Squamous cell carcinoma in the lacrimal sac presenting as proptosis: a case report.

KEY CLINICAL MESSAGE Lacrimal sac squamous cell carcinoma is extremely rare, and treatment guidelines remain unclear. In select cases, wide en bloc resection combined with prosthetic rehabilitation may offer the best outcomes. This case report advocates a multidisciplinary, consensus-driven approach centered on patient outcomes, with the use of a 3D printed skull with the benefits of gaining insight and providing visualisation pre-operatively. In addition, we want to emphasise the importance of speed in diagnosis and treatment in this report, in order to ensure optimal care.

SUMMARY Lacrimal sac squamous cell carcinoma is a rare epithelial malignancy often misdiagnosed as chronic dacryocystitis, delaying treatment. This article reports a pT4bN2bM0 case in a 67-year-old man treated with wide en bloc resection, yielding clear margins (>6 mm) and found after 4 months from initial symptoms. A 3D-printed skull model aided preoperative visualization. Histology revealed lymphovascular invasion and broad nests of atypical squamous cells with dyskeratosis and necrosis, confirming lacrimal origin. Adjuvant chemoradiotherapy followed. At 8-month follow-up, no signs of local, regional, or distant recurrence were observed.