Lasers and Tumors – How targeting can improve outcomes

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One of the tenets of cancer surgery is obtained clear margins around a tumor. In other words, removing enough tissue to make sure you “got it all.” Currently, surgeons rely on a combination of imaging and pathology examinations to determine if the margins of a tumor are clear. A clear margin means that the edge of the tumor can be seen and there is normal tissue beyond the tumor edge. Relying on these detection methods during an operation is time-consuming, costly, and often imprecise. Now, imagine that you could simply look at the tissue and know where the tumor boundaries are. Wouldn’t that be easier, faster, and more reliable? It certainly would be, and researchers Aaron Mohs, Michael Mancini, and Shuming Nie may have found a clever way to achieve this using lasers and injectable dyes to identify the boundaries of tumors.

A 21st Century Wood’s Lamp

The methodology is familiar to many surgeons. The dye injected into the body is known as indocyanine green. Indocyanine green (ICG) is a cyanine dye with low toxicity and side effects. When injected into the vascular system, it binds with plasma proteins and is confined to the vascular system. The dye is cleared by the liver and has a half-life of ~3 minutes. When the dye is exposed to a laser, it emits a fluorescence which can be captured via a camera system and displayed on a monitor. Thus, this dye gives you a way to visualize blood supply in tissues in both presence and intensity. In plastic surgery, I commonly use a system (the SPY imaging system by Lifecell) to identify the blood supply in skin and tissue flaps. This is beneficial when performing reconstruction to know whether the mastectomy skin is going to live or not. Essentially, wherever you see the fluorescence, you have blood supply. The more intense the fluorescence, the greater the blood supply.

So what’s this got to do with Tumors?

The idea of using this technology to identify tumors is a clever adaptation of this technology. Many tumors have a significant increase in vascularity due to angiogenesis and high metabolic rates within the tumor. By using the dye and its corresponding fluorescence, in theory one can identify the borders of the tumor based on this increase in vascularity seen by injecting ICG and using a camera system to detect the fluorescence. In the study by Mohs, Mancini, and Nie, they used a handheld laser with a three-camera capturing system to create a composite image of the tumor in both mice and dogs. They found that in both settings, the dye accumulated preferentially in the tumor tissue over the normal tissue.

The Future is LASERS!

The future of this technology is to improve localization of the dye to the cancerous tissue. Rather than using variations in blood flow and vascularity, a large leap forward would be to identify ways to have tumor cell receptors capture and concentrate the dye. Thus tumor cells could be identified with higher precision and tumor margins accurately delineated. Recently, Mohs was awarded a $1.37 million dollar research grant from the National Institute of Biomedical Imaging and Bioengineering to optimize the system and test in mice. This is a pretty exciting idea and a much better use for lasers than reducing wrinkles!

Cosmetic Surgery: How Old is Too Old?

Have you ever wondered how old is too old to undergo cosmetic surgery? Did you ever tell your mother to stop talking about a facelift because you felt she was too old? Today, people live longer than at any point in human history. And, many people are striving to look better in old age as well. But when it comes to having general anesthesia and cosmetic surgery, is it safe to go under the knife if you are in your 80’s?

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Dr. Yezhelyev, a plastic surgeon at Vanderbilt University, conducted a study which looked at the complication rates from cosmetic surgery between older and younger patients. He also took an additional look at the subset of patients in their 80’s. What Dr. Yezhelyev found were similar rates of complications in older patients and younger patients. This data was presented at the American Society of Plastic Surgeons (ASPS) meeting in Chicago this past October.

The data was accrued from the CosmetAssure database – a company which provides insurance against complications from cosmetic procedures. The timeframe was from May 2008 through May 2013 and included 6700 elderly patients with an average age of 69. The younger patient population used for comparison averaged 39 years old. A separate look at 80-year-olds was also performed.

What was found is a bit surprising. The researchers found that postoperative complications occurred at a rate of 1.94% in the elderly population versus 1.84% in the younger population. This is despite a slightly higher body mass index and diabetes profile in the older age group. Of all the procedures, only abdominoplasty or tummy tuck was found to have a significantly higher rate of complication in the older population (5.4% to 3.9%). It is important to note that facial cosmetic procedures dominated the elderly population’s cosmetic profile (69% vs 12%).

A look at the 80-year old population gives similar results. Overall postoperative complication rates were 2.2%. An increase, but not statistically significant. Again, facial procedures dominated this age group.

So it’s okay for Grandma to have breast implants?

So what does all this data mining tell us? Selection bias is a real phenomenon and that age alone does not predict complication rates. Plastic surgeons do a good job selecting the elderly patients who are healthy enough to undergo cosmetic procedures. This is very important and a good reason why you should go to a Board Certified Plastic Surgeon.

If you performed a cosmetic procedure on 100 random 70 year olds and 100 random 40 year olds, you would likely see a significantly higher rate of complications in the older age group. Medical co-morbidities, previous surgeries, and medications all increase the older we get and all play a role in suitability for surgery. If a patient shows up in my office seeking a necklift, but just had a heart attack, has uncontrolled diabetes, and requires Coumadin (blood thinner) – guess what? I am not going to recommend any surgery. On the other hand – a patient who is 75 and is looking to have an eyelid lift and takes no medications, no history of heart disease, and lives an active/healthy lifestyle is a great candidate for surgery. This is why the consultation is so important. It’s where the benefits are weighed against the risks and the suitability for surgery is assessed. Even after this, elderly patients are required to be cleared for the procedure. This often requires blood work, an ECG, a chest xray and in some cases a stress test. The clearance becomes very important the older a patient gets as it is common to uncover previously undiagnosed conditions which may preclude surgery.

It’s not the years, it’s the mileage.

The bottom line is that this study underscores the importance of patient selection and emphasizes that age alone is not an independent risk factor for cosmetic surgery. The question is not how old you are – the question is how healthy you are.