lymph node, which shows that the granulomatous lesions largely replaces the lymph node and focally transgresses its capsule (H&E). (f) Higher power magnification of the marked area in (a). Note the striking granulomatous reaction replacing large parts of the lymph node, with extensive extracapsular extension into the adjacent adipose tissue. Immunohistochemical documentation of CD68 expression (clone PGM1, (g)) and absence of ALK1 expression (h). The space bars represent 0.5 cm in (a), 1 mm in (e), and 100 μm in (b)–(d) and (f)–(h).