Welcome back. We're now going to talk about the different types of treatment for individual cancers. As we have learned throughout this course, lung cancer is the most common cancer in men and women. Approximately 220,000 people are diagnosed per year in the United States, and 1.5 million people are diagnosed worldwide. This is a leading cause of cancer death around the world. Notice there's 160,000 deaths per 220,000 diagnoses in the US, and 1.3 million worldwide, when only 200,000 more people are diagnosed every year. This is because most people present with metastatic disease that is not amenable to surgery or radiation, for cure. Because the disease is metastatic at diagnosis, survival is generally measured in months to a few years for lung cancer at the time of diagnosis. Let's look at the potential treatments for lung cancer if it's localized. The whole idea, again, is to get that cancer out, or to treat it with radiation, and surgery is used to remove the cancer, and that means also removing part of the lung. A pneumonectomy is removal of an entire lobe of a lung on the left or the right side, a lobectomy is to just remove a section of the lung, like one-half of one side, and a wedge resection is for very small cancers, where you just remove the cancer and part of a lobe where the cancer is sitting. Radiation is used when surgery is not possible, or if some cancer is left behind after surgery. The treatment of metastatic disease and lung cancer is usually a combination of chemotherapy and targeted therapy. There are many drugs with activity, usually given in a doublet combination, so you'll see Cisplatin plus Taxol, or carboplatin plus Taxotere. Many regimens have been shown to have activity. In addition, you'll see patients treated with a doublet plus Avastin, or a doublet plus Tarceva, if the cancer is noted to be overexpressing EGFR. There are a small percentage of non-small cell lung cancers, about 5% of them, which overexpress the gene ALK. If that is the case, the doublet is also used with Xalkori, which is the medicine that targets the ALK mutation. In 2015, Checkpoint inhibitor blockade was approved for the treatment of metastatic lung cancer, and now immunotherapy is another way to treat metastatic lung cancer. Moving on to breast cancer in previous lectures, we've learned that breast cancer is the most common cancer of women in the United States. Approximately 230,000 cases are diagnosed per year. It's the second leading cause of cancer death in US women, approximately 40,000 deaths per year. Notice here the discrepancy between the number of women diagnosed with breast cancer, 230,000, compared to 40,000 deaths. That's because the majority of women diagnosed with breast cancer in this country have localized disease that is cured by surgery or radiation, with or without some of that adjuvant therapy we talked about. Survival for breast cancer, then, is generally measured in years, even for metastatic disease, because the treatments we have are much more effective than for lung cancer. If a woman has potentially localized disease, the primary treatment is surgery with mastectomy, meaning removing the breast or lumpectomy plus radiation where the surgeon removes their breast cancer lump. Then radiation is given to the rest of the breast to sterilize any microscopic disease. These are considered equally curative for localized breast cancer. For women at high risk of recurrence after surgery or radiation, a combination of drugs are used. In the adjuvant chemotherapy setting, including Adriamycin, the Taxanes, the 5-FU, Syntaxin, and Carboplatin. In addition, if the breast tumor is found to overexpress HER2+, Herceptin is added in the adjuvant setting. If a woman is diagnosed with Metastatic Breast Cancer, many chemotherapy drugs are given in different combinations, including the taxanes and the platinum agents. But women with Metastatic Breast Cancer also benefit from hormonal therapy. Because the breast cancers express estrogen receptor-, and are known as Positive- and/or the progesterone receptor-, and are known as PR positive. Hormone therapy to target the estrogen receptor is used in the adjuvant or metastatic settings to treat breast cancer, alone or in combination with chemotherapy. The most famous drug that blocks estrogen binding is a drug called Tamoxifen, and other newer agents include the Aromatase inhibitors that block estrogen production, including Femara and Arimidex. In addition to chemotherapy and hormone therapy, targeted therapy for breast cancer includes drugs that block HER2+, like Herceptin, and drugs that block mTOR as well as the cyclin kinases. Moving now to prostate cancer, the most common cancer in men, we know that, very similar to breast cancer, approximately 220,000 men will be diagnosed with prostate cancer every year in the United States. It is the second leading cause of cancer death in men after lung cancer, and approximately 27,000 men die in the US yearly. Again, just like we saw in breast cancer, the majority of men diagnosed with prostate cancer have localized disease and are cured with surgery or radiation. The men who have metastatic disease are treated effectively with hormone therapy and chemotherapy, and have a survival measured in years, so looking closer at treatment for potentially localized disease. Radical prostatectomy, where the prostate is removed by the surgeon and external beam radiation therapy are considered to be equally curative for localized disease if a man is believed to have locally advanced prostate cancer, where the disease may have spread just outside of the prostate. External beam radiation plus 2-3 years of hormonal therapy in the medical castration is the therapy of choice for locally advanced disease. Active surveillance, where a physician actively follows a patient without surgery or radiation, can be used for low grade cancers. If prostate cancer has metastasized, hormonal therapy is the first line treatment for prostate cancer. Hormonal therapy is designed to decrease circulating testosterone. The most common hormonal therapies are those drugs that tell the brain to not stimulate testosterone production. Other drugs can be used in combination with these agents that block testosterone binding to the androgen receptor In the cancer cell. Once these drugs are no longer effective, second line treatment includes hormonal agents that induce super castration, which means lowering the testosterone even lower. If those drugs are not effective, the chemotherapy agents Taxotere and Jevtana and Novantrone are used to help people live longer. The bone-targeting radionuclide Xofigo is also used, as well as the cancer vaccine Provenge. For those of you who are interested in learning about prostate cancer in more detail, we have a separate module that you can take. Moving on to colon cancer, this is the third most common cancer in men, and women. With approximately 93,000 people diagnosed per year. It's the third leading cause of cancer death, with approximately 50,000 dying per year in the US. As we have seen, most primary colon cancers are adenocarcinomas. Again, the main treatment for colon cancer is surgery. It allows correct staging, it prevents future blockage of the colon, and prevents bleeding from the cancer. Radiation is rarely used to treat primary colon cancer. If the colon cancer has invaded or spread at the time of surgery, chemotherapy is used in the adjuvant setting. The most common regimens are FOLFOX and CapeOx, which use the drug shown to really target dividing cancer cells. After surgery. If the colon cancer has already metastasized, common chemotherapy regimens are often built off 5-fluorouracil. In addition to chemotherapy, many patients are treated with the targeting agents Either Avastin to target VEGF or Erbitux to target EGFR. Liver Cancer is one of the most common cancers worldwide, especially in Sub-Saharan Africa and SouthEast Asia. So almost, while it is uncommon in the U.S. with only 36,000 cases diagnosed. There are almost 700,00 cases diagnosed around the world. And this is a very lethal disease, because it is not amendable to therapy with surgery for cure. This results in approximately 600,00 deaths worldwide yearly. And approximately 24,000 deaths in the US. Again, survival here is measured in months for metastatic disease. If patients do have potentially localized disease, it turns out that liver transplant is the best option if possible. This is done for small tumors. Meaning one tumor smaller than five centimeters across. Or two to three tumors that are no larger than three centimeters. If liver transplant is not available or not possible, surgery is still attempted. Or in small tumors, tumor ablation. With radiofrequency, ethanol or chemotherapy through the artery feeding the tumor can be used to try and treat the cancer. If the liver cancer is diagnosed in the advanced or metastatic disease state, There is no systemic chemotherapy that has been demonstrated to be effective. And the one therapy that does add months to life, is a targeted therapy with a drug called Sorafenib, which inhibits both the VEGFR receptor and the platelet-derived growth factor receptor. In liver cancer cells. Sometimes in a palliative setting, intra-hepatic arterial therapy is used with the regime FUDR to try and shrink the liver cancer. For those of you who are interested in learning more about liver cancer and liver cancer treatment, There is a subsequent module that you can take. Another common cancer worldwide that is very lethal is stomach cancer approximately 1 million new cases are diagnosed every year Mainly in Southeast Asia, and South and Central America. Of these million cases, about 700,000 mean and women die worldwide yearly. You can see that in the US, the number of new diagnoses is 25,000 with 11,000 deaths. Again, stomach cancer is rarely diagnosed when it is localized and amendable to surgery resulting in metastatic disease that is very hard to treat and survival is measured in months. Surgery is the mainstay treatment. It's often used in conjunction with chemotherapy and/or chemotherapy plus radiation therapy in the neoadjuvant setting. Trying to shrink the cancer so that it can be treated with surgery. If the cancer has already metastasized, chemotherapy with the ECF regimen was the most commonly used regimen, and more recently targeted therapies are being added that target. Either VEGF, or in approximately 20% of stomach cancer, HER2 through the use of Herceptin. This ends our section on the treatment of common cancers. We reviewed the treatments for lung cancer, colon cancer, breast cancer, prostate cancer, liver cancer, and stomach cancer
