Metastatic Spine Tumors Classification
and Indications for Surgery

It is not surprising that the incidence of spinal metastases is increasing since the spine is the most common site for bone metastases, and there are improvements in medical treatment, as well as an increasingly older population with longer life expectancy.

Spinal metastases are present in as many as 70% of cancer patients, and up to 10% of cancer patients experience metastatic cord compression. Breast, lung, renal, prostate, thyroid, melanoma, myeloma, lymphoma, and colorectal cancer are among the most frequent tumor types that affect the spine.

Survival times have increased with advancements in chemotherapy, radiotherapy, and hormonal therapies, and it is possible that patients’ expectations have also risen. Advancements in surgical techniques, along with technological innovations, have enhanced our doctor’s ability to manage spinal metastases more efficiently.

Surgery can effectively improve mechanical stability, cord compression, and pain. Modern surgery offers superior outcomes compared to radiotherapy alone and can often improve the quality of life after the procedure.

When considering surgery as an option, it is important to keep in mind that the life expectancy of patients with metastatic spinal tumors is typically determined by the stage and type of the tumor. Therefore, the decision to undergo surgery should not negatively impact the patient’s remaining quality of life.

The potential benefits of surgery must be carefully weighed against the complication rate, which can be as high as 20-30%. When the patient is expected to live for more than 3 months, surgery may be considered.

Classification of metastatic spinal tumors

It is essential to perform staging, unless surgery is urgently required, such as in patients experiencing rapid neurological function decline. Some of these classification systems are centered around the patient’s overall tumor burden and functional abilities, whereas others concentrate on the anatomical scope of tumor involvement. This classification is based on three factors:

• Speed at which the primary tumor is growing
• Number of bone metastases
• Presence of visceral metastases

There is a strong correlation between the histology of the primary tumor and the patient’s survival rate, whether they undergo surgery or receive medical treatment. Patients with myeloma, breast, prostate, and thyroid cancers tend to have longer survival times.

Paralysis may be linked to a higher tumor burden or accelerated tumor growth, rather than being directly or distinctly associated with poor survival. Patients whose metastases originate from an unknown primary tumor may have a poorer prognosis compared to those with identifiable tumors.

Anatomical classification systems may be valuable for surgical preparation, but they may be more appropriate for assessing primary tumors than metastases. Typically, to determine the appropriate surgical approach, more information beyond the anatomical location of the tumor is required.

Literature describes a classification system for spinal tumors that often requires prior knowledge of the histology and degree of tumor spread throughout the body. However, this information may not always be available at the time of presentation.

Prognostic Classification And Surgical Planning

Patients who have a highly favorable prognosis should receive extensive excision, while those with moderate scores should receive marginal or intralesional excision and palliative surgery. The group with the poorest prognosis should receive non-surgical supportive care, and no surgical intervention.

Recommendations of the Global Spine Tumor Study Group

The incidence of complications in patients undergoing spinal metastases surgery may reach 25%, with wound infection being the most prevalent complication.

The prognosis of a patient is generally dependent on the extent of metastasis, making surgery beneficial only if it can enhance the patient’s quality of life. As the complexity and extent of a surgical procedure increase, the probability of complications also increases. Hence, there comes a point where a trade-off must be made between the advantages and hazards of the surgery.

Since surgery is mostly palliative for spinal metastases patients, evaluating their overall quality of life may be more significant than physical scores and neurological outcome measures. As a result, the GSTSG recommends employing quality of life assessments for all patients who undergo surgery.

Literature has indicated that surgery for metastases can lead to enhancements in quality of life, with as many as 80% of patients feeling content or very content with the decision to undergo the procedure.

The most significant enhancements are observed in the pain domain, although surgery may also result in improvements in nonspecific symptoms like tiredness, nausea, anxiety, and appetite. For all patients with metastatic disease, the GSTSG employs the Euroqol EQ5D appraisal tool.

If you are interested in knowing more about Metastatic Spine Tumors Classification And Indications For Surgery you have come to the right place!