Learn about an inflammatory pseudotumor, which is a heterogenous lesion of unknown etiology that may mimic a malignancy with local destruction of tissue, recurrence following excision, and the development of multiple foci. Although not uncommonly reported, this lesion remains controversial and enigmatic. Recent investigations into the molecular origin of these pseudotumors reveals that some lesions may possess a chromosomal translocation notable in some lymphomas, indicating a resemblance to a malignant process; however, other pseudotumors appear to originate from an infectious etiology.
Methods
Two cases are presented involving unusually aggressive, benign nasopharyngeal lesions that were notable for invasion of the parapharyngeal and masticator space, as well as involvement of the clivus and temporal bone with extension through the skull base.
Results
Exhaustive pathologic examination of these erosive lesions did not reveal a malignant process. Immunohistochemical and molecular diagnostic testing ruled out any hematologic or clonal lymphoid processes. In one case, biopsies noted a mixed population of bacteria in a setting of inflammation. Long-term intravenous antibiotics were prescribed. This pseudotumor remains persistent, though the clinical course has been stable. In the second case, the nasopharyngeal pseudotumor was treated with radiation therapy resulting in a complete remission.
Conclusions
The inflammatory pseudotumor remains a diagnostic dilemma. The question remains whether these pseudotumors represent a true neoplastic process or may encompass a diverse spectrum of multiple lesions that mimic a malignancy. Surgery, radiation, and treatment with steroids and antibiotics has each yielded some success though results are discordant.
FULL TEXT