Hi there,
I'm sorry to hear about your sister. She is lucky to have someone concerned about her to
ask questions on her behalf.
First of all, stage III
rectal cancer is typically treated with both
chemotherapy and radiation. Short-course radiation therapy is commonly used in Europe, but longer duration combination therapy is still preferred in the United States. Initial studies demonstrating its effect were undertaken in the adjuvant setting, in which 5-FU–based chemotherapy with concomitant irradiation proved better than irradiation or surgery alone in preventing both local and distant recurrences. Prolonged infusional 5-FU and twice-daily oral capecitabine are considered equivalent in terms of radiosensitization, although no trial data are available to compare the two. The appropriate sequencing of therapy was assessed in a large German study, in which patients were randomly assigned to receive standard, infusional 5-FU plus irradiation either before or after definitive TME. Preoperative combined modality therapy resulted in a lower rate of local recurrence (6% vs 13% at 5 years), a lower toxicity rate (acute and chronic), and a higher rate of sphincter preservation than did postoperative therapy. Preoperative
chemoradiotherapy has thus become the standard of care for patients with stages II and III rectal cancer.(Source - André T, Boni C, Navarro M, et al.: Improved overall survival with
oxaliplatin,
fluorouracil, and leucovorin as adjuvant treatment in stage II or III
colon cancer in the MOSAIC trial. J Clin Oncol. 27 (19):3109-3116 2009 19451431)
So basically, to answer your question, oral chemotherapy can be used, but IV chemo should also be used in order to maximize her chance of a cure. She will still need surgical excision, but this will be done after her chemotherapy and radiation is complete. If her dialysis access is a catheter, it is possible that they can use the catheter for chemotherapy infusion.
I hope this is helpful. Please let me know if you have any further questions.