Tract Metastasis

A tract metastasis is tumor that grows along the path made by a needle, chest drain, catheter or surgical port, appearing as a lump in the chest wall or skin at that site. Mesothelioma is especially prone to it, and the lump can be painful, but radiation or other treatment can usually ease it.

Origin

Doctors have long noticed tumor growth at procedure sites in mesothelioma. The problem drew more attention as needle biopsies, thoracoscopy and indwelling pleural catheters became routine in the late twentieth century.

Significance in Asbestos Context

Mesothelioma cells can be carried along an instrument's path and grow in the chest wall. Reported rates vary widely with the procedure and the study, and the risk appears higher with larger-bore procedures such as thoracoscopy and surgery than with fine needles. A tract metastasis usually shows up weeks to months later as a firm, sometimes tender lump under the skin at an old biopsy, drain or port site. Radiation can treat it to relieve pain, and surgery is occasionally used. Preventive radiation to procedure tracts was once common but is no longer routinely recommended, after trials found it did not significantly help. Surgeons planning a major operation often remove old port sites. A tract metastasis does not by itself mean a procedure was done badly; it reflects the biology of the disease. In a medical timeline, its appearance documents spread and new pain.

Example Sentence

Three months after his indwelling pleural catheter was placed, he noticed a tender lump at the insertion site, which a biopsy confirmed was a tract metastasis.

Related Terms

Prophylactic Tract Irradiation, Metastasis, Needle Biopsy, Indwelling Pleural Catheter, Thoracoscopy, Pleural Mesothelioma, Disease Progression

Notes

• Report any new lump, swelling or pain at an old biopsy, drain or port site.
• Ask whether radiation could relieve pain from a tract nodule.
• Keep the dates and locations of all chest procedures in one place.