Recently I told you about the latest breakthroughs in lung cancer prevention and detection (if you missed that article, click here). Today I want to focus on the exciting advances in the treatment of this terrible disease.
Peter Bach, MD
Published Date: November 5, 2013 Publication: Bottom Line Health
Why? Because although the odds of surviving lung cancer admittedly still aren’t great, these days a lung cancer diagnosis is not an automatic death sentence—even in the case of late-stage cancer. We have many more options for treating the disease than we did just a decade ago…and treatment today is more personalized and precise than ever.
For instance, doctors now can look at the individual characteristics of a tumor, including particular cell patterns and genetic mutations. This information helps them to set treatment plans that are more likely to work—and to avoid recommending treatments with low chances of success. In fact, Peter Bach, MD, an epidemiologist and pulmonologist at Memorial Sloan-Kettering Cancer Center in New York City, told me that he is “extremely enthusiastic” about the progress that’s been made over the past decade.
The problem: Despite the remarkable advances, not all hospitals have the needed tools in their arsenals…and not all doctors understand which patients will benefit from such a personalized approach. That’s why I want you to be in-the-know about the newest ways to beat lung cancer—in case you end up battling the country’s number-one cancer killer.
SECRETS FOUND IN CELL PATTERNS
The term lung cancer actually is misleading because the disease is not just one entity. Rather, there are two major types of lung cancer, each with different risk factors, probable prognoses and treatments. And then even within one of those types, different tumors can have different characteristics that affect how aggressive the cancer may be and which treatment may work.
The majority of lung cancers fall in to the non–small cell category. Adenocarcinoma is the most common non–small cell cancer, accounting for about half of all lung cancers. It’s the type found most often in current and former smokers—and also in people who never smoked.
When adenocarcinoma is detected before it has had a chance to spread, it’s treated surgically. Most of the time, the surgeon performs a lobectomy by removing the entire lobe that has the cancer in it (a pair of lungs has five lobes, three on the right side and two on the left). In some cases, the surgeon does a limited resection, removing just part of the affected lobe.
Tricky: The decision about which procedure to do can be a tough one, according to Prasad Adusumilli, MD, a thoracic surgeon and scientist at Memorial Sloan-Kettering Cancer Center. That’s because the surgeon wants to remove enough lung tissue to prevent a cancer recurrence, but at the same time leave enough tissue to preserve lung function. Until now, there hasn’t been an evidence-based system to guide surgeons, so the size and location of the tumor (for example, how far the tumor is from the edge of the lung) often have been used as criteria in deciding how much to remove.
Breakthrough: Surgeons at Memorial Sloan-Kettering perform about 1,000 of these operations each year. With all the data they have accumulated over the years, Dr. Adusumilli and his research team have developed an algorithm to help surgeons decide which operation is best for patients with adenocarcinoma.
The research that led to the new algorithm was complicated, but basically the researchers performed microscopic examinations of many hundreds of samples of early-stage adenocarcinoma, classifying each according to the proportion of the five major cell patterns (acinar, papillary, lepidic, micropapillary and solid) seen in the tumor. Then they analyzed the follow-up data to determine the chances of cancer recurrence based on the cell pattern and the type of surgery that was done.
Overall, the five-year incidence of cancer recurrence was 21% for patients who had a limited resection and 15% for patients who had a lobectomy. When the specific cell patterns were analyzed, though, it became clear that tumors with a higher percentage of cells showing a micropapillary pattern had a much higher risk for recurrence within the same lobe if patients underwent limited resection.
Bottom line: Doctors can now use this knowledge about cell patterns to opt for the tissue-sparing limited resection procedure in patients whose tumors do not have the aggressive micropapillary pattern…and save the more extensive lobectomy for patients whose cell pattern indicates a high risk for recurrence.
Only a limited number of hospitals have the expertise needed to determine a lung tumor’s cell pattern right on the spot, in the operating room, at the time of the actual surgery. “This requires expert pathological experience and a large volume of tumors for the pathologists to get experienced,” Dr. Adusumilli explained. At hospitals that do not currently have this ability, some patients who get a limited resection may end up needing another operation later if their cancer subsequently is found to have the micropapillary pattern…or, worse, they may have a cancer recurrence.
Hopefully, that will change soon. Dr. Adusumilli and his team of researchers are now trying to develop tools that can more easily determine the cell’s pattern—preferably before surgery—sparing patients the need to go under the knife a second time.
SECRETS FOUND IN GENETIC MUTATIONS
When lung cancer is diagnosed after it has spread to the lymph nodes or beyond, as it is most of the time, treatment involves more than just surgery—it also requires medication. Now, in what Dr. Bach refers to as a “very exciting” development, the particular medications that will work best often can be determined based on specific genetic mutations in the tumors.
How it started: About 10 years ago, during clinical trials for two new lung cancer drugs, doctors observed that some people receiving the drugs gefitinib (Iressa) and erlotinib (Tarceva) had a much better response than others—even though all the patients had advanced adenocarcinoma. This led to the discovery that the patients who responded well had tumors that showed a specific mutation in the epidermal growth factor receptor (EGFR) gene. People with the mutation survived nearly twice as long on the drug regimen as those without it. It turns out that the mutation is present in about 20% of people diagnosed with advanced adenocarcinoma.
A few years later, researchers discovered another mutation on the anaplastic lymphoma kinase (ALK) gene, which is present in 7% of people with adenocarcinoma. A drug that inhibits ALK activity, called crizotinib (Xalkori), is very effective in people who have that particular mutation.
All three of these drugs have been approved, and the required genetic testing is available. Many experts now recommend that all patients with advanced adenocarcinoma have their tumors analyzed for mutations of EGFR and ALK—including patients who have mixed cancer types, even with just a small component of adenocarcinoma. Referring to molecular testing in its entirety, not just for EGFR and ALK, Dr. Bach said, “Now, 60% to 70% of adenocarcinomas have important molecular information that affects therapeutic choices. That’s huge! Lung cancer might be the poster child for this kind of precision, personalized medicine.”
If you are diagnosed with lung cancer: If at all possible, see an oncologist at a hospital associated with a university, Dr. Bach advised. Academic medical centers usually have the technology and expertise to take advantage of these new tests and procedures. If you live too far away to see a doctor there regularly, consider having a consultation with an appropriate expert at such a facility—that person can advise you and your doctor on the best treatment for you.
https://bottomlineinc.com/health/lung-cancer/new-personalized-precision-approach-to-lung-cancer-treatment
