Ovarian Cancer and radiotherapy

[sueg]

MY Oncologist has asked me to consider radiotherapy.I am Stage 3c OC diagnosed last year.I had initial surgery,but only my left ovary and omentum was removed,it was impossible to remove the rest,so I had carboplatin/taxol for the next six months,and was left,supposedly with NED.In December a 8cm tumor was found on my remaining ovary and I started on caelyx(Doxil) to try and shrink the tumor and then possibly have surgery.After three cycles the tumor hadn't shrunk,but it hadn't grown either.I've now had 5 treatments of caelyx and my ca125 is rising again.
I'm unable to find anything, anywhere on giving Radiotherapy for Ovarian cancer.What is your opinion on this kind of treatment for this disease please?
Thanks
Sue

[Annekathryn Goodman, M.D.]

Dear Sue,

There are many choices to consider when a cancer has grown back after therapy for ovarian cancer.  The three types of treatment that are available include surgery, chemotherapy, and radiation. If possible, surgery should be strongly considered.

When possible, the ideal strategy is complete surgical removal of a cancer and then chemotherapy. There has been a lot of debate over last 20 years about the usefulness of what is called “secondary surgical cytoreduction”. What that means is that a woman has had surgery for her ovarian cancer and then chemotherapy. Then at some time after initial therapy, the cancer has grown back and further surgery is being considered. Certain guidelines have been set up to help us when facing this question.

Secondary cytoreduction is helpful if the cancer has come back more than six months since completing first line chemotherapy. If a cancer grows back in a shorter time interval, surgery is not a useful therapy. Surgery should be considered if the regrowth of the cancer is isolated. For instance, by CT scan imaging, an isolated pelvic mass is seen, or a nodule in the spleen, or an isolated omental mass. Surgery will not be helpful if there is ascites and signs of multiple areas of cancer recurrence in the abdomen.

As far as chemotherapy, with or without surgery, there are many other drug options. The six-month rule from first treatment to recurrence is used. If a cancer recurs within six months of completion of primary taxol and platinum therapy, the cancer is considered “platinum resistant”. Other drugs are considered such as Doxil, gemcitabine, and topotecan. If more than six months has elapsed, those drugs can also be considered but usually retreatment with a platinum (carboplatin, cisplatin, oxaloplatin) would be considered first. Taxanes (paclitaxel, taxotere) are very appropriate as well.

Radiation is effective as primary therapy after surgery in early ovarian cancer and in advanced ovarian cancer that has been optimally surgically cytoreduced (less than 1 cm of tumor remaining after surgery). It has also been used for recurrences. Radiation is best used in women experiencing an isolated recurrence in the vagina. Radiation has not been a popular option among gynecologic oncologists for recurrences in the abdomen. I found one paper (Gynecologic oncology volume 35 pages 307-313, 1989) that reported that 54 percent of the women who received pelvic radiation had recurrence in the radiation field. 13 percent had bowel obstructions. Another complication of radiation is the reduction of bone marrow reserve. This can affect one’s ability to receive other chemotherapy drugs.

In summary, I would recommend that you ask your oncologist about a consultation with a surgeon- ideally a gynecologic oncologist. There are also many other chemotherapy drugs available. Radiation is a definite option for isolated pelvic disease that cannot be surgically removed but I would tend towards considering other options first.

[sueg]

Thankyou very much.
Sue x