Rectal tumor

RT can be administered with curative surgical resection to prevent local recurrence of rectal cancer, before surgery to shrink a rectal tumor and make it operable, or in advanced or metastatic disease to alleviate symptoms. Adjuvant RT, however, does not have a definitive role in colon cancer because recurrences are usually extrapelvic. 

Wakatsuki, K., et al. 2005. Effects of irradiation combined with cw-diamminedichloroplatinum (CDDP) suppository in rabbit VX2 rectal tumors. World J Surg 29 388. 

The anorectal wall is cut 7 mm in length between the two hemostats to prevent colonic obstruction, resulting from rectal tumor progression (Fig. 14.1 A). 

Osteolytic tumors may induce bone destruction either through local invasion, or by a secondary metastatic bone disease. The most frequent types of primary tumors that develop into metastatic bone disease are, in the order of prevalence breast, prostate, thyroid, kidney, and bronchial tumors, whereas esophageal, gastrointestinal and rectal tumors are much less metastatic [11]. Very often, the destruction of bone in a metastatic bone disease leads to hypercalcemia of malignancy, which also responds to BPs. In addition, hematological cancers such as... 

Kim SA, Lim HK, Lee SJ et al (2004) Depiction and local staging of rectal tumors comparison of transrectal US before and after water instillation. Radiology 231 117-122... 

Zagoria RJ, Schlarb CA, Ott DJ et al (1997) Assessment of rectal tumor infiltration utilizing endorectal MR imaging and comparison with endoscopic rectal sonography. J Surg Oncol 64 312-317... 

In the case of definitive treatment approaches in esophageal or rectal cancer, the importance of apoptosis signaling has been documented. Esophageal cancer patients with lack of the proapoptotic Bax molecule have significantly reduced outcome rates (Sturm et al. 2001). Similar findings have been observed for neoadjuvant radiation or radiochemotherapy in patients with rectal tumors with a low expression of Bax (Chang et al. 2005 Nehls et al. 2005). 

Spinelli P, Dal Fante M, Mancini A (1992) Self-expanding metallic stent for endoscopic palliation of rectal tumors a preliminary report. Surg Endosc 6 72-74 Spinelli P, Dal Fante M, Mancini A (1993) Rectal metal stents for palliation of colorectal malignant stenosis. Bildgebung 60 48-50... 

The inflammatory response in UC is propagated by atypical type 2 helper T cells that produce proinflammatory cytokines such as interleukin-1 (IL-1), IL-6, and tumor necrosis factor (TNF).7 As discussed previously, a genetic predisposition to UC may partially explain the development of excessive colonic and rectal inflammation. The finding of positive perinuclear antineutrophil cytoplasmic antibodies (pANCA) in association with the human leukocyte antigen (HLA)-DR2 allele in a large percentage of patients with UC supports this theory.4,12... 

There is currently no definitive role for adjuvant radiation in colon cancer. However, patients who receive surgery for rectal cancer receive radiation therapy to reduce local tumor recurrence. Adjuvant radiation plus chemotherapy is considered standard treatment for patients with stage II or III rectal cancer after the surgical procedure is complete.17 Preoperative radiation may be used to reduce the initial size of rectal cancers in order to make the surgical procedure easier. 

Adjuvant chemotherapy is administered after tumor resection to decrease relapse rates and improve survival in patients with colon cancer by eliminating micrometastatic disease that is undetected on imaging studies. Patients diagnosed with stage I colon or rectal cancer usually are cured by surgical resection, and adjuvant chemotherapy is not indicated in these patients.16 The role of adjuvant... 

Although often treated similarly to colon cancer, there are some important differences in the treatment of rectal cancer compared with colon cancer, especially in the adjuvant setting and the role of radiation. Rectal cancer involves tumors found in distal 15 cm of the large bowel and, as such, is very distinct from colon cancer in that it may recur both locally and dis-tally. The higher incidence of local failure and poorer overall... 

Another unique aspect of rectal cancer is the use of neoadjuvant therapy. Preoperative radiation with or without chemotherapy is given to downstage the tumor prior to surgical resection to improve sphincter preservation by making the surgical procedure easier to perform. The issue of preoperative versus postoperative radiation is a subject of debate and investigation in the United States and will require further data to determine the superiority of one method over the other. 

Abuse of laxatives can lead to a number of health problems, including imbalances in the levels of minerals (electrolytes) in the body, which can lead to dehydration, tremors, weakness, blurry vision, and kidney damage. Laxatives can also change the way nerve endings in the colon work, which can cause the laxative abuser to need more laxatives to have a bowel movement. Other problems with the digestive system that can result from laxative abuse include an increased risk of colon infection (resulting from a loss of the protective cover that lines the colon), rectal pain, gas, and severe constipation. Finally, laxative abuse may lead to both cancerous and noncancerous tumors in the bowel. 

The goal of adjuvant RT for rectal cancer is to decrease local tumor recurrence after surgery, preserve the sphincter, and, with preoperative radiotherapy, improve resectability. 

FU enhances the cytotoxic effects of RT. Compared with surgery alone, the combination of adjuvant 5-FU and RT reduces local and distant tumor recurrences and improves survival in stages II and III rectal cancer. 

The use of 5-FU in combination with radiotherapy has shown improved survival in various malignancies including unresectable pancreatic cancer, resectable pancreatic cancer, Dukes B2 and C rectal cancer, esophageal cancer, and hepatobiliary cancer (Table 2). Similarly, 5-FU with concurrent radiation has also been used for organ preservation in different tumors involving bladder cancer, anal cancer, and laryngeal cancer (Table 3). 

The Mayo Clinic/North Central Cancer Treatment Group (NCCTG) randomized patients with resected rectal cancer and tumor penetration through the rectal wall or with metastatically involved lymph nodes were assigned to postoperative radiation alone (45—... 

Gastrointestinal Tumor Study Group. Prolongation of the disease-free interval in surgically treated rectal carcinoma. NEng JMed 1985 312 1465-1472. 

Chemotherapy and radiation therapy play an important role in the management of colorectal carcinoma. Significant improvements in tumor control and overall survival have been demonstrated with the use of combined-modality therapy in several randomized clinical trials performed over the past 25 yr. This chapter reviews the role of adjuvant chemotherapy and radiation therapy for colon and rectal cancer. Issues surrounding chemoradiation for rectal cancer, including sphincter preservation, total mesorectal excision, local excision, and newer chemotherapy agents, are also discussed. 

---