Adenocarcinoma of the Appendix
Adenocarcinoma of the appendix is similar to adenocarcinoma of the colon, and is referred to as "colonic- type" adenocarcinoma of the appendix. This tumor behaves more like colon cancer in that it more commonly metastasizes (spreads) by way of the lymph nodes or bloodstream. Some medical literature states that in 37% of cases the cancer has already spread into the abdominal cavity when it is first discovered.
Most often the first symptom of this cancer is appendicitis. In as many as 50% of cases the tumor perforates (goes through the wall of or "ruptures") the appendix. In other cases it is first discovered as a mass in the lower right side of the abdomen. In some cases the first symptoms are pain in the abdomen or ascites. Only 10 to 20% of cases are discovered unexpectedly when abdominal surgery is being done for another reason. In cases of appendiceal perforation (rupture), the peritoneal cavity (inside of the abdomen) is assumed to be "seeded" with cancer cells, with a high chance of future tumor growth in the abdomen from these cancer "seeds". Metastasis to ovaries in females is also common, and in many cases the first sign of this disease in females is a mass on an ovary.
Treatment for this type of appendix cancer is surgical removal of the appendix (appendectomy) with removal of up to half of the right side of the large colon (right hemicolectomy). There is disagreement in medical literature in regards to recommending preventative surgical removal of the ovaries and fallopian tubes in women to prevent this cancer from occurring there as this is commonly a site to where the cancer spreads.
In some literature intraperitoneal chemotherapy (chemotherapy liquid directly into the abdomen) is recommended in addition to a right hemicolectomy even if there are no other tumors in the abdomen, especially for intermediate and high grade tumors or in cases of perforation (rupture) of the appendix.
cytoreduction surgery and intraoperative hyperthermic chemotherapy are recommended for peritoneal metastasis or peritoneal carcinomatosis (cancerous tumors that have spread into the abdominal cavity)
treatment with systemic chemotherapy (IV Chemotherapy, or chemotherapy given into the veins) that is commonly used to treat colon cancer is also often used for this "colonic-type" appendix cancer. Formal studies have not been done to show if there is an advantage of this chemotherapy for appendix adenocarcinoma since the disease is so rare, but based on the similarities between this type of appendix cancer and colon cancer, it is assumed to be helpful. Some of the IV chemotherapy drugs commonly used are 5-FU, leucovoran, Oxaliplatin and Camptosar (irinotecan). Avastin is also sometimes added. Avastin is not a chemotherapy drug, it is a monoclonal antibody that is anti-angiogenic; meaning it interferes with the growth of new blood vessels which provide nutrients to the tumor. See Systemic (IV) Chemotherapy for Appendiceal Cancer
Disease is more common in men than women with a 3:1 to 2:1 ratio. Occurs most commonly in people 60-70 years old.
Overall survival statistics in some literature are stated as 40-50%, but up to 80% 5 year survival in some cases reported with Dukes Stage A (see American Cancer Society, Inc.-Staging of Colon and Rectal Cancers).
Other medical journal articles suggest survival rates up to 80% are possible even in cases when the cancer has spread into the abdomen if surgery is able to remove all of the cancer in the abdomen (called complete cytoreduction as all of the visible cancer is completely removed) and is combined with heated chemotherapy solution circulated in the abdomen at the time of cytoreduction surgery (this is called intraoperative hyperthermic peritoneal chemotherapy ). Clinical trials are in progress to evaluate the long-term outcome of this therapy combining surgery with chemotherapy into the abdomen.