 Good morning everyone, my name is Dr. Devanjal Kapila and I am a secondary radiology resident at Maharashtri Markandeshwar Institute of Medical Sciences and Research and today I will be discussing a rare recurrent case of first metatarsal giant cell tumor occurring after surgical excision. Starting with the introduction, GCT is a benign tumor composed mainly of osteoclast-like giant cells which is locally aggressive and has a tendency for local reoccurrence. The World Health Organization has classified GCT as an aggressive, potentially malignant region. It has higher incidence of multi-sintricity, appears in a younger age and has shorter duration of symptoms average in 6 months or less before a diagnosis is made. Malignant transformation is rare occurring in less than 10% of cases. It usually occurs in young adults. The age group is mainly 20 to 49 years. Region of occurrence is mainly epiphyseo-metatarsal region, nearly 85 to 90% is found in long bones of which 50% occurs around the knee, the distal part of the tumor or the proximal part of tibia. Other frequent sites are distal radius, proximal humerus, fibula, vertebral body and sacrum. In sacrum it occurs usually at the ala. A incidence of 2% is seen in the hand and 1.5% in the foot and GCT of hand and foot seems to represent a different lesion than conventional GCT in the rest of the skeleton. It is classically a subarticular centric-letic lesion with geographic pattern of bone destruction. Poorly defined margins indicate a more aggressive lesion. Trabaculation and cortical expansion are common features and periosteal reaction is seen in about 10 to 15% of cases indicating healing of a pathological fracture. On MRI, T1 weighted images shows an intermediate signal intensity and are usually homogeneous. T2 weighted images shows intermediate to high signal intensity and can be inhomogeneous. The cortical destruction, expansion and trabaculations are well appreciated on CT. So this slide shows a GCT occurring at its most common location and we have a radiograph CT image and the MR for the same. So what you can see over here in the AP radiograph of the left knee is a large lytic lesion seen in the lateral compartment of the distal femur showing geographic pattern of destruction and a small pathological fracture which is much more easily appreciated on the CT image right next to it. We also have coronal T1, T2 and T1 post-gat fat sat images. So you can see there are large intracellic components with hyper intense CT on T1 and T2 images with peripheral irregular hyper intense areas representing hemocytrine and fibrous tissue with surrounding edema in the metaphysis. MRI and FNAC were performed confirming the lesion to be GCT of the first metatarsal of right foot. So jumping on to the imaging findings. So we have a preoperative clinical photo on the left showing a large swelling on the dorsal aspect of the foot medially and on X-ray a large lytic expansile lesion with internal tribulations and proximal subarticular involvement is seen. Marked cortical thinning was noted involving the first metatarsal of right foot. No significant soft tissue swelling was seen on the radiograph. So DDs on the basis of the site of involvement includes ABC, GCT, FNAC was done and SMIR showed numerous multi-nucleated osteoclastic giant cell, more than 15 nuclei distributed unevenly in the cytoplasm. The background on the slide shows hemorrhage features are suggestive of giant cell tumor of the bone. So post excision a fibular graft was placed. The graft is seen fixed proximally to the medial cuneiform and distally to the proximal phallus of the great toe. This is a postoperative radiograph of the right foot showing the fibular graft. So 10 months followed by the surgery and graft play. Patient once again presented with similar complaints with swelling and pain in the right metatarsal region. MRI was performed for the same. So what we can see over here in the APN-lateral radiograph of the foot are there is marked soft tissue swelling along the first metatarsal also showing destruction of the cortices of the fibular graft, axial sag and coronal images of the right foot. A large soft tissue mass is seen in the middle aspect of the foot at the level of the medial cuneiform along the planter, medial and later aspect of the fibular graft. The mass appears hyper intense to muscles on T2 weighted images and shows few cystic and necrotic areas appearing hyper intense on T2 weighted images. The soft tissue is causing geographic lytic destruction of the distal half of the medial cuneiform with associated expansion and cortical. The soft tissue is also seen destructing the cortices of the fibular graft and showing extension into the medullary cavity and there is marks playing of the muscles of the foot on the planter aspect. So FNAC from the mass was done once again and it showed the reoccurrence of the GCT. So in conclusion, follow up case of operated GCT of first metatarsal treated with excision and fibular bone graft and showed reoccurrence of the mass along the bone graft with involvement of medial cuneiform causing lytic destruction. In conclusion, we can see that GCT is a benign tumor which is locally aggressive and has a potential for local reoccurrence. Most common age group is 20 to 49 years. Reoccurrence in this case was less than a year that is 10 months. These are my references.