Osteosarcoma

Introduction:
Osteosarcoma is one of the common types of bone cancer. Though Osteosarcoma can develop in any part of the body, the most common sites are around the knee joint and close to the shoulder. As it develops from osteoblasts (the cells of developing bone), it commonly occurs in children. It is probably caused by genetic factors which changes immature bone cells into cancer cells.

Clinical Presentation:
1. pain and swelling in leg or arm
2. limping gait
3. fracture with trivial trauma
4. backache
5. loss of bladder/ bowel control ( pelvic osteosarcoma)

Signs:
1. swelling just above or below knee joint/ upper arm/ near shoulder
2. painful & limited movements of joint
3. limping gait in case of leg swelling
4. signs of incontinence of bladder/ bowel in case of pelvic or spinal osteosarcoma
5. chest signs in case of metastatic or advanced disease

Diagnosis:
1. X-ray of bone- Lytic lesion with indistinct margins or ossification in the soft tissue with sunburst pattern. Reactive new bone formation is seen as a periosteal elevation, a sign named as a ‘Codman’s angle’ or ‘Codman’s triangle’.
2. MRI of involved bone
3. CT chest
4. Bone scan
5. Tru-cut needle biopsy of tumor

Types
1. Central Osteosarcoma
Conventional
Telangiectatic
Small cell
Low grade
2. Surface Osteosarcoma
Paraosteal
Periosteal
High grade

Treatment:
1. Surgical: Surgical treatments for osteosarcoma consist of either amputation or limb-salvage surgery. Nowadays Limb salvage surgery preferred over amputation. In case of metastatic disease in the lungs, surgery is done to do pulmonary metastatecomy.
2. Chemotherapy: Chemotherapy is given before as well as after surgery. This is called Neoadjuvant chemotherapy and Adjuvant chemotherapy. It removes the microscopic disease in the body.
3. Radiotherapy: The use of radiotherapy is limited in osteosarcoma as it is not very effective. It is used in osteosarcoma that can not be removed surgically.

Prognosis:
In localized disease 60 to 80% survival rate has been reported. Limb osteosarcoma has better prognosis than flat bone osteosarcoma.

Ovarian Carcinomas in Pediatric Age Group

Introduction:
Ovarian Carcinomas are unusual in pediatric age group. It accounts for only 1% of all tumors in girls below the age of 17 years. In the first differential diagnosis of ovarian tumors in adolescent girls, germ cell tumor comes first and carcinomas comes last.

Clinical Presentation:
Abdominal distension
Lower abdominal pain
Weight loss
Malaise

Signs:
Grossly underweight
Lower abdominal mass
ascites

Diagnosis:
Tumor markers- CA 125
CA 125 - CA 125 serology has only 78.1 % sensitivity & 76.8 % specificity but it is useful in identifying recurrent or residual disease.
Ultrasonography- solid, cystic or mixed; arising from, areas of hemorrhage, liver metastasis, retroperitoneal lymph nodes.
CT scan- extent of tumor, exact origin of tumor, better delineation, lymph node status, peritoneal metastasis
Bone scan-for detection of metastasis.

Histopathology:
Serous
Mucinous
Undifferentiated

Treatment:
Surgery: is done to confirm the diagnosis, stage the disease, & achieve tumor clearance in early stages & cytoreduction in late cases.
Chemotherapy: Cisplatin, cyclophosphamide, carboplatin, bleomycin, etoposide, & paclitaxel in various combinations.

Prognosis:
Stage of the disease
Histology

However the prognosis in premenarchal girls appears to be poor with no reported long term survivors.

Germ Cell Tumors

Introduction:
Germ Cell Tumors are the neoplasm arising from primordial germ cells which produces specialized cells in the body like sperm and egg cells. With the recent advances in cisplatin based chemotherapy, the cure rate of germ cell tumors is increased if diagnosed in early stages. It frequently occurs in three modal peaks of life, infancy, 25-40 yrs and around 60 yrs.

Sites:
Testes
Ovaries
Paratesticular area
Abdomen (retroperitoneum)
Mediastinum
Brain
Types:Malignant GCTs: The tumors such as yolk sac tumors, choriocarcinoma, and immature tearatomas encompass this type. The elevated tumor markers, rapid growth signifies malignant transformation.
Benign GCTs: Teratomas are benign tumors. They have characteristic appearance where there are teeth, bone, hair is found inside the tumor.

Symptoms:
Painless scrotal mass
Abdominal mass
Abdominal pain
Breathlessness
Sacral mass

Investigations:
Tumor markers like AFP, β-HCG, LDH
Biopsy
CT Scan/ MRI
Treatment:Surgery: The location of the tumor may influence the need for surgery. When possible, the first choice is usually to try and remove the entire tumor. This can be enough to cure most teratomas and immature teratomas. The coccyx needs to be removed in case of sacrococcygeal teratomas.

Chemotherapy: BEP (Bleomycin, Etoposide & Cisplatin) is the first line chemotherapy for the malignant germ cell tumors. This tumors are very much chemosensitive & the fall in tumor marker gives the idea about the response. If the complete resection is not possible initially then neoadjuvant chemotherapy is advisable.
Radiotherapy: It is indicated as a local therapy when the surgery is not possible.

Prognosis:
The 5-year survival rate is about 95% in germ cell tumors.