Pleomorphic adenoma of the left lacrimal gland recurred and transformed into myoepithelial carcinoma after multiple operations: A case report

BACKGROUND: Myoepithelial carcinoma (MC) is a clinically rare malignancy, there is controversy regarding its etiology and its biological behavior is not fully elucidated. Extensive surgical resection is the main treatment method. We describe a case of pleomorphic adenoma (PA) with multiple postoperative recurrences after malignant transformation, and the history of the disease in this patient was more than 20 years. Complete resection during the first surgery of PA and long-term postoperative follow-up is necessary. CASE SUMMARY: A 34-year-old male with PA and a history of 5 postoperative recurrences over 21 years, each surgically removed, presented 15 d ago with headache, nasal congestion, protrusion of the right eyeball and loss of vision in the right eye, with progressively worsening symptoms. The patient underwent surgery, and MC was confirmed by pathology examination. A small PA component was locally visible under light microscope. The patient had a recurrence of the tumor 2 mo after surgery and underwent surgical resection. CONCLUSION: During the first operation for PA, care should be taken not to rupture the envelope to prevent tumor cell implantation, and when complete resection is not possible due to the anatomical site, postoperative radiotherapy is necessary to control the lesion and prevent infiltration and malignant transformation of the tumor to MC. Computed tomography and magnetic resonance imaging is important for establishing diagnosis and developing a treatment plan.