Monthly Archives: October 2009

CyberKnife to be focus of numerous presentations at the American Society for Radiation Oncology (ASTRO) annual meeting

Source: www.reuters.com
Author: press release

Accuray Incorporated, a global leader in the field of radiosurgery, announced today
that 28 CyberKnife-focused abstracts have been accepted as part of the 51st
Annual Meeting of the American Society for Radiation Oncology (ASTRO), taking
place November 1 – 5 in Chicago, Illinois. This represents a 27 percent
increase in CyberKnife abstracts over last year’s Annual Meeting.

The accepted abstracts, which will be presented as posters or oral
presentations, focus on the use of the CyberKnife® Robotic Radiosurgery System
to treat tumors located throughout the body including the prostate, lung,
brain, spine, liver, pancreas, head and neck.

“The depth and breadth of research presented at this year’s ASTRO meeting is a
testament to the growing clinical acceptance of the CyberKnife System and the
important role it is playing in the treatment of cancer,” said Euan Thomson,
Ph.D., president and CEO of Accuray.

Highlights of the research that will be showcased include seven presentations
focusing on the use of CyberKnife radiosurgery to treat prostate cancer.
CyberKnife prostate procedures from July-September 2009 increased 21 percent
over the same period the previous year, confirming the increasing demand for
this treatment option. To date, CyberKnife radiosurgery has been used to treat
more than 4,000 men with prostate cancer.

Additionally, Accuray will host a number of presentations in the company’s
booth reporting on experience with CyberKnife radiosurgery. Presenters
include Eric Lartigau, M.D., Ph.D., from Centre Oscar Lambret; Xiaodong Wu,
Ph.D., from University of Miami; Donald B. Fuller, M.D., from CyberKnife
Centers of San Diego; Brian T. Collins, M.D., from Georgetown University
Hospital; Joe Y. Chang, M.D., Ph.D., from M. D. Anderson Cancer Center; Debra
Freeman, M.D., from Naples Radiation Oncology; Sonja Dieterich, Ph.D., and
Iris Gibbs, M.D., from Stanford University Hospital; Kim Huang, M.D., from
University of California San Francisco; and Greg Spurlock from US
Radiosurgery.

About the CyberKnife® Robotic Radiosurgery System
The CyberKnife Robotic Radiosurgery System is the world’s only robotic
radiosurgery system designed to treat tumors anywhere in the body
non-invasively. Using continual image guidance technology and computer
controlled robotic mobility, the CyberKnife System automatically tracks,
detects and corrects for tumor and patient movement in real-time throughout
the treatment. This enables the CyberKnife System to deliver high-dose
radiation with pinpoint precision, which minimizes damage to surrounding
healthy tissue and eliminates the need for invasive head or body stabilization
frames.

October, 2009|Oral Cancer News|

Males can get HPV vaccine Gardasil thanks, in part, to Gulfport cancer survivor

Source: St. Petersburg Times

Author: John Barry

David Hastings’ crusade to inoculate boys against a cancer-causing virus that afflicts women — but threatened him, too — has scored a victory. But it’s not quite the one he has been fighting for in the past three years.

A panel of the Centers for Disease Control and Prevention last week allowed a vaccine to be given to boys and young men that is already used to protect girls and young women from human papillomavirus, HPV, which causes cervical cancer.

The panel’s vote followed the Food and Drug Administration’s recent okay of the vaccine for boys as a protection against genital warts.

The vaccine, Gardasil, was approved only for females, ages 9 to 26, in 2006. But research has since linked HPV to many oral cancers in men.

Hastings, who owns the Habana Cafe in Gulfport with his wife, Josefa, testified before the CDC’s Advisory Committee on Immunization Practices. He told them how HPV was found in a deadly carcinoma in his throat in 2006. It took seven weeks of simultaneous chemotherapy and radiation at the H. Lee Moffitt Cancer Center in Tampa to arrest the cancer.

Ever since, he has spread the message that HPV is a threat to men. He urged the CDC panel to recommend routine vaccinations for boys, as it already does for girls.

Hastings and other proponents argued that only 17 percent of girls are completing the series of three doses needed for protection. “We rely on females getting vaccinated to protect males,” he said. “If they don’t, too bad.”

But the panel voted only to allow the vaccinations for boys and men, ages 9 to 26, at their doctors’ discretion. It did not recommend routine use of Gardasil for boys, nor did the panel require doctors to tell parents about it. Insurance companies won’t be obligated to pay for the three doses, which cost about $130 each.

The decision was partly based on the fact that Merck, the vaccine’s maker, had conducted a clinical trial among men only of the vaccine’s effectiveness in treating genital warts, which are not life-threatening.

The committee said it would consider Gardasil’s effectiveness against male cancers in February. Merck plans to present studies next year on Gardasil’s potential as protection against anal cancers among gay men.

“We’re only halfway through the battle,” Hastings said, “but we’re spreading awareness.”

Information from Times wires was used in this report. John Barry can be reached at (727) 892-2258 or jbarry@sptimes.com.



October, 2009|Oral Cancer News|

Pinter opens up about private battle with cancer

Source: Fairfield Citizen
Author: Morgan Thomas

In the 31 years that Redding actress Colleen Zenk Pinter has played Barbara Ryan on As the World Turns, her character has been in a coma following an automobile accident, survived a gunshot wound, been burned to a crisp in an explosion and imprisoned for a crime she did not commit — the stuff of soap writers’ fecund imaginations. But when Barbara was “diagnosed” with oral cancer in 2008, the script was ripped from the real life drama of the actress who plays her and fact-checked with the Oral Cancer Foundation, for which Pinter is now the spokesperson.

Warning the public about this little-known cancer and about a simple 3–5 minute screening your dentist can do has become a mission for Pinter. “The screening is painless,” she said in an interview with the Westport News. “And you don’t have to take your clothes off!”

Oral cancer kills more people each year than cervical, skin or prostate cancer, yet when found early, there is an 80 to 90 percent survival rate.

She took her private health battle public first on the CBS Early Show, filmed a PSA for the Oral Cancer Foundation, a birthday commercial for the American Cancer Society and has spoken before such groups as the 2009 graduating class.

University’s School of Dentistry.

Pinter first noticed that her speech was slurring in December 2005 but her dentist assured the then 52-year-old actress that it was just her teeth shifting. Then in July 2006, she developed a cold sore on her tongue, that would come and go, which she thought was caused by stress.

Finally, in January 2007, the actress went to an oral surgeon, who thought she had a combination of a fungal and bacterial infection. “It was not until he assured me that he had never seen a cancer that looked like that, that cancer even crossed my mind,” she says. “I didn’t know there was such a thing as tongue cancer,” Pinter says. “I had no risk factors: I am not a woman who’s ever smoked or was a heavy drinker. But I’ve since found out that more women are getting this cancer, which is now linked with the same HPV virus that causes cervical cancer.”

Pinter received the news that she had a Stage 2 squamous cell carcinoma on her daughter Georgia’s 14th birthday. “I was in shock. I picked up the birthday cake. We had friends over. We had cake. We had presents. And at 4 the next morning, I got up and went to work.” It was not until that evening that she called her husband, actor Mark Pinter, who was working in California, and her mother with the news. And she got on the Internet (as she had been warned not to do) where she quickly found the Oral Cancer Foundation’s Web site, which she credits with helping save her life. (www.oralcancerfoundation.org)

Pinter credits otolaryngologist, Clarence Sasaki, M.D., and radiologist, Yung H. Son, M.D., at Yale-New Haven, along with the Yale Tumor Board with not only saving her life but her professional life as well. “As an actor, your body, your voice and your face are your tools,” she says.

“I was scheduled for surgery at 6:30 on Tuesday morning with a doctor who was going to do a partial glossectomy (removal of part of the tongue) and a radical neck dissection. I would have been cut from my ear across my throat and had all my lymph nodes removed. It’s very disfiguring and would have affected not just my speech but my taste buds and salivary glands. Many patients, who have no taste buds, stop eating, which creates all kinds of other issues.”

But she went to Yale on Monday for a second opinion and at 6 p.m. the night before her scheduled surgery, the Yale Tumor Board of 40 physicians unanimously agreed that the correct protocol for her cancer was not a radical neck dissection but a partial glossectomy of the right half of her tongue, with reconstruction. By using a flap from the left side of her tongue for reconstruction, her speech and looks would be affected as little as possible. The surgery was followed within six weeks by two brachy-therapies to implant radioactive seeds.

In between surgeries, As the World Turns grouped all of her scenes so that she could shoot on a day that worked around her treatment schedule. “The show was amazing,” she says. “They could have so easily said, ‘This isn’t going to work for us.’ They could have easily re-cast me. But I’m very fortunate. We’re family on that show.”

After the surgeries, viewers started flooding the mailboxes at fan Web sites, wondering what was wrong with Pinter’s speech, speculating that she had had a stroke.

Pinter had already decided to go public with her cancer and went to the show’s executive producer Christopher Goutman in August 2007 to see how he would feel about writing cancer into her character’s storyline. He told her that he had been about to ask her the same thing.

As the World Turns won a 2008 Sentinel Award for “Barbara’s Oral Cancer” from Hollywood, Health, and Society, a division of the USC Annenberg Norman Lear Center. Colleen and Mark Pinter were surprised when the Connecticut Bar Association honored them with the 2008 Distinguished Public Service Award for their charitable work on behalf of various charities, including Bread & Roses, the Mark Twain Library and the Oral Cancer Foundation. This year, Pinter was given the Harry S. Strusser Humanitarian Award for Public Service from the New York University School of Dentistry for her advocacy on behalf of oral cancer awareness and screening.

“When you decide to become a walking, talking ad for a cause, you don’t think about things like awards but when they come along, you realize that someone has heard you. I get so much mail — snailmail, Facebook, e-mail — from people who’ve gotten screened and diagnosed early because they’ve been made aware of this little-known cancer.”

The recurrence rate for oral cancer to return within two years is about 50 percent, and Colleen’s did come back in October 2008. She has since been treated again at Yale, going through another round of radiation therapy this past spring. She is now cancer-free.

As she told Woman’s Day, “The irony is that my cancer could have been found and treated so easily long before it progressed. My doctors say the tumor had been growing for two-and-a-half to four years before we found it. I beg everyone who’s reading this, please, go to your dentist and ask for an oral cancer exam. It takes less than five minutes, and it could save your life.”

On Thursday, Nov. 5, Colleen Zenk Pinter will be the featured speaker at the Women & Company Caring Connections luncheon, sponsored by the American Cancer Society, at the Fairfield County Hunt Club in Westport.

Tickets are $125. For more information, contact Susan Quaranta at (203) 563-0738 or e-mail susan.quaranta@cancer.org.

Biodesix: a new way to inform cancer treatment selection

Source: www.rockyradar.com
Author: staff

“One data point doesn’t tell you very much in most cases,” comments David Brunel, CEO of Biodesix, a medical diagnostics company based in Broomfield, Colorado. This principle guides Biodesix’s approach to developing diagnostics which aim to indentify a patient’s expected response to a particular therapeutic. Biodesix’s technology evaluates multiple biomarkers – identified with a blood sample and analyzed using mass spectrometry – to predict response rather than trying to make a determination based on a single biomarker.

VeriStrat® is the company’s first test, categorizing the expected prognosis of patients with non-small cell lung cancer (NSCLC) who receive treatment with a class of targeted cancer drugs know as epidermal growth factor receptor inhibitors or EGFR-Is. Tarceva (erlotinib) is an EGFR-I commonly used to treat NSCLC patients. VeriStrat classifies patients as either VeriStrat Good or VeriStrat Poor and this information can assist a physician’s decision to pursue treatment with Tarceva or another treatment.

To complete a VeriStrat test, a patient’s blood is drawn and sent to the Biodesix lab in Aurora, Colorado. There the sample is run through a mass spectrometer and the data generated from the mass spectrometer is then processed through a proprietary software algorithm to determine a patient’s VeriStrat classification. The algorithm was developed using samples and subsequent disease response data from patients who had received treatment with an EGFR-I. According to Brunel, “several markers were identified in the group of patients whose cancer is prone to respond to EGFR-I treatment versus those whose cancer is unlikely to respond.” The ability of VeriStrat to identify those NSCLC patients who are likely to survive significantly longer on EGFR-I therapy has been validated in several independent sample sets. In addition, VeriStrat has not shown the ability to separate NSCLC who receive non-EGFR-I treatments such as chemotherapy with statistical significance. And VeriStrat classification is not meaningfully correlated with other factors that might influence survival time such as age, sex, and history of smoking.

The VeriStrat test was launched in May and Biodesix continues to pursue a variety of commercialization activities. The company recently rounded out its management team by adding several industry veterans. Biodesix is currently conducting a prospective randomized clinical trial to enhance the data supporting VeriStrat’s clinical use and targeting opinion leading physicians to gain their support. Biodesix is also working to gain reimbursement for the test from private payers and Medicare. While the cost of VeriStrat is in the thousands of dollars (on par with other personalized medicine diagnostics), Brunel believes the company has focused its efforts in such a way to justify this cost: “It’s hard to make an early-stage diagnostic where you’re screening everyone. But for VeriStrat we are much more selective.” Patients with NSCLC are very sick necessitating efforts to make the best possible treatment choice, and the all the treatment options cost thousands of dollars per month.

While Biodesix remains focused on the commercial success of VeriStrat within NSCLC, Brunel notes many opportunities for expansion as time and resources permit. The company presented data at ASCO (the largest conference for oncologists) related to the use of VeriStrat to identify patients likely for treatment success with Tarceva in head and neck cancer. VeriStrat is also expected to have utility in identifying patient response to EGFR inhibitors other than Tarceva including Erbitux (cetuximab) and Vectibix (panitumumab), which are both used in the treatment of colorectal cancer. Biodesix’s approach of combining mass spectrometry with algorithmic analysis, driven by the scientific efforts of theoretical physicist and CTO Heinrich Röder, will also likely prove effective in identifying response to other types of targeted chemotherapeutics as well as having potential in other conditions including rheumatoid arthritis. Brunel also believes opportunities exist to partner with therapeutic companies to develop companion diagnostics for drugs currently in development.

Biodesix recently brought in a round of financing and has money committed for another round in 2010. Brunel believes this capital gives the company time to ramp its commercial operations and allow runway for it to generate cash flow from VeriStrat. While it is easy to think of newer personalized medicine companies simply as the next type of diagnostic companies, Brunel notes the significant differences in the new breed: “a complex technology, significant risk, and comprehensive clinical trials.” As such, Brunel expects that as Biodesix matures it will “look more like a specialty pharma company than a diagnostics company.”

October, 2009|Oral Cancer News|

Adding chemo helps head, neck cancer patients

Source: HealthDayNews
Author: Staff

TUESDAY, Oct. 27 (HealthDay News) — Combining chemotherapy with radiation treatment for patients with advanced head and neck cancer increases their event-free survival to 2.2 years from just one year with radiotherapy alone, finds a new study.

According to the study authors, “events” include cancer recurrence, new tumors or death.

British researchers looked at the 10-year outcomes of 966 patients with locally advanced head and neck cancer. Those who hadn’t undergone surgery for their cancer were randomly assigned to one of four groups: radiotherapy alone (233 patients); two courses of simultaneous (SIM) chemotherapy given at the same time as radiotherapy (166 patients); two courses of chemotherapy after (subsequent — SUB) completing radiotherapy (160 patients); or both SIM and SUB (154 patients). Patients who’d had surgery were randomly assigned to radiotherapy alone (135 patients) or SIM alone (118 patients).

Overall, non-platinum-based chemotherapy given at the same time as radiotherapy reduced deaths and cancer recurrence in patients who hadn’t undergone surgery, with acceptable toxicity. But patients who’d undergone surgery didn’t benefit from this combined treatment. The researchers also found that chemotherapy given after radiotherapy was ineffective, didn’t improve survival, and doubled the rate of toxicity.

Among patients who didn’t have surgery, median survival time was 2.6 years in the radiotherapy group, and 4.7 years, 2.3 years and 2.7 years, respectively, in patients who received SIM alone, SUB alone, and SIM plus SUB.

Median event-free survival among patients who didn’t have surgery was one year in the radiotherapy group, 2.2 years in patients who received SIM alone, and one year in those who received either SUB alone, or SIM plus SUB.

The findings show the long-term benefit of non-platinum chemotherapy drugs, which are “inexpensive, relatively easy to deliver, and have lower toxicity than platinum therapies … [which] considerably improves the likelihood of completing treatment, essential for improving the chances of a cure,” wrote the U.K. Head and Neck Cancer Group researchers in their report published in the Oct. 27 online edition of The Lancet Oncology.

Combination chemotherapy/radiation treatment should be standard for all advanced head and neck cancer patients for whom surgery isn’t appropriate, they concluded.

More information

The U.S. National Cancer Institute has more about head and neck cancer

October, 2009|Oral Cancer News|

Curry kills gullet cancer cells

Source: www.telegraph.co.uk
Author: Richard Alleyne, Science Correspondent

Scientists based at the Cork Cancer Research Centre in Ireland treated oesophageal cancer cells with curcumin – a chemical found in the curry spice tumeric.

They found that curcumin started to kill cancer cells within 24 hours. The cells also began to digest themselves, according to the research, published in the British Journal of Cancer.

“Scientists have known for a long time that natural compounds have the potential to treat faulty cells that have become cancerous and we suspected that curcumin might have therapeutic value.

“Dr Geraldine O’Sullivan-Coyne, a medical researcher in our lab, had been looking for new ways of killing resistant oesophageal cancer cells.

“She tested curcurmin on resistant cells and found that they started to die using an unexpected system of cell messages.”

Normally, faulty cells die by committing programmed suicide – or apoptosis – which occurs when proteins called caspases are “switched on” in cells.

But these cells showed no evidence of suicide and the addition of a molecule that inhibits caspases and stops this ‘switch being flicked’, made no difference to the number of cells which died.

This suggested that curcumin attacked the cancer cells using an alternative cell signalling system.

Each year around 7,800 people are diagnosed with oesophageal cancer in the UK. Less than 20 per cent of people survive oesophageal cancer beyond five years.

It is the sixth most common cause of cancer death and accounts for around five per cent of all UK cancer deaths.

Dr Lesley Walker, director of cancer information at Cancer Research UK, said: “This is interesting research which opens up the possibility that natural chemicals found in tumeric could be developed into new treatments for oesophageal cancer.

“Rates of oesophageal cancer rates have gone up by more than a half since the 70s and this is thought to be linked to rising rates of obesity, alcohol intake and reflux disease so finding ways to prevent this disease is important too.”

October, 2009|Oral Cancer News|

Head and neck cancer therapy area pipeline report

Source: www.prminds.com
Author: staff

Aarkstore announce a new report “Head and Neck Cancer Therapy Area Pipeline Report” through its vast collection of market research report.

Head and Neck Cancer Therapy Area Pipeline Report contains detailed information on the head and neck cancer drug pipeline. This report provides insight into the pipeline status of head and neck cancer drugs by company and by stage as well as a summary of the latest news and developments in this area.

Scope of the report:
Each Life Science Analytics’ Therapy Area Pipeline Report provides the user with real detail on drug pipelines, by company and by stage, for each specific therapy area. The latest news, by company, also ensures that each report is fresh and up-to-date.

In addition to new developments and disease specific pipeline projects, each report also contains extensive information in tabular format on a company’s full product pipeline and products by phase of development with regard to the therapy area.

Full pipeline details, by stage, are provided and include detailed product descriptions, information on partnering activity plus clinical trial intelligence. Each Therapy Area Pipeline Report also provides detail on the top 20 companies with products in the early stage of development and the top 20 companies with products in the late stage of development. Finally, each report also provides a comparison with other major indications in the disease hub based on Marketed Products vs. Pipeline Products.

Key benefits
• Understand a company’s strategic position by accessing detailed independent intelligence on its product pipeline for specific therapy areas.
• Keep track of your competitors and partners by better understanding their product pipeline.
• Monitor a company’s research effectiveness by determining pipeline depth and number of products in development by clinical phase for specific disease areas.
• Maintain a critical competitive advantage.

October, 2009|Oral Cancer News|

Does the negative node count affect disease-free survival in early-stage oral cavity cancer?

Source: J Oral Maxillofac Surg, November 1, 2009; 67(11): 2473-5
Authors: FL Ampil, G Caldito, GE Ghali, and RG Baluna

Purpose:
We performed a retrospective study to determine whether there is a relationship between disease-free survival and negative lymph node count in patients with resected early-stage oral cavity cancers.

Materials and Methods:
Of the 526 individuals diagnosed with carcinoma of the oral cavity between 1998 and 2005, 52 had undergone primary tumor resection and lymph node dissection of the neck for stage I or II disease. With a mean count of 27 examined negative nodes, these 52 patients were separated into groups with fewer than 27 or > or = 27 uninvolved lymph nodes and compared for disease-free survival.

Results:
The tumor recurred or progressed in 10 patients (19%) during a median follow-up of 27 months. The 2-year disease-free survival rates were 75% and 78% in individuals with fewer than 27 and > or = 27 uninvolved node counts, respectively (P > .78).

Conclusion:
The removal of a greater number of regional, uninvolved cervical lymph nodes does not correlate with disease-free survival in this particular cohort of patients.

Authors’ affiliation:
Division of Therapeutic Radiology, Louisiana State University Health Sciences Center, Shreveport, LA 71130, USA

October, 2009|Oral Cancer News|

Oncolytics Biotech Inc. announces issuance of 33rd U.S. patent

Source: www.benzinga.com/press-releases
Author: press release

Oncolytics Biotech Inc. (“Oncolytics”) today announced that it has been granted its 33rd U.S. Patent, # 7,608,257, entitled “Sensitization of Chemotherapeutic Agent Resistant Neoplastic Cells With a Virus.” The patent claims cover methods of using reovirus in combination with currently approved chemotherapeutic agents to treat patients that are refractory to those chemotherapeutic agents alone.

“This patent supports our expanding clinical program, including our first Phase III study, looking at Reolysin(R) in combination with a range of chemotherapeutic agents,” said Mary Ann Dillahunty, Vice President of Intellectual Property for Oncolytics. “Many of our studies enroll patients that did not previously respond to chemotherapy, including our Phase III study in patients with platinum refractory head and neck cancers.”

About Oncolytics Biotech Inc.
Oncolytics is a Calgary-based biotechnology company focused on the development of oncolytic viruses as potential cancer therapeutics. Oncolytics’ clinical program includes a variety of human trials including a Phase III trial in head and neck cancers using Reolysin(R), its proprietary formulation of the human reovirus.

October, 2009|Oral Cancer News|

Cancers can vanish without treatment, but how?

Source: nytimes.com
Author: Gina Kolata

Call it the arrow of cancer. Like the arrow of time, it was supposed to point in one direction. Cancers grew and worsened.

But as a paper in The Journal of the American Medical Association noted last week, data from more than two decades of screening for breast and prostate cancer call that view into question. Besides finding tumors that would be lethal if left untreated, screening appears to be finding many small tumors that would not be a problem if they were left alone, undiscovered by screening. They were destined to stop growing on their own or shrink, or even, at least in the case of some breast cancers, disappear.

“The old view is that cancer is a linear process,” said Dr. Barnett Kramer, associate director for disease prevention at the National Institutes of Health. “A cell acquired a mutation, and little by little it acquired more and more mutations. Mutations are not supposed to revert spontaneously.”

So, Dr. Kramer said, the image was “an arrow that moved in one direction.” But now, he added, it is becoming increasingly clear that cancers require more than mutations to progress. They need the cooperation of surrounding cells and even, he said, “the whole organism, the person,” whose immune system or hormone levels, for example, can squelch or fuel a tumor.

Cancer, Dr. Kramer said, is a dynamic process.

It was a view that was hard for some cancer doctors and researchers to accept. But some of the skeptics have changed their minds and decided that, contrary as it seems to everything they had thought, cancers can disappear on their own.

“At the end of the day, I’m not sure how certain I am about this, but I do believe it,” said Dr. Robert M. Kaplan, the chairman of the department of health services at the School of Public Health at the University of California, Los Angeles, adding, “The weight of the evidence suggests that there is reason to believe.”

Disappearing tumors are well known in testicular cancer. Dr. Jonathan Epstein at Johns Hopkins says it does not happen often, but it happens.

A young man may have a lump in his testicle, but when doctors remove the organ all they find is a big scar. The tumor that was there is gone. Or, they see a large scar and a tiny tumor because more than 95 percent of the tumor had disappeared on its own by the time the testicle was removed.

Or a young man will show up with a big tumor near his kidney. Doctors realize that it started somewhere else, so they look for its origin. Then they discover a scar in the man’s testicle, the only remnant of the original cancer because no tumor is left.

Testicular cancer is unusual; most others do not disappear. But there is growing evidence that cancers can go backward or stop, and researchers are being forced to reassess their notions of what cancer is and how it develops.

Of course, cancers do not routinely go away, and no one is suggesting that patients avoid treatment because of such occasional occurrences.

“Biologically, it is a rare phenomenon to have an advanced cancer go into remission,” said Dr. Martin Gleave, a professor of urology at the University of British Columbia.

But knowing more about how tumors develop and sometimes reverse course might help doctors decide which tumors can be left alone and which need to be treated, something that is now not known in most cases.

Cancer cells and precancerous cells are so common that nearly everyone by middle age or old age is riddled with them, said Thea Tlsty, a professor of pathology at the University of California, San Francisco. That was discovered in autopsy studies of people who died of other causes, with no idea that they had cancer cells or precancerous cells. They did not have large tumors or symptoms of cancer. “The really interesting question,” Dr. Tlsty said, “is not so much why do we get cancer as why don’t we get cancer?”

The earlier a cell is in its path toward an aggressive cancer, researchers say, the more likely it is to reverse course. So, for example, cells that are early precursors of cervical cancer are likely to revert. One study found that 60 percent of precancerous cervical cells, found with Pap tests, revert to normal within a year; 90 percent revert within three years.

And the dynamic process of cancer development appears to be the reason that screening for breast cancer or prostate cancer finds huge numbers of early cancers without a corresponding decline in late stage cancers.

If every one of those early cancers were destined to turn into an advanced cancer, then the total number of cancers should be the same after screening is introduced, but the increase in early cancers should be balanced by a decrease in advanced cancers.

That has not happened with screening for breast and prostate cancer. So the hypothesis is that many early cancers go nowhere. And, with breast cancer, there is indirect evidence that some actually disappear.

It is harder to document disappearing prostate cancers; researchers say they doubt it happens. Instead, they say, it seems as if many cancers start to grow then stop or grow very slowly, as has been shown in studies like one now being done at Johns Hopkins. When men have small tumors with cells that do not look terribly deranged, doctors at Johns Hopkins offer them an option of “active surveillance.” They can forgo having their prostates removed or destroyed and be followed with biopsies. If their cancer progresses, they can then have their prostates removed.

Almost no one agrees to such a plan. “Most men want it out,” Dr. Epstein said. But, still, the researchers have found about 450 men in the past four or five years who chose active surveillance. By contrast, 1,000 a year have their prostates removed at Johns Hopkins. From following those men who chose not to be treated, the investigators discovered that only about 20 percent to 30 percent of those small tumors progressed. And many that did progress still did not look particularly dangerous, although once the cancers started to grow the men had their prostates removed.

In Canada, researchers are doing a similar study with small kidney cancers, among the few cancers that are reported to regress occasionally, even when far advanced.

That was documented in a study, led by Dr. Gleave that compared an experimental treatment with a placebo in people with kidney cancer that had spread throughout their bodies.

As many as 6 percent who received a placebo had tumors that shrank or remained stable. The same thing happened in those who received the therapy, leading the researchers to conclude that the treatment did not improve outcomes.

The big unknown is the natural history of many small kidney tumors, many of which are early kidney cancers. How often do small tumors progress? Do they ever disappear? Do they all need surgical excision? At what stage do most kidney cancers reach a point of no return?

These days, Dr. Gleave said, more patients are having ultrasound or CT scans for other reasons and learning that there is a small lump on one of their kidneys. In the United States, the accepted practice is to take those tumors out. But, he asks, “Is that always necessary?”

His university is participating in a countrywide study of people with small kidney tumors, asking what happens when those tumors are routinely examined, with scans, to see if they grow. About 80 percent do not change or actually regress over the next three years.

With early detection, he said, “our net has become so fine that we are pulling in small fish as well as big fish.” Now, he said, “we have to identify which small fish we can let go.”

October, 2009|Oral Cancer News|