Virtual Microscopy	Choose another topic Cardiovascular Respiratory Renal and Urinary Tract Musculoskeletal Neuro(CNS and PNS) Gastrointestinal Reproductive Endocrine Hematopoiesis and Lymphoid Skin

Case 1:

A 16 year old boy had a compound fracture of the right tibia after an apparent routine fall at a high-school soccer match. Radiology revealed a fracture through a lytic lesion of the proximal tibia with a "ground glass" appearance. During the repair of the fractured tibia, the surgeon curettaged the region of the lytic lesion and filled the defect with cement prior to internal stabilization of the fracture.

Gross Photo: [fibrous dysplasia of the tibia]

Photomicrograph: [fibrous dysplasia, intermediate and high power]

1. What gross feature favors a benign process?
2. What histologic features favor a benign process?
3. Is this disease neoplastic?

Case 2:

A 65 year old woman presented to her physician with severe pelvic pain. Radiology revealed a destructive lesion involving the bones of her pelvis extensively. A biopsy of the lesion was followed by a hemi-pelvectomy.

Gross Photo: [chondrosarcoma of the pelvis]

Photomicrograph: [chondrosarcoma showing permeative pattern]

Photomicrograph: [chondrosarcoma showing hypercellularity]

1. What gross features favor a malignant process?
2. What histologic features favor a malignant process?
3. How does this neoplasm cause harm to the patient?
4. What is tumor grade and how do we grade chondrosarcoma?
5. What is tumor stage and how do we stage chondrosarcoma?

Case 3:

A 16 year old boy complained of right hip pain. Examination revealed an ill defined soft tissue mass in his upper right hip. Radiology showed a lytic lesion involving the proximal right femur with a large soft tissue component.

Gross Photo: [Ewing's sarcoma of the femur]

Photomicrograph: [Ewing's sarcoma]

Photomicrograph: [Ewing's sarcoma - immuno for CD99]

1. What cytologic features suggest a malignant process?
2. How does this neoplasm cause lethality?
3. This neoplasm is characterized by a t(11;22) reciprocal chromosomal translocation fusing the EWS and FLI1 genes, resulting in a chimeric transcription factor. Can you suggest a possible strategy for developing a therapy?

Case 4:

A 50 year old woman had unremitting pain of her right hip. A visit to her physician led to radiologic studies which showed a destructive lesion involving her femur.

Photomicrograph: [metastatic adenocarcinoma of the lung]

Photomicrograph: [keratin immunohistochemistry]

1. In adults, are primary or metastatic neoplasms of bone more common?
2. How would you treat this patient?