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Scholarly Works (2 results)

  • Article
  • Peer Reviewed
UC Irvine Previously Published Works (2011)
Background: Colorectal cancer is common worldwide and chemoprevention has the potential of reducing the number of individuals who may suffer and perish from this disease. Methods: A randomized placebo controlled pilot study in colorectal cancer patients was performed using calcium carbonate as the test agent in a multi-institutional oncology study group. Results: Two hundred twenty volunteers were randomized in the study. The primary goals of compliance, accrual, and toxicity monitoring are presented. Presence of multiple adenomas at study entry and subsequent development of metachronous adenomas were recorded and found to be associated with synchronous adenomas. The secondary endpoint of recurrent adenomas indicated lower rates of new adenoma in the volunteers randomized to the calcium group. Conclusion: This pilot study indicates the feasibility of enrolling survivors of colorectal cancer as study volunteers in a colorectal neoplasm chemoprevention clinical trial and oral calcium continues to be a potentially effective drug in reducing colorectal adenomas. © 2011 Elsevier Inc. All rights reserved.
    Cover page: Colorectal Chemoprevention Pilot Study (SWOG-9041), Randomized and Placebo Controlled: The Importance of Multiple Luminal Lesions
    • Article
    • Peer Reviewed
    UC Irvine Previously Published Works (2003)

    Colorectal adenomas are the usual precursors to carcinoma in sporadic and hereditary colorectal cancers (CRC).

    A total of 220 CRC patients (stages 0, I, and II) were randomized prospectively in a double-blind pilot study of calcium chemoprevention by using recurrent colorectal adenomas as a surrogate end point. This trial is still in progress, and we report the preliminary findings on adenoma recurrence rates.

    Synchronous adenomas were present in 60% of patients, and cancer confined in a polyp was present in 23% of patients. The overall cumulative adenoma recurrence rate was 31% (19% in the first year, 29% for 2 years, and 35% for 3 years). The recurrence rates were greater for patients with synchronous adenomas: 38% at 3 years (P =.01). Lower stage was associated with higher adenoma recurrence rates (P =.04). Factors including age, sex, site of primary cancer, and whether the cancer was confined to a polyp were not significantly associated with differences in adenoma recurrence rates.

    The substantial adenoma recurrence rate in patients resected of CRC justifies colonoscopic surveillance on a periodic basis. Patients with higher rates of adenoma recurrences, such as CRC with synchronous adenomas, are ideal subjects for chemoprevention trials.

      Cover page: Adenoma recurrences after resection of colorectal carcinoma: results from the Southwest Oncology Group 9041 calcium chemoprevention pilot study.
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