An Absolute Commitment

An Absolute Commitment

The Editors:

On September 8, 2008, Northwest Dentistry sat down with Dr. Michael Rohrer, Director of Oral and Maxillofacial Pathology at the University of Minnesota School of Dentistry, to talk about his specialty and the place it occupies in the profession. In lieu of his long and impressive c.v, we asked Dr. R for a quick biographical thumbnail. Said he, "I was, of course, in general practice for two years in the Army during the Vietnam War and three years in private practice. I returned to the University of Michigan for my graduate work in oral pathology. Coming out of Michigan, I taught at the University of Oklahoma for 22 years, including serving in several administrative positions. While there, I was named a Presidential Professor, the first one from the College of Dentistry. In oral pathology, I have been on the American Board of Oral and Maxillofacial Pathology, was its president, and was president of the American Academy of Oral and Maxillofacial Pathology. I have been privileged to help the specialty in that way. I came here in 2000, and am very happy to be back up north!"

The University of Minnesota School of Dentistry's oral pathologists: John Koutlas, left, Director Michael Rohrer, center, and Raj Gopalakrishnan. Behind them is the program's multi-person microscope.

NWD: Let's begin with the basics. What is oral pathology, and how does this specialty fit into the entire dental profession?

Dr. Rohrer: Oral and Maxillofacial Pathology is one of the nine specialties recognized by the American Dental Association. It was started in 1946, founded by seven people. My mentor, Dr. Donald Kerr from Michigan, was one of those seven. Then in 1948, the American Board of Oral Pathology was founded, and the ADA recognized the specialty in 1950. Prior to that it operated as anything from a hobby to a more serious interest. Don Kerr was a periodontist, but as an undergraduate he had worked in the pathology lab and had always kept his interest in pathology. Because there was no oral pathology at the time, he did a general pathology residency. Several of his medical classmates went on to high acclaim in general pathology, which put Don in a league with them, to dentistry's benefit. Bob Gorlin got into oral pathology soon after that. Although he wasn't one of the founders of the specialty, he was one of the first oral pathologists after the specialty was defined and accepted by the ADA. Bob's interest was in advancing the specialty through education. When he talked about this, he'd say that there were these few great "founding fathers" of oral pathology but there were no training programs. Bob Gorlin knew that the specialty would only grow in size and stature if there were a good group of advanced training programs with an excellent academic base. As with the other specialties in dentistry, ours requires extra training. We serve as a referral specialty almost exclusively; patients as a rule do not see us directly. Oral and maxillofacial pathology is the specialtyof dentistry and pathology that deals with the nature, identification, and management of diseases affecting the oral and maxillofacial regions. We investigate the causes, processes and effects of these diseases. The practice of oral and maxillofacial pathology includes research, diagnosis of diseases using clinical, radiographic, microscopic, biochemical or other examinations, and management of patients. Most of the public doesn't know about us at all!

NWD: How much overlap does oral pathology have with medical pathology? How do they complement, or compete with, each other?

Dr. Rohrer: There is a great deal of overlap with medical pathology, which got its modern start in Germany in the 1800s. Rudolf Virchow is considered the "father of pathology". Oral pathology is really more closely aligned with medical pathology than with dentistry. We like to say we are a discipline of pathology and a specialty of dentistry. We are mostly centered in universities, where we do work closely with them because our knowledge complements each other. We usually do not compete for funding, and often jointly participate in research projects. My six-month sabbatical leave starts this January right here at the U over in general pathology.

NWD: What would bring a patient directly to you?

Dr. Rohrer: Either a situation difficult to diagnose or to treat, or managing a difficult clinical situation following diagnosis. There are three of us here - Drs. John Koutlas, Raj Gopalakrishnan, and myself - and one of us sees patients one-half day a week. Most cases are oral/mucosal diseases, many of those autoimmune.

NWD: What is involved in graduate education in oral pathology? Who would be the ideal candidate for your program?

Dr. Rohrer: Graduate education in oral pathology is a minimum three-year program. There are different types of programs: certificate programs that emphasize microscopic and clinical diagnosis, Master's degree programs where there is a research component requiring a Master's thesis, and many people include basic research and get a Ph.D. also. John Koutlas and I have Master's degrees; Raj has a Ph.D. But we are all board certified. Board certification is mandatory for practice, unlike some specialties, because we practice under the rules of the federal government (CLIA). Our lab is licensed and inspected by the federal government, not by the state dental board. In the olden days - which was up to just a few years ago! - board certifications were lifetime, "once and done". We did have a non-mandatory "clinical competency" program. Now virtually all specialty boards are going with a time-limited certificate. Ours is ten years. As for the ideal oral path student, I want the genuinely curious individual. Then, you really have to want to keep up with all the changes, especially in general pathology. Because oral pathology "grew up" as an academic specialty, most of us are in academia. There are very few private practice oral pathologists, and most oral pathologists' private practice is in a faculty practice setting. After time in the Army and private practice, I decided that I wanted to be in academics, and memories of my oral path instructors in dental school led me down the path I took because they had created the greatest excitement in me.

NWD: Tell us about Minnesota's program.

Dr. Rohrer: The Minnesota graduate program ended in the mid-90s, but we are trying to re-establish it. At the U we have an excellent biopsy and clinical patient caseload, excellent faculty, and cooperation with the general pathologists. We will have a top-notch program to offer. There aren't a lot of positions in academics every year open for oral pathologists. However, many more are going into private practice.

NWD: How many oral path graduate programs are there? Where are they located?

Dr. Rohrer: There are 16 in the U.S., two in Canada; very few in the Midwest. In fact, when I was applying for my graduate program, the reputed "top four" were Michigan, Minnesota, Indiana, and Emory University. None of these places even has a program at the moment. Most are on the East Coast. In the middle of the country, Iowa, Ohio State, and Baylor in Dallas have programs. Some programs, like Harvard's, emphasize research; hospital based programs concentrate on microscopic and clinical and diagnosis. Taking the long view, the biggest threat to oral pathology right now is the trend by medical insurance companies to mandate which laboratories must be used for diagnostics. This could mean centralization, even globalization. It's on the radar at least. For the work we do here, the dentists and the oral surgeons are our greatest support.

NWD: How many oral pathologists are there in Minnesota and the upper Midwest? Where are they located?

Dr. Rohrer: In Minnesota it's John Koutlas, Raj Gopalakrishnan, and me right here on the 16th floor. Dr. John Hicks is in Fargo. Then going west there is no one until you reach Seattle or Portland.

NWD: Describe your day. How do you use your training?

Dr. Rohrer: Even on my dullest day I can pause and say, "I must have the most interesting day of any dentist in the world because I've done so many different things." As an academic you think of the tripartite mission of teaching, research, and service. We teach in lectures and seminars, to predoctoral and grad students; we do clinical consultations in the dental school clinics; we consult with dentists, dermatologists, and general pathologists; and we do what no other dentist can do, the microscopic diagnosis. We all do research. Then there are the phone calls and e-mails every day regarding patient diagnosis and treatment. My absolute least enjoyable thing that I ever do is that I occasionally get involved in malpractice cases, and for a number of years I have been a consultant for the oral surgeons' national insurance company. I have done forensic pathology, but not here, and I don't
miss it. I enjoy teaching so much. If someone said I had to pick only one aspect of what I do to do exclusively, it would be hard for me not to choose teaching. When you're in academics, you're on committees - obviously. I am chair of the Promotions and Tenure Committee. It's an opportunity to participate in the governance and improvement of the School of Dentistry and the university.


NWD: What would you like your general practice colleagues to know about your service?

Dr. Rohrer: Anybody can send us biopsies: oral surgeons, endodontists, periodontists, GPs. It depends on a GP's level of comfort whether he or she refers or performs the biopsy in-office. We emphasize that we are as much at the service of dentists as we are of the patients. We're here to help with the dentist's care of his or her patient by supplying the correct diagnosis. We will, of course, deal with genuine clinical challenges here, but we'd rather help dentists manage their patients in their office.

NWD: What are some of the common conditions you are asked to evaluate? How about uncommon?

Dr. Rohrer: Close to half our biopsies are done to make sure the patient doesn't have cancer or pre-cancer. Only about three to four percent (in a year) turn out to be full-blown cancer cases. We see a lot of biopsies of reactive lesions caused by trauma, a lot of intra-bony lesions, cysts, and bone infections. Uncommon? We see metastatic lesions in the jaw or oral soft lesions that are, fortunately, quite rare. Many benign and malignant conditions of the oral cavity and jaws are very uncommon, but we must recognize them when they appear under the microscope. I've seen many strange things clinically because there are still a number of patients who are after drugs and they will do some of the most bizarre things, invent diseases, and even injure themselves. One woman who came here was actually creating blisters in her mouth that didn't correlate with any disease I knew. I don't know how she was doing this, possibly by injecting air or fluid with a syringe. I heard later that she was going to another office, then office to office, seeking drugs, so I felt better!

Then of course there are those moments that defy classification. This one took the cake. A child had a large raised pink mass on the palate, and scared the parents and dentist straight to the Oral Path department at Iowa. Turned out it was half of a little pink rubber ball which had happily suctioned itself to the roof of the mouth. Talk about relief! Seriously though, there's no such thing as a funny biopsy. I make this point to my students this way: No matter how the process is handled, no one driving home after having a biopsy taken is thinking anything other than "Who's going to take care of the kids?" That's why we try to get the results back as soon as possible; within 24 hours in 95% of cases unless there are special circumstances. Very occasionally we will send a biopsy elsewhere to people we consider experts to get a second or supporting opinion. Our biopsy practice is one of the largest in the country. We're on track this year to do about 7,200. We generally receive several cases every week from general pathologists asking for a consultation. And virtually every single day I see something I have never seen before. That keeps it exciting. I tell patients that it's good to have the doctor find them boring, bad to be interesting to a doctor, and worst to be interesting to a doctor at a university!

NWD: How does a dentist, physician, or other medical professional access your service?

Dr. Rohrer: They may call us directly for a free, postage paid biopsy kit. These have a virtually unlimited shelf-life in their offices. Or they may call to refer someone. The number is (612)624-5478. All oral path is charged through medical insurance. All codes are medical insurance procedures. We are Medicare providers, and we do the billing and insurance. It doesn't add another layer back at the dentist's office.

NWD: How about special equipment and other procedures you use in performing your services?

Dr. Rohrer: Typical for biopsies is the standard staining dentists will remember from dental school. We also do special staining, cytology, look at smeared specimens for yeast organisms, and employ immunohistochemistry to look for specialized antigens in tissue to determine where cells are derived
from in difficult diagnostic cases. We will use immunofluorescence to look for antibody reactions against the tissue; look for viruses using in situ hybridization and polymerase chain reaction (PCR); we'll look for genetic-level diseases by looking for gene rearrangements, all to reach the absolute correct diagnosis.

Our regular microscopes allow two of us to look at the specimens at once, but we also have one which
will accommodate five people. The magnification goes from a 25x magnification to 600x. Some diseases are more easily recognized by pattern, some by very high-power cellular changes. Most are a combination. Occasionally we will use electron microscopy, but that has been superceded in great part by immunohistochemistry.

NWD: Do most dentists know about your service, and use it? If not, why not?

Dr. Rohrer: Most do know. I think they may hesitate because they may think, "I should remember this!" They can easily call us - even if they move out of state.

NWD: What additional knowledge should the typical GP have in order to make the most productive referral to you?

Dr. Rohrer: GPs need to occasionally refresh themselves about oral pathology. I tell my students, "You may not see one of these things for ten or 20 years, but your patients and their attorneys will expect you to recognize it!" Take a C.E. course every few years.

NWD: What would you consider an "ideal" referral - one that would provide the most benefit to the patient and the referring doctor?

Dr. Rohrer: The best thing for biopsies is to be brief and clear on the history and description of whatever the situation is; very good to send a picture, including electronically. With a clinical referral, send the patient with a concise history of why he or she is being referred, in writing, please.

NWD: Are there specialties within the specialty such as Dr. Gorlin's interest in syndromes?

Dr. Rohrer: Virtually all oral pathologists are academicians and interested in any area of research you can name. Dr. Gorlin's area was head and neck genetics, and he became the world's expert on that without question. Dr. Koutlas is working with Mayo Clinic on peripheral nerve sheath tumors, and pain research at the VA Medical Center using magnetoencephalography. My research relates to bone: grafts, and dental implants. Dr.Gopalakrishnan is interested in bone at the very basic genetic level. There are no true, named sub-specialties, however. I feel that the academic life is truly exciting every day. I get to teach, to watch the students develop. I get to travel all over the world. I came back to the academic life because I missed it.

NWD: How do you advertise the availability of your service to potential users?

Dr. Rohrer: We don't advertise to the public. We "advertise" to dentists through our dental school and continuing education teaching.

NWD: What would you like our readers to take away from this conversation?

Dr. Rohrer: Oral pathology is a very small specialty, but a specialty that can very much help the dental profession and the medical profession by specializing in getting to the exact diagnosis as quickly as possible. The best treatment for a patient depends on the best diagnosis. We are a specialty that concentrates on a small area of the body. We all begin as dentists and as clinical practitioners, and we stay connected with the patients and the practitioners. The microscopic diagnosis is the niche we fill in the spectrum of dental care where we can offer the best to the profession and the patient.



An Oral Pathology Sampler

Gingival mass thought to be reactive, traumatically induced.
Histopathology of the gingival mass showed that it was a metastic andenocarcinoma. Immunohistochemistry studies showed that it was most likely from the liver or pancreas. The patient was not aware of any other tumor at the time the oral lesion appeared.
This patient complained of bleeding, sore gums that did not respond to good oral hygiene. A biopsy was performed.
Histopathology of the gingival biopsy showing suprabasilar acantholysis diagnostic for pemphigous vulgaris, a fatal disease if not treated.