Description
Clinical History
A 57-year old male attends complaining of recurrent pain in his right thigh. On examination there is no palpable abnormality in the thigh. An x-ray of the limb showed bony absorption associated with expansion and periosteal reaction at the proximal right femur. A CT of the limb showed a mass in the proximal right femur. A biopsy was taken of the lesion. Subsequently he had excision of the right upper femur followed by insertion of a prosthesis.
Pathology
The specimen comprises the head, neck and upper third of the shaft of the right femur, sawn longitudinally to display the cut surface. In the medullary cavity of the upper portion of the shaft is an ovoid tumor that is 6.5 cm in maximum diameter. The tumor is not encapsulated and has a hemorrhagic cut surface with pale hyaline and cystic areas. Histologically, this is a low grade chondrosarcoma.
Further Information
Chondrosarcomas are malignant bone tumors that produce cartilage. These are the third most common primary bone malignancy after myeloma and osteosarcoma. Conventional tumors are the most common subtype of chondrosarcoma, making up 90% of cases. Less frequently diagnosed subtypes include clear cell, dedifferentiated and mesenchymal chondrosarcomas.
Some chondrosarcomas arise from pre-existing benign lesions, such as enchondroma or osteochondroma. Common mutations in chondrosarcomas are point mutations in the IDH1 and IDH2 genes as well as silencing of CDKN2A tumor suppressor gene. Chondrosarcomas that occur in multiple osteochondroma syndrome have mutations in the tumor suppressor EXT genes.
Men are twice as likely to develop chondrosarcoma than women. The axial skeleton is more frequently affected than the appendicular skeleton. Around 20% affect the femur. These are largely slow growing tumors. They usually present with painful and gradually enlarging masses. At the time of diagnosis, most are low grade tumors that rarely metastasize. The lungs are the most common site for distant spread. Grade 1 tumors have an almost 90% 5-year survival rate, whereas with grade 3 chondrosarcoma the 5-year survival rate drops to 43%.
CT scan is the optimal radiological investigation for diagnosis with MRI also frequently used. Biopsies may be taken to assist diagnosis. Treatment depends on the grade and the location of the tumor. Complete surgical resection is the standard treatment. Generally, chondrosarcomas do not respond to chemotherapy or radiotherapy given they very slow growing tumors.
Advantages
- Anatomically accurate and identical to real specimen
- No ethical issues - not real human body parts
- Reasonably priced
- Available within a short lead time
- Reproducible, several identical prints can be used as a classroom set
- Can be produced in different sizes to cater for the needs of the teacher
Human Cadavers
- Access to cadavers can be problematic. Many countries cannot access cadavers for cultural and religious reasons
- Cadavers cost a lot money
- High cost for establishing your own plastination suite
- Wet specimens cannot be used in uncertified labs
- Dissection of cadavers is a lot of staff time and that is a cost
- Storage of cadaver material needs special refrigeration etc. which has coast
- If you want another specimen you have to start all over again
Plastinates
- Costs
- Ethical issues
- Timeframe for plastination process
- Many countries do not allow their importation
- One of a kind
Superior 3D print results compared with conventional methods
- Vibrant color offering with 10 million colors
- UV-curable inkjet printing
- High quality 3D printing that can create products that are delicate, extremely precise and incredibly realistic
Clear Support Material
- To avoid breakage of fragile, thin, and delicate arteries, veins or vessels, a clear support material is printed on such spots. This makes the models robust and can be handled by students easily.
