Does endometrial cancer increase the risk of developing osteosarcoma (bone cancer)?

From the Guidelines

Endometrial cancer does not directly increase the risk of bone cancer. While endometrial cancer can metastasize (spread) to other parts of the body, it typically spreads to the lungs, liver, or lymph nodes rather than to the bones. Bone metastasis from endometrial cancer is relatively uncommon compared to other cancer types like breast, prostate, lung, or kidney cancers, which have a higher tendency to spread to bones. When endometrial cancer does spread to bones, it's considered metastatic endometrial cancer rather than a primary bone cancer. The distinction is important because the cancer cells in the bone would still be endometrial cancer cells, not bone cancer cells.

Key Points to Consider

• The majority of patients diagnosed with endometrial cancer have early-stage disease with a good prognosis after surgery alone 1.
• Risk factors for endometrial carcinomas include increased levels of estrogen, obesity, diabetes, and high-fat diet 1.
• Patients with endometrial cancer should focus on following their recommended treatment plan and regular follow-up appointments to monitor for any spread of the disease.
• If you experience new bone pain while being treated for endometrial cancer, you should report this to your healthcare provider promptly, but understand that bone metastasis is not a common progression of endometrial cancer.

Important Considerations for Management

• The panel suggests that gynecologic oncologists be involved in the primary management of all patients with endometrial cancer 1.
• To further improve outcomes for patients with this disease, physicians need to identify high-risk patients and to tailor treatment appropriately to provide the best long-term survival, including quality of life 1.

From the Research

Endometrial Cancer and Bone Cancer Risk

• The relationship between endometrial cancer and bone cancer risk is complex, with several studies investigating the incidence and prognosis of bone metastases in endometrial cancer patients 2, 3, 4, 5.
• According to a study published in 2013, the incidence of primary bone metastases of endometrial cancer is less than 1% 2.
• Another study published in 2016 found that the survival time in patients without surgical treatment for bone metastasis was 12 months, compared to 42 months in patients who underwent surgical treatment in addition to other therapies 3.

Factors Affecting Prognosis

• Several factors have been identified as affecting the prognosis of endometrial cancer patients with bone metastasis, including histological type of cancer, extra-osseous metastasis, and lack of surgery 3, 4, 5.
• A study published in 2021 found that tumor grade, tumor subtype, liver and brain metastases, local surgery, and systemic chemotherapy were independent risk factors for overall survival and cancer-specific survival in endometrial cancer patients with bone metastasis 4.
• Another study published in 2014 found that isolated bone recurrence and extrapelvic bone metastasis were significant predictors of prolonged survival after the diagnosis of bone metastasis 5.

Bone Density and Endometrial Cancer

• A study published in 2015 compared the bone mineral density (BMD) of postmenopausal women with cervical cancer and endometrial cancer to that of healthy controls, and found that patients with cervical cancer had a lower BMD and were at increased risk of osteoporosis in the lumbar spine 6.
• However, this study did not find any significant differences in basal BMD of the lumbar spine and femur between patients with endometrial cancer and healthy controls 6.

Treatment Approaches

• The optimal treatment approach for endometrial cancer patients with bone metastasis is unclear, but several studies suggest that combination therapies including surgery, radiotherapy, and chemotherapy may be effective 2, 3, 4, 5.
• A study published in 2016 found that surgical treatment in addition to other therapies was associated with improved survival in patients with bone metastasis 3.
• Another study published in 2021 found that local surgery and systemic chemotherapy were independent predictors of overall survival and cancer-specific survival in endometrial cancer patients with bone metastasis 4.