Giant Solitary Fibrous Tumor: Case Series and Effective Management

Background: Solitary fibrous tumors are rare tumors. The first reported case series of solitary fibrous tumors documented only 6 cases among 6,348 cases underwent pathological examination at Mayo Clinic tissue registry in 65 years. Subsequent published reports showed the rarity of the disease. These tumors have variable radiological appearance intermixes with many other tumors. Multidisciplinary team is needed to achieve maximum control of the disease.

Cases Description: We present four cases of giant solitary fibrous tumor:

Case 1: A 35-year-old male (Fig. 1) presented with left side hearing loss and swallowing disorder. He was found to have a mass of 4.4, 5.7, and 5.7 cm in the three dimensions originated from the sigmoid sinus with projection to the posterior fossa and middle fossa. He underwent two-staged surgeries. The first surgery was achieved through a transmastoid and translabyrinthine approach. Though the patient underwent preoperative embolization, the tumor was bloody. In the second stage, retrosigmoid approach was added achieving near-total resection. This was followed by 60-Gy radiation in 30 fractions. Swallowing disorder improved. No recurrence with 2-year follow-up period.

Case 2: A 44-year-old male presented with a headache and papilledema. He was found to have a mass of 5.9, 5.0, and 7.8 cm in the three dimensions based on the tentorium and transverse sinus with supra and infratentorium projections. He underwent a right occipital and suboccipital craniotomy with complete excision of the right transverse sinus. The patient is stable and neurologically intact for 4 years of follow-up period.

Case 3: A 54-year-old male presented with headache and loss of vision in the left eye and diminution of vision in the right eye that necessitated urgent surgery. He was found to have 7.2, 7.3, and 8.0 cm in all three dimensions originated from the inferior sagittal sinus. The patient underwent right frontal orbitozygomatic approach followed by second stage surgery of combined endoscopic endonasal and open craniotomy through the same previous approach. The surgery was followed by 50.4 Gy of radiation. The patient improved vision on the right eye and is blind on the left, stable for 3 years of follow-up period with no recurrence.

Case 4: A 60-year-old male presented to the emergency department with headache and syncope; the patient was found to have a mass in the Pineal region originating from the straight sinus causing hydrocephalus. He underwent emergent V-P shunting. He underwent two-staged supracerebellar infratentorial followed by interhemispheric approach. The patient is stable for 3 months of follow-up period. The patient received 60 Gy in 33 fractions of radiation.

All pathological examination revealed STAT6 positive staining. None of the patients had distant metastasis.

Conclusion: Solitary fibrous tumors are rare diseases that seem to be related to a venous sinus as origin. Understanding of these diseases is important as they carry similar radiological appearance with other common pathologies. Some of these tumors are highly vascular. Aggressive approach followed by radiation helped in the control of the disease knowing that 20% carry the risk of distant metastases.