Jane,
Thanks for posting a question here at The Doctor's Lounge. Acinar cell
pancreatic cancer is not a common type of cancer of the pancreas. Although acinar cells comprise a significant majority of the exocrine porton of the pancreas, they only account for a small portion (probably around 1%) of cancers that arise from the exocrine pancreas. They can be large when found and can have already metastasized (i.e.- spread beyond the pancreas) when diagnosed. The question of what
chemotherapy to use to treat pancreas cancer depends in part on the stage of the tumor. Could you provide more information about this? Is it widespread and thus no surgery or
radiotherapy are planned? Is surgery a potential treatment option? Are there plans to give
chemotherapy along with
radiotherapy? If
chemotherapy alone is to be used in the setting of advanced, metastatic disease, then there are several choices.
Chemotherapy in general has limitations in how often the cancer responds, how well it responds, and how long it remains under response. There is a difference between shrinking the cancer and just decreasing its activity. Both are important. Shrinking of a cancer is termed a Partial Response. Keeping the cancer stable, yet decreasing its activity and improving any symptoms the cancer may be causing is termed Clinical Benefit. Sometimes cancers of the pancreas do shrink, but on CAT scan images, do not appear to have done so and may appear larger than they were before
chemotherapy was begun. This is due to the development of fibrosis or a so called desmoplastic reaction. CAT scan will show such a response and the remaining cancer as looking the same, hence some confusion in interpreting CAT scans looking at pancreas cancers. Also, the pancreas may be difficult at times to image on routine CAT scans. In the care of my patients with pancreas cancer, I have used various single agent
chemotherapy drugs. Gemcitabine is a commonly used agent, as is 5-Fluyorouracil. Various combinations of drugs have been used. Although it may appear in small studies from single cancer insttitutions that the reponse rates are higher by combining 2 or more drugs instead of just using 1 drug, it is not known if this improved overall survival. Nevertheless, in my practice, if a patient of mine is in good health and has good kidney function, then I use a combination of low-dose
Cisplatin and Irinotecan given each week. Usually this is given for 2-3 weeks in a row, with a 1-week break from
chemotherapy. I keep on repeating it. I have also used single agent gemcitabine, usually given 2-3 weeks in a row, with a 1-week break. Some pancreatic cancers produce certain proteins that can be measured in the blood (e.g.- CA 19-9 or CEA). If these levels are high before treatment, then I do follow them during and even after
chemotherapy.
