A 20-year old male patient presents with pain on movement. X-ray of knee joint shows lytic lesion on the upper end of tibia. What is the likely diagnosis?

Ans, d. Osteoclastoma (Ref: Apley 9/e p202)A 20-year old male patient presents with pain on movement. X-ray of knee joint shows lytic lesion on the upper end of tibia. In the given X-ray, epiphyseal lytic lesion in tibia with a 'soap bubble' appearance is characteristic of osteoclastoma. The tumour always abuts against the joint margin in osteoclastoma."X-ray (Giant-cell Tumour): Radiolucent area situated eccentrically at the end of a long bone bounded by subchondral bone plate. The centre sometimes has a soap-bubble appearance due to ridging of the surrounding bone. Appearance of a 'cystic' lesion in mature bone, extending right up to the subchondral plate, is so characteristic that the diagnosis is seldom in doubt. -- Apley 9/e p202Simple Bone CystAdmantinomaMultiple Myeloma* Fills the medullary cavity but does not expand die boneQ* X-rays: Well-defined radiolucent cyst, often trabeculated & eccentrically placedQ.* In a growing tubular bone it is always situated in the metaphysisQ.* X-ray shows a typical bubblelike defect in the anterior tibia cortex: sometimes there is thickening of the surrounding boneQ* X-rays: The 'classical' lesions are multiple punched-out defects with 'soft' margins (lack of new bone) in the skull, pelvis and proximal femur, a crushed vertebra, or a solitary lytic tumour in a large-bone metaphysisQ.Giant-cell Tumour (Osteoclastoma)Giant-cell tumor represents 5% of all primary bone tumoursLesion of uncertain origin that appears in mature bone, most commonly in distal femur, proximal tibia, proximal humerus & distal radiusQ.Hardly ever seen before closure of the nearby physisQCharacteristically it extends right up to the subarticular bone plateQ.Pathology:Aggressive lesions have a poorly defined edge & extend well into the surrounding boneQ.Histology: Striking feature is an abundance of multinucleated giant cells scattered on a background of stromal cells with little or no visible intercellular tissueQ.Tumour has potential to transform into an osteosarcomaQ.Clinical Features:Patient is usually a young adult who complains of pain at the end of a long bone; sometimes there is slight swellingQ.A history of trauma is not uncommon & pathological fracture occurs in 10-15% of cases.Diagnosis:X-ray Findings of Giant-cell Tumour (Osteoclastoma)Radiolucent area situated eccentrically at the end of a long bone & bounded by subchondral bone plateQ.The centre sometimes has a soap-bubble appearance due to ridging of the surrounding boneQ.Appearance of a 'cystic' lesion in mature bone, extending right up to the subchondral plate, is so characteristic that the diagnosis is seldom in doubtQ.Biopsy is essential. This can be done either as a frozen section before proceeding with operative treatment or (especially if a more extensive operation is contemplated) as a separate procedureQ.Treatment:Well-confined, slow-growing lesions with benign histology can safely be treated by thorough curettage & "stripping" of the cavity, followed by swabbing with hydrogen peroxide or by the application of liquid nitrogen.More aggressive tumours & recurrent lesions: Excision followed by bone grafting