OK. Now you are diagnosed with pheochromocytoma, carefully prepared before resection, and operated by a great surgeon. Are you out of the loop yet? What shall you do next?
For patients with truly sporadic pheochromocytoma, 90% is the chance that they are cured. The remaining 10% may have recurrence or metastasis in the future. The problem is that the doctors can NOT predict who will be the lucky 90% and who will be the unlucky 10%. Therefore no patients should think that they are absolutely cured and all patients should have follow-up.
My own approach to patients with apparently sporadic pheochromocytoma is to measure plasma metanephrines 1 month after surgical resection to make sure there is no hidden tumor somewhere. Too early measurements can be false positive because I suspect based on my experience that there is some kind of depot of metanephrines in the body that is only depleted in a month. If the metanephrines are normal, I then measure them yearly or whenever they have symptoms suggestive of pheochromocytoma or when an adrenal or other mass is identified incidentally.
If a patient has familial form of pheochromocytoma or a gene mutation is identified, then the patient will have a much higher chance of recurrence or metastasis. Yearly plasma metanephrines are definitely needed. Imaging studies may be indicated depending on which form of familial pheochromocytoma or which gene mutations. Other components of the syndromes need to be screened; patients' family members need to be tested and carriers need to be regularly screened.
Now I have finished the basic topics on pheochromocytoma. I will write more on my personal experience and more interesting topics. If the contents of my blog are mostly based on my own experience and there is not much existing study on the topic, I will clearly state that at the beginning of the post. I welcome colleagues and patients to critique and to suggest. I will also just use "pheo", instead of the full name.
Monday, April 6, 2009
Sunday, April 5, 2009
What to do if pheochromocytoma is diagnosed
This topic is suggested by Dennis.
First of all, making the diagnosis of pheochromocytoma is not a trivial decision. It means more imaging studies and the eventual surgical operation. The patient has to ask two questions: 1) whether the diagnosis is correct, and 2) if the diagnosis is correct, how to proceed with further workups and management.
The experience of the doctor who makes the diagnosis is probably the most critical indicator of whether the diagnosis is correct. The average physicians see few patients with pheochromocytoma in their entire professional life, and they make the diagnosis themselves for even fewer patients. A reasonable question the patient needs to ask the physician is "how many patients with pheochromocytoma have you taken care of?" Most doctors won't be offended by this question. If the doctor has seen fewer than 3 patients, the doctor's experience on pheochromocytoma is too little to make an accurate diagnosis.
The other factor is the doctor's practice environment. Doctors affiliated with an academic center with a large experience on pheochromocytoma have more resources on pheochromocytoma. They know physicians with more experience, they know which radiologists to refer the patients to, and they know which surgeons have the best reputation on pheochromocytoma resecton.
The best doctors on pheochromocytoma are those working in an academic center and doing clinical research on pheochromocytoma. These doctors deal with this disease as part of their career and they have accumulated a large experience on this tumor. They also usually have a program on systemically follow patients after surgical resection.
If the diagnosis is made by an experienced physician, the diagnosis is probably correct. If the diagnosis is made by an inexperienced physician, it may not be necessarily correct, and to have a second opinion from an experienced physician is very prudent. If the patient has the means, it is always a good idea to have a second opinion from another experienced physician even if the diagnosis was already made by an experienced physician, especially when the first physician was not very sure.
To select a surgeon follows the same logic. The best surgeons are those working in an academic center with a large experience on pheochromocytoma and they have operated on more than a few patients with pheochromocytoma. They have seen the tricky perioperative course and work closely with endocrinologists.
As Dennis puts it, a patient should not settle for mere convenience after diagnosed with pheochromocytoma for the first time. Seeking opinions from experienced physicians is very important.
First of all, making the diagnosis of pheochromocytoma is not a trivial decision. It means more imaging studies and the eventual surgical operation. The patient has to ask two questions: 1) whether the diagnosis is correct, and 2) if the diagnosis is correct, how to proceed with further workups and management.
The experience of the doctor who makes the diagnosis is probably the most critical indicator of whether the diagnosis is correct. The average physicians see few patients with pheochromocytoma in their entire professional life, and they make the diagnosis themselves for even fewer patients. A reasonable question the patient needs to ask the physician is "how many patients with pheochromocytoma have you taken care of?" Most doctors won't be offended by this question. If the doctor has seen fewer than 3 patients, the doctor's experience on pheochromocytoma is too little to make an accurate diagnosis.
The other factor is the doctor's practice environment. Doctors affiliated with an academic center with a large experience on pheochromocytoma have more resources on pheochromocytoma. They know physicians with more experience, they know which radiologists to refer the patients to, and they know which surgeons have the best reputation on pheochromocytoma resecton.
The best doctors on pheochromocytoma are those working in an academic center and doing clinical research on pheochromocytoma. These doctors deal with this disease as part of their career and they have accumulated a large experience on this tumor. They also usually have a program on systemically follow patients after surgical resection.
If the diagnosis is made by an experienced physician, the diagnosis is probably correct. If the diagnosis is made by an inexperienced physician, it may not be necessarily correct, and to have a second opinion from an experienced physician is very prudent. If the patient has the means, it is always a good idea to have a second opinion from another experienced physician even if the diagnosis was already made by an experienced physician, especially when the first physician was not very sure.
To select a surgeon follows the same logic. The best surgeons are those working in an academic center with a large experience on pheochromocytoma and they have operated on more than a few patients with pheochromocytoma. They have seen the tricky perioperative course and work closely with endocrinologists.
As Dennis puts it, a patient should not settle for mere convenience after diagnosed with pheochromocytoma for the first time. Seeking opinions from experienced physicians is very important.
Friday, April 3, 2009
Screening for mutations: in whom, and how?
Thank you again, Foxy, for asking an intriguing question on screening for gene mutations that cause pheochromocytoma. As this is a question of general interest, I put it as a new topic.
The chemicals a tumor produces do not tell much about whether the tumor is likely caused by a known mutation. Pheochromocytomas in MENII usually produce epinephrine, while those in VHL usually make norepinephrine. And in general, most pheochromocytomas tend to make norepinephrine, with or without mutations. Extra-adrenal pheochromocytomas (called paragangliomas) in familial paraganglioma (SDH mutations) and in Carney's triad (unknown gene mutations) may not produce catecholamines. Although these patterns of catecholamine secretion exist, they do not help in determining whether a patient should be screened.
Neither does tumor size or patient sex.
Some other clinical parameters do help. 1) Positive family history certainly suggests familial pheochromocytoma. 2) Age. The younger (<50), the more likely a patient has mutations causing pheochromocytoma. 3) Multifocal pheochromocytomas suggest mutations. 4) Signs of genetic syndromes. For example, a patient may already have meduallary thyroid carcinoma. If a patient has any of these, then genetic testing has higher yield.
Should any patient with pheochromocytoma be screened? At last year's International Symposium on Pheochromocytoma (ISP 2008, Cambridge, UK) which I attended, this topic was lively debated and the arguments were divided at the Atlantic Ocean. The European doctors seem to root for testing everyone as the tests are covered by either insurance or research centers. American doctors are more hesitant. No insurance companies in America I know cover genetic testing of pheochromocytoma in a patient without family history. A few American centers do offer testing in a research setting but the patients have to enter a trial of some sort. It can cost a patient thousands of dollars to do all the commercially available tests.
The other issue is which gene(s) to test first. Six (6) genes are known to cause pheochromocytoma: RET, VHL, NF1, SDHB, SDHD, and SDHC. Clinical history provides some help. Bilateral pheos: RET and VHL first. Extra-adrenal pheos: SDHB, SDHD, and VHL first. The hit rate is not very high even with these clinical history-based strategy. Above all, only 30% of patients without family history really have a mutation known to cause pheochromocytoma.
In my own practice, I highly encourage patients with family history to test for mutations. In those without family history, I explain the above and let them decide. Most patients without family history elect not to do genetic testing. They are followed clinically and by tests and imaging. It is unfortunate that genetic testing even in patients with family history are still not covered by insurance in many instances.
The chemicals a tumor produces do not tell much about whether the tumor is likely caused by a known mutation. Pheochromocytomas in MENII usually produce epinephrine, while those in VHL usually make norepinephrine. And in general, most pheochromocytomas tend to make norepinephrine, with or without mutations. Extra-adrenal pheochromocytomas (called paragangliomas) in familial paraganglioma (SDH mutations) and in Carney's triad (unknown gene mutations) may not produce catecholamines. Although these patterns of catecholamine secretion exist, they do not help in determining whether a patient should be screened.
Neither does tumor size or patient sex.
Some other clinical parameters do help. 1) Positive family history certainly suggests familial pheochromocytoma. 2) Age. The younger (<50), the more likely a patient has mutations causing pheochromocytoma. 3) Multifocal pheochromocytomas suggest mutations. 4) Signs of genetic syndromes. For example, a patient may already have meduallary thyroid carcinoma. If a patient has any of these, then genetic testing has higher yield.
Should any patient with pheochromocytoma be screened? At last year's International Symposium on Pheochromocytoma (ISP 2008, Cambridge, UK) which I attended, this topic was lively debated and the arguments were divided at the Atlantic Ocean. The European doctors seem to root for testing everyone as the tests are covered by either insurance or research centers. American doctors are more hesitant. No insurance companies in America I know cover genetic testing of pheochromocytoma in a patient without family history. A few American centers do offer testing in a research setting but the patients have to enter a trial of some sort. It can cost a patient thousands of dollars to do all the commercially available tests.
The other issue is which gene(s) to test first. Six (6) genes are known to cause pheochromocytoma: RET, VHL, NF1, SDHB, SDHD, and SDHC. Clinical history provides some help. Bilateral pheos: RET and VHL first. Extra-adrenal pheos: SDHB, SDHD, and VHL first. The hit rate is not very high even with these clinical history-based strategy. Above all, only 30% of patients without family history really have a mutation known to cause pheochromocytoma.
In my own practice, I highly encourage patients with family history to test for mutations. In those without family history, I explain the above and let them decide. Most patients without family history elect not to do genetic testing. They are followed clinically and by tests and imaging. It is unfortunate that genetic testing even in patients with family history are still not covered by insurance in many instances.
Thursday, April 2, 2009
Suggestions on posting questions
As readers begin to post comments or questions, I note that it may be hard for me to find questions posted under earlier topics. I would like to ask readers to post specific questions on pheochromocytoma under the most recent topic, whatever it is. For example, if you want to ask about interpretation of a specific chromogranin A test, please post the question under this topic simply because it is the most recent one and the question is easier for me to find.
Please still post comments or editorial questions under the specific topic you like to comment on.
I am not really savvy on the technical aspects of blogging. If there are better ways, please let me know.
Thanks.
Dr. Pheo
Please still post comments or editorial questions under the specific topic you like to comment on.
I am not really savvy on the technical aspects of blogging. If there are better ways, please let me know.
Thanks.
Dr. Pheo
Doctor-patient interaction: in response to Foxy's question
Thank you, Foxy, for your comments and question. You have just touched upon an important but overlooked issue in physician-patient relationship. You astutely observe that some doctors can be nervous and defensive when they are seeing patients with rare diseases (including PHEOCHROMOCYTOMA) that they know little about. There is no simple solution to the problem but I can provide some background here so that we can think of creative ways to solve the problem.
Physicians are used to be viewed as knowledgeable experts. They are supposed to help patients, to guide, and to cure. Many physicians also have a large ego as well and enjoy the role of a healer and its associated prestige. When they see a patient who suffers from a disease they know almost nothing, all the pretext of their psyche suddenly does not exist any more. A good number of physicians take this as an opportunity to learn with the patient and acknowledge their ignorance and willingness to learn, while some others will act out and use defensiveness to hide their embarrassment.
Although I don't think patients are to blamed for the problem, patients are indeed also part of the issue. Patients sometimes unknowingly encourage bad physician behaviors. For example, some patients may take arrogance as confidence of a physician. Some patients like black-and-white decisions and take discussion of nuances as indecisiveness of a physician.
At the end of the day, I guess the physician-patient relationship is like any other relationships--you relate with the one you like, and you separate from the one you dislike, and face the consequences.
Finding a good physician should aim at different goals at different disease stages. For definitive diagnosis, you need an expert on pheochromocytoma even though the expert may not be a perfect lady/gentleman. For surgical resection, you need an expert surgeon who has many cases before yours. For follow up, the character of the doctor is more important than knowledge and above all, you may not have a local expert in the first place.
As many of my own patients are from out-of-town, they often ask me how to pick a local doctor to coordinate the care for pheochromocytoma. The advice I give to my own patients is the follows: 1) you trust and like the doctor, 2) the doctor has an open mind on diseases she/he is not familiar with. The specialty of the doctor is not so important.
Let's not even start mentioning the hurdles on choosing physicians placed by HMO, the insurances, and other societal beings.
Dr. Pheo
Physicians are used to be viewed as knowledgeable experts. They are supposed to help patients, to guide, and to cure. Many physicians also have a large ego as well and enjoy the role of a healer and its associated prestige. When they see a patient who suffers from a disease they know almost nothing, all the pretext of their psyche suddenly does not exist any more. A good number of physicians take this as an opportunity to learn with the patient and acknowledge their ignorance and willingness to learn, while some others will act out and use defensiveness to hide their embarrassment.
Although I don't think patients are to blamed for the problem, patients are indeed also part of the issue. Patients sometimes unknowingly encourage bad physician behaviors. For example, some patients may take arrogance as confidence of a physician. Some patients like black-and-white decisions and take discussion of nuances as indecisiveness of a physician.
At the end of the day, I guess the physician-patient relationship is like any other relationships--you relate with the one you like, and you separate from the one you dislike, and face the consequences.
Finding a good physician should aim at different goals at different disease stages. For definitive diagnosis, you need an expert on pheochromocytoma even though the expert may not be a perfect lady/gentleman. For surgical resection, you need an expert surgeon who has many cases before yours. For follow up, the character of the doctor is more important than knowledge and above all, you may not have a local expert in the first place.
As many of my own patients are from out-of-town, they often ask me how to pick a local doctor to coordinate the care for pheochromocytoma. The advice I give to my own patients is the follows: 1) you trust and like the doctor, 2) the doctor has an open mind on diseases she/he is not familiar with. The specialty of the doctor is not so important.
Let's not even start mentioning the hurdles on choosing physicians placed by HMO, the insurances, and other societal beings.
Dr. Pheo
My credential
One reader suggests that I add my credential. Here is a bit about my credential:
I have an MD degree and a PhD degree (in one of the biological sciences). I am board-certified in Internal Medicine and Endocrinology. I practice as a specialist in pheochromocytoma and other neuroendocrine tumors in a large US hospital. I do clinical research in pheochromocytoma.
I never copy and paste any sentences to my blog. In other words, I type every letter in my blog.
The initial blogs are common situations in pheochromocytoma and I say the same words many times to my patients. Therefore I write them down here so that any one interested can read them. I anticipate I will answer more questions than write on general topics in the near future.
The real testament of my credential will be and should be whether my answers to specific questions make sense, help patients and colleagues, and are later confirmed to be correct.
I have an MD degree and a PhD degree (in one of the biological sciences). I am board-certified in Internal Medicine and Endocrinology. I practice as a specialist in pheochromocytoma and other neuroendocrine tumors in a large US hospital. I do clinical research in pheochromocytoma.
I never copy and paste any sentences to my blog. In other words, I type every letter in my blog.
The initial blogs are common situations in pheochromocytoma and I say the same words many times to my patients. Therefore I write them down here so that any one interested can read them. I anticipate I will answer more questions than write on general topics in the near future.
The real testament of my credential will be and should be whether my answers to specific questions make sense, help patients and colleagues, and are later confirmed to be correct.
Wednesday, April 1, 2009
Surgical resection of pheochromocytoma
There are 3 surgical approaches to remove a pheochromocytoma: 1) open adrenalectomy, 2) laparoscopic adrenalectomy, and 3) cortex-preserving partial adrenalectomy.
The open adrenalectomy used to be the only approach but is now usually reserved for large (>10 cm) tumors. The whole adrenal gland along with the tumor is removed.
Laparoscopic adrenalectomy is the main procedure nowadays and is performed for most patients with pheochromocytoma. Again, the whole adrenal gland along with the tumor is removed.
Cortex-preserving partial adrenalectomy only removes the tumor but preserves the adrenal cortex (at least in theory). It is possible only in some patients. It is appealing to young patients with familial pheochromocytoma. These patients will have multiple pheochromocytomas on both adrenal glands and have to take medications for many many years if they have both adrenal glands removed at a young age.
The most important factors for a successful operation are experienced surgeon and anesthesiologist, and of course, careful preoperative preparation. The specific approach a surgeon adopts is less a factor. The surgeon has to be proficient in the specific approach she/he uses.
The open adrenalectomy used to be the only approach but is now usually reserved for large (>10 cm) tumors. The whole adrenal gland along with the tumor is removed.
Laparoscopic adrenalectomy is the main procedure nowadays and is performed for most patients with pheochromocytoma. Again, the whole adrenal gland along with the tumor is removed.
Cortex-preserving partial adrenalectomy only removes the tumor but preserves the adrenal cortex (at least in theory). It is possible only in some patients. It is appealing to young patients with familial pheochromocytoma. These patients will have multiple pheochromocytomas on both adrenal glands and have to take medications for many many years if they have both adrenal glands removed at a young age.
The most important factors for a successful operation are experienced surgeon and anesthesiologist, and of course, careful preoperative preparation. The specific approach a surgeon adopts is less a factor. The surgeon has to be proficient in the specific approach she/he uses.
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