Female, 71 years old.
He was admitted to the hospital due to lumbar pain, flank and left iliac fossa that had been present for 6 months.
It was associated with constipation.
The laboratory showed evidence of infamation.
There were retroperitoneal and mediastinal adenopathies, which led to suspicion of lymphoma.
Surgical biopsy of the retroperitoneal tissue diagnosed a PRF without tumor cells.
Prednisone 30 mg/day and colchicine 1.0 mg/day were prescribed, resulting in rapid pain relief.
She was hospitalized again due to pain reappearance and weight loss.
There was an increase in size of the retroperitoneal mass, involvement of the left psoas and erosion of a vertebra.
Retroperitoneal tissue biopsy revealed undifferentiated cells.
Radiotherapy was performed.
The patient died 10 months after the diagnosis of PKF.
