Sarcoma
Sarcomas are rare malignancies/cancers that arise from the connective tissues including fatty tissue, muscle, blood vessels, and bone. They can cover a large number of soft tissue cancers (extremity and abdominal) and bone sarcomas (much less common). There are approximately 9,220 sarcomas diagnosed each year. There are some genetic syndromes and chemical/radiation exposure which can be related to sarcomas, but the greater majority have no associated risk factors.
Sarcoma presentation varies by the site. Extremity sarcomas (>50% of soft tissue sarcomas) present with a painless mass 2/3 of the time. Around 30% of abdominal/pelvic sarcomas present with abdominal pain with retroperitoneal sarcoma, indigestion/stomach bleeding with stomach sarcomas, and vaginal bleeding with uterine sarcomas. These sarcomas are typically diagnosed by biopsy of the area. At that point, staging scans (CAT scans, MRI, etc.) are done to define the stage of the sarcoma. They are staged by the grade of the cancer defined by the pathologist under the microscope, tumor size/depth (T stage), lymph node involvement (N stage), and whether the sarcoma has spread distantly (M stage), with the most common site of spread being to the lung.
The stage helps direct the treatment approach for the patient which commonly involves surgery and radiation treatments, and less frequently, chemotherapy. Surgery is the mainstay of therapy for all soft tissue sarcomas of the extremity and trunk. Radical surgery is rarely used. In sarcomas of the extremities, limb sparing surgery is used where a 2 to 3 cm. margin of normal tissue is taken around the sarcoma. Even with this, the risk of local recurrence is 30%+, so adjuvant postoperative radiation treatment for around 6,300 cGy in 35 treatments over 7 weeks is used to significantly reduce the risk of recurrence. This is the standard of care. The course of radiation treatments lasts for 6 to 7 weeks, 5 days a week.