Refractory Orbital Spindle Cell Carcinoma With Rapid Progression and Intracranial Extension.

Spindle cell carcinoma, also known as carcinosarcoma or sarcomatoid carcinoma, is a rare and aggressive variant of squamous cell carcinoma known by biphasic malignant histology with epithelial and mesenchymal differentiation. We report the case of a 72-year-old male presenting with progressive unilateral proptosis, upper eyelid swelling, and restricted ocular motility. Imaging showed a well-defined mass infiltrating multiple orbital structures, histopathologically supporting orbital spindle cell carcinoma after ruling out other mimics. After surgical debulking, followed by chemotherapy and radiotherapy, the tumor showed aggressive invasion with local infiltration, bone destruction, and intracranial extension, which ultimately led to the patient's death. This case underscores detection and management challenges in the primary orbital spindle cell carcinoma. This tumor's aggressiveness and resistance to traditional treatment approaches reveal the need for further investigation into its etiology and better management techniques.