Brain cancer is difficult to treat when it starts growing, and a prevalent type, known as a glioma, has a poor five-year survival rate. In a new study published in Proceedings of the National Academy of Sciences, Mayo Clinic researchers report on a new surgical platform used during surgery that informs critical decision-making about tumor treatment within minutes. Time is of the utmost importance when dealing with aggressive malignant tumors.

The platform uses mass spectrometry to identify a key gene mutation in brain cancer, known as isocitrate dehydrogenase (IDH) mutations, in real time. Mass spectrometry is a sensitive technique used to analyze substances in tissue samples, including those altered in cancer.

The study involved more than 240 small tissue biopsies from patients undergoing asleep and awake brain surgery for suspected glioma at Mayo Clinic between 2021 and 2023, and an additional 137 biopsies from an international collaborator. Neurosurgeons collected biopsy samples from the core of the tumor to identify the mutations, as well as from areas around it, to assess if the tumor had spread.

Each tissue sample was placed on a glass slide steps away from the patients during ongoing surgery. The samples were analyzed through the mass spectrometer, which allowed researchers to rapidly assess — within two minutes — whether an IDH mutation was present.

The researchers say that, in addition to enabling real-time diagnosis, the platform allows surgeons to determine a patient's prognosis and perform tumor resection to improve patient outcomes. In the future, the new platform will help surgeons take advantage of the window of opportunity in the operating room to tailor treatment to the molecular features of a tumor, a more personalized approach to medicine.

Researchers hope new therapies developed to target IDH mutations can be delivered in the operating room at the time of surgery.

"The ability to identify this mutation during brain surgery means that one day in the future we may be able to treat patients with this specific mutation locally before they leave the operating room," says the study's senior author, Alfredo Quiñones-Hinojosa, M.D., dean of research and chair of the Department of Neurosurgery at Mayo Clinic in Florida.

"Therefore, we will be able to bring the fight against cancer to the operating room, before chemotherapy and radiation treatments begin, and before the disease has progressed and invaded further." Dr. Quiñones-Hinojosa is also director of the Brain Tumor Stem Cell Research Laboratory.

In the study, researchers were able to diagnose IDH gene mutations with 100% accuracy. They are conducting more research to find other signatures in tumors where the mutation is absent. In addition, they plan to broaden their discoveries to include other types of brain cancers.

This study was supported in part by the National Cancer Institute of the National Institutes of Health under award number R33CA240181. For a full list of authors, funding and disclosures, see the paper.

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Mayo Clinic researchers have developed a new surgical platform that uses mass spectrometry to identify isocitrate dehydrogenase (IDH) mutations in gliomas in real time. This platform allows for rapid, intraoperative decision-making, potentially improving patient outcomes by enabling personalized treatment approaches. The study demonstrated 100% accuracy in diagnosing IDH mutations and suggests future applications for delivering targeted therapies during surgery. Ongoing research aims to identify additional tumor signatures and expand the platform's use to other brain cancers.

Mayo Clinic researchers report on a new surgical platform used during surgery that informs decision-making about tumor treatment within minutes. 

New Research Platform Assesses Brain Cancer Mutations During Surgery

Melanoma, an aggressive form of skin cancer that accounts for 75% of all skin-cancer-related deaths, is often detected later in people with darker skin complexions and the consequences can be devastating, a Mayo Clinic study reveals.

While melanoma may be found less frequently in people with darker complexions than fair ones, this potentially serious form of cancer can strike anyone. The study, which consisted of 492,597 patients with melanoma, suggests that added vigilance in early screening is particularly needed for Black men, whose cancers are often found at later stages, leading to worse outcomes compared to white patients.

"We compared non-Hispanic Black patients to white patients and saw striking differences in how patients presented with the disease," says surgical oncologist Tina Hieken, MD, senior author of the study and a researcher at Mayo Clinic Comprehensive Cancer Center. "We saw more extremity melanoma, and more later-stage disease."

Extremity melanoma refers to skin cancer that can develop on the arms, legs, hands and feet. Various factors, including social risk factors and biological components, could be at play, but further research is needed to help determine why these differences exist.

Revealing differences in sex-based immune response
The research found that Black female patients with melanoma fared better than Black male patients.

Men tended to be older at diagnosis and more likely to have cancer that had spread to their lymph nodes compared to women. This translated to worse survival rates. The researchers learned that Black men with stage 3 melanoma have only a 42% chance of surviving for five years, compared to 71% for Black women.

Most research on melanoma hasn't focused on how race and sex affect outcomes and hasn't looked at the influence of race and ethnicity across all groups. Dr. Hieken says the study highlights the need to understand these differences better, noting that this is the first large study to confirm that sex‐based differences in melanoma outcomes exist within the non-Hispanic Black population.

"When we talk about later-stage melanoma patients who are female versus male in that non-Hispanic Black patient cohort who ended up doing worse, some biological things may be going on here that are interesting," says Dr. Hieken.

One theory centers on variations in immune response.

"Several immune signals suggest that women may respond better to some immunotherapies than males," says Dr. Hieken.

Identifying the need
Researchers note that more studies focused on melanoma in a broader range of people, including more Black participants in clinical trials, is key to bridging this knowledge gap and potentially identifying more effective treatments.

"We want to broaden and deepen our reach to better understand the disease that affects all patients," says Dr. Hieken.

She underscores the role played by the Mayo Clinic Robert D. and Patricia E. Kern Center for the Science of Health Care Delivery in this study.

"What we've done with the Kern Center, with this study and others, is to identify the need," says Dr. Hieken. "We have a rich, integrated, multidisciplinary clinical research practice in melanoma, and we want to address clinical needs and knowledge gaps relevant to our practice."

A wake-up call in the battle against melanoma
Dr. Hieken notes that this study is a wake-up call for everyone battling to diagnose and cure melanoma, regardless of the patient's sex or skin tone.

She emphasizes that healthcare professionals should carefully examine areas like palms, soles and under fingernails, where melanoma might be more challenging to spot on darker skin.

"We can incorporate screening for skin lesions or lesions under the nails into the visit for patients as part of their regular checkups," says Dr. Hieken. "What we want to do is elevate care for our patients."

The Mayo Clinic Robert D. and Patricia E. Kern Center for the Science of Health Care Delivery and Breast and Melanoma Surgical Oncology in the Department of Surgery supported this research. Review the study for a complete list of authors, disclosures and funding.

Melanoma is often detected later in people with darker skin complexions and the consequences can be devastating, a Mayo Clinic study reveals.


Mayo Clinic

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New Research Platform Assesses Brain Cancer Mutations During Surgery

Melanoma In Darker Skin Tones: Race and Sex Play A Role, Mayo Study Finds