Squamous cell carcinoma arising from a Dacryocystorhinostomy ostium 5-years after the Surgery

The case is to report an exceptionally rare occurrence of squamous cell carcinoma arising within a dacryocystorhinostomy (DCR) ostium long after the initial surgery. A 43-year-old female presented with left-eye proptosis and diplopia of six-month duration. Endoscopic examination revealed a vascular pink lesion within the ostium and another mass lesion in the nasolacrimal duct (NLD) opening in the inferior meatus. Computed tomography imaging demonstrated an isodense, irregular mass in the inferior quadrant of the anterior orbit, predominantly extraconal, extending to the medial orbit and then into the previous DCR ostium. An incisional biopsy was taken from the inferior orbit, which was reported as non-keratinizing squamous cell carcinoma. Five years earlier, the patient had undergone a routine endoscopic DCR for primary acquired nasolacrimal duct obstruction (PANDO), during which a focal intrasaccal granuloma with dacryoliths was noted. The lesion was excised and confirmed to be a granuloma. A histopathological re-review of this granuloma revealed granulation tissue with two focal areas of epithelial dysplasia. A combined external and endoscopic approach to the lacrimal sac tumors helped achieve a complete surgical excision. Lacrimal sac granulomas encountered during a DCR surgery could harbor suspicious foci of dysplasia.