Calcifying fibrous tumor of the esophagus in a myasthenia gravis patient: A case report

While calcifying fibrous tumor(CFT) was first described in soft tissue of children, it could be seen in wide range of age and variety of anatomic sites. In gastrointestinaltract, involvement of stomach and small intestine was more reported in literatures and according to our knowledge esophageal involvement was reported only once.Clinical manifestations and imaging are non-specific, making histopathology the only definite method for diagnosis. In microscopy, hypocellular hyalinized fibroconnectivetissue combined with lympho-plasma cell infiltration and psammomatous/ dystrophic calcifications are noted. Herein we report a case of calcifying fibrous tumor in the esophagus of 23 year-old lady, known case of myasthenia gravis, presenting with dysphagia. A 23 year-old lady, known case of myasthenia gravis for nine months referred toour center for thymectomy. The diagnosis of myesthenia gravis was already based on presence of clinical symptoms including ptosis, diplopia, dysphagia, and weakness aswell as high level of acetylcoline receptor antibody in serum sample. Chest x-ray was unremarkable with no evidence of space-occupying lesion .Consequently she underwent corticosteroid therapy and was candidate for thymectomy for better control of disease. During operation the surgeon discovered a bulged area in cervical esophagus incedentally, deviating trachea to left. Macroscopically the lesion had welldefined border with elastic to firm consistency, pale-tan homogeneous cut surface measuring 5 cm in greatest dimension. Microscopic examination revealed hyalinized collagen fibers with scattered lympho-plasmacytic infiltration and dystrophic/psammomatous calcifications. IHC study show negative result for ALK1 and focal weak positivity for CD34. Histomorpholoy and IHC findings were consistent with CFT. Thymus weighs 6g; appropriate for age and shows unremarkable histology. In 21 months follow-up, she has been symptom free with consumption of corticosteroids and no evidence of recurrence or postoperative complications is seen. In our case as a second report of esophageal CFT in the literature synchronous occurrence of the lesion and myasthenia gravis could suggest a probable causative association between these two clinical conditions and propose an immunological pathogenesis for CFT. Moreover with respect to surgical treatment and favorable outcome, both clinicians and pathologists should be aware of CFT as a differential diagnosis when considering other mesenchymal lesions in he GI tract.

Keywords:

esophagus , calcifying fibrous tumor , myasthenia