Original tumor can be undetectable

Dear Dr. Gott: In March of last year, my wife had a CT scan of her pelvis because of persisting pain. The scan revealed three fractures in the pelvic bones, secondary to what appeared to be cancer.

Further testing, including a biopsy, confirmed the presence of a malignancy that had metastasized and was likely to have originated in the breast. However, a scrupulous exam, including a mammogram, failed to reveal the location of the primary tumor. Now she is receiving chemotherapy.

However, we are confused about the failure to discover the primary lesion. How can someone suffer from a metastasis without the original growth showing up? We always believed that if a person has a tumor, there is a lump of some kind – or, at least, some suspicious lesion on X-ray studies.

Dear Reader: You are correct that the vast majority of patients with metastatic lesions (cancer that has spread) are diagnosed with a primary (that should itself be treated with surgery, radiation or chemotherapy). However, this doesn’t always hold true. On occasion, the original tumor may be too small to see. Medical testing, although often miraculous, is not 100-percent effective. This is the reason why your wife’s doctors were challenged to find the source of her metastases. Fortunately, in her case the doctors were able to test the metastatic lesion, which I gather was found to be of breast origin. Now she is receiving appropriate therapy.

Pathologists analyze biopsy specimens to determine the presence of cancer and, depending on the type of cells in the tissue, what kind of cancer is present. However, in some instances the metastatic cells are so abnormal that a precise connection to a specific organ or site is virtually impossible.

Consequently, doctors can be hampered by the limitations of medical testing, as well as the problem of tissue identification. We doctors have yet to resolve these issues, but believe me, giant strides have been taken in the past decade. We are getting better at diagnosing ailments such as cancer but we are a long way from perfection.

Dear Dr. Gott: With respect to the reader who swallowed a crown, here’s an interesting story: My friend was having a crown put in when his dentist dropped it. He was told it would pass through. It didn’t.

After about 10 days, he developed a severe cough. An X-ray showed the crown in his lung. He subsequently required surgery to remove it.

I know that this is unusual but it can happen.

Dear Reader: Indeed it can, but an aspiration of foreign material is ordinarily more serious than simply swallowing it. I’m glad your friend successfully came through his ordeal.