Malignant Pigmented Villonodular Synovitis-A Rare Entity.

Area of Science:

• Oncology
• Pathology
• Surgical Oncology

Background:

• Malignant pigmented villonodular synovitis (PVNS), also known as malignant giant cell tumor of the tendon sheath (MGCTTS), is a rare and controversial neoplasm.
• While typically a localized tumor, rare cases exhibit metastatic potential, with fewer than 20 documented instances in medical literature.

Observation:

• A 65-year-old female patient with a history of recurrent PVNS developed inguinal swelling.
• Imaging revealed extensive lymphadenopathy in the iliac region, indicative of metastatic disease.
• Histopathological and immunohistochemical analysis confirmed metastatic PVNS.

Findings:

• The patient presented with metastatic PVNS to inguinal and pelvic lymph nodes, a highly unusual presentation.
• Despite initially bland cytologic features, the lesion demonstrated aggressive behavior with local recurrence and distant metastasis.

Implications:

• High clinical suspicion is essential for diagnosing aggressive PVNS, even with unremarkable cytology.
• Prompt diagnosis and wide surgical excision with clear margins are critical for potential limb salvage and improved outcomes in recurrent GCTTS.