Patients with resected colorectal cancer are at risk for recurrent cancer and metachronous neoplasms in the colon. This joint update of guidelines by the American Cancer Society (ACS) and US Multi-Society Task Force on Colorectal Cancer addresses only the use of endoscopy in the surveillance of these patients. Patients with endoscopically resected Stage I colorectal cancer, surgically resected Stage II and III cancers, and Stage IV cancer resected for cure (isolated hepatic or pulmonary metastasis) are candidates for endoscopic surveillance. The colorectum should be carefully cleared of synchronous neoplasia in the perioperative period. In nonobstructed colons, colonoscopy should be performed preoperatively. In obstructed colons, double contrast barium enema or computed tomography colonography should be done preoperatively, and colonoscopy should be performed 3 to 6 months after surgery. These steps complete the process of clearing synchronous disease. After clearing for synchronous disease, another colonoscopy should be performed in 1 year to look for metachronous lesions. This recommendation is based on reports of a high incidence of apparently metachronous second cancers in the first 2 years after resection. If the examination at 1 year is normal, then the interval before the next subsequent examination should be 3 years. If that colonoscopy is normal, then the interval before the next subsequent examination should be 5 years. Shorter intervals may be indicated by associated adenoma findings (see Postpolypectomy Surveillance Guideline). Shorter intervals are also indicated if the patient's age, family history, or tumor testing indicate definite or probable hereditary nonpolyposis colorectal cancer. Patients undergoing low anterior resection of rectal cancer generally have higher rates of local cancer recurrence, compared with those with colon cancer. Although effectiveness is not proven, performance of endoscopic ultrasound or flexible sigmoidoscopy at 3-to 6-month intervals for the first 2 years after resection can be considered for the purpose of detecting a surgically curable recurrence of the original rectal cancer. (CA Cancer J Clin 2006;56:160-167.)

Patients undergoing allogeneic bone marrow transplantation who are seropositive for cytomegalovirus are vulnerable to serious cytomegalovirus infection, presumably because of reactivation of latent endogenous virus and severe immunosuppression. We administered intravenous acyclovir from 5 days before to 30 days after allogeneic marrow transplantation for hematologic neoplasms in an effort to prevent cytomegalovirus infection and disease in patients seropositive for cytomegalovirus before transplantation. Eighty-six patients seropositive for both cytomegalovirus and herpes simplex virus before transplantation received acyclovir, whereas 65 patients seropositive only for cytomegalovirus served as controls (acyclovir is the standard prophylactic agent against herpes simplex virus in this setting). The probability that cytomegalovirus infection would develop within the first 100 days after transplantation was 0.70 among acyclovir recipients and 0.87 among control patients at medians of 62 and 40 days after transplantation, respectively (P = 0.0001 by log-rank test). Invasive cytomegalovirus disease developed in 19 acyclovir recipients (22 percent) and 25 control patients (38 percent) (P = 0.008). Survival within the first 100 days after transplantation was better among acyclovir recipients (P = 0.002). Acyclovir prophylaxis was associated with a relative risk of 0.5 or less for the development of cytomegalovirus infection or disease or for death within the first 100 days after transplantation (P less than or equal to 0.04), in proportional-hazards regression analysis. We conclude that prophylaxis with intravenous acyclovir significantly reduced the risk of both cytomegalovirus infection and cytomegalovirus disease in seropositive patients after allogeneic bone marrow transplantation and that it was also associated with significantly improved survival.