Cytomorphologic panorama of giant cell tumour of tendon sheath

BACKGROUND

Giant Cell Tumour of Tendon Sheath (GCTTS) is a slow growing benign soft tissue tumour arising from synovium of tendon sheath or joint. These tumours occur more frequently in upper limbs, especially hands. In the present study, we aimed to evaluate the cytomorphological spectrum of GCTTS.

METHODS

This retrospective study includes a total of 56 cases of GCTTS diagnosed over a period of 8 years. The clinical and radiological details of these cases were retrieved from the cytopathology records and detailed cytomorphological features were studied and analysed. Histopathological correlation was done in 16/56 cases, where follow-up was available.

RESULTS

The mean age of patients at the time of presentation was 32 years and were predominantly females (68%). The most common site of GCTTS was fingers (76%), followed by foot, wrist and toes. The most consistent finding on cytology was stromal cells (100%) of polygonal, spindle and plasmacytoid morphology with interspersed multinucleated osteoclastic giant cells (100%), followed by binucleated stromal cells (75%), xanthoma cells (61%) and hemosiderin laden macrophages (52%). Presence of proteinaceous fluid background was also observed in 50% of the cases.

CONCLUSION

GCTTS can be diagnosed with certainty on FNAC based on characteristic cytomorphological features in an appropriate clinical and radiological setting. FNAC plays a pivotal role in diagnosing GCTTS and differentiating it from other giant cell rich lesions, thus obviating the need of tissue biopsy for diagnosis, which in turn helps the clinician in timely and adequate management of the patient.

Approach to Fine Needle Aspiration of Giant Cell-rich Tumors of Soft Tissue

Giant cells may be found in a wide variety of reactive and neoplastic soft tissue lesions. Because of their distinct histomorphology, they often stand out in procured samples such as fine needle aspirates. The giant cells themselves may be benign or neoplastic. However, the presence, type, and quantity of giant cells are usually not specific and in some cases can even be misleading when making a diagnosis. The aim of this review is to guide the practicing cytopathologist in narrowing their differential diagnosis when encountering one of these challenging giant cell-rich lesions of the soft tissue.

Case report: Infant with a Fast-growing Soft Tissue Tumor on the Thumb, Revealing a PLAG1-positive Connatal Lipoblastoma

At the age of 4 months, an infant was presented to us with a nodular subcutaneous tumor on the right thumb measuring 2cm, already seen prenatally via ultrasound. An MRI in sedation performed at the age of 4.5 months had no diagnostic specificity. By a biopsy at the age of 5 months malignancy could be excluded. Finally at the age of 16 months the tumor which had meanwhile grown to a monstrous size (5 cm of diameter) could be entirely removed by microsurgical technique maintaining the integrity of all intrinsic structures. The diagnosis of myxoid lipoblastoma was confirmed. According to literature, Lipoblastomas often present as connatal rapid growing soft tissue tumors and are benign. Total removal is essential for avoiding a local recurrence.