The Truth About Melanoma and Skin Cancer: Facts and Common Myths

Often caused by excessive exposure to ultraviolet (UV) rays in sunlight, melanoma accounts for only 4 to 5 percent of skin cancer cases, but is responsible for most skin cancer-related deaths. As with many forms of cancer, melanoma is often misunderstood, and myths persist.

When detected and treated in its earliest stages, however, melanoma is often curable. The key is to avoid overexposure to UV rays – by limiting time outdoors during the peak hours of sunlight and wearing sun-protective clothing and sunscreen – and to be on the lookout for changes in moles and other blemishes that can be an early sign of the disease.

Jennifer Y. Lin, MD, of Dana-Farber Cancer Institute’s Melanoma Treatment Program, sets the record straight on five of the most common myths about melanoma.

Myth 1: A diagnosis of melanoma means that I have months to live.

There are four stages of melanoma — five if you include a form known as melanoma in situ, an early form of the disease that affects only the top layer of skin. Stage 1 melanomas, which are less than one millimeter thick and almost always have not spread beyond their original site, have an excellent prognosis and are generally cured by surgery. The depth of the original melanoma is critical to determining how it will be treated and how people with it are likely to fare. Although more melanomas are being diagnosed, the largest portion are made up of Stage 1 melanomas. Before worrying about the worst outcomes, speak with your doctor about what stage melanoma you have.

Myth 2: There is no difference between SPF 30 and SPF 100 sunscreen.

Although the baseline protection from SPF 30 and SPF 100 is not vastly different, the higher number provides longer coverage. (SPF stands for sun protection factor, or the amount of ultraviolet radiation the skin can absorb without burning while the sunscreen is on.)

If it normally takes you 10 minutes in the sun to burn, an SPF 30 sunscreen protects you for 300 minutes. An SPF 100 should, in theory, provide 1,000 minutes of coverage. If you are sweating and active, the sunscreen can rub off and should therefore be reapplied every two hours. When you are using a high SPF, there is a smaller likelihood of having a “missed spot.” A good way to know that you are applying enough sunscreen is to use the measurement of a shot glass of sunscreen for exposed sites.

Myth 3: If it is a cloudy day, I do not need to wear sunscreen.

About 80 percent of ultraviolet radiation reaches the earth even through clouds. Use a moisturizer with sunscreen daily, especially for areas that have high exposure, such as your face.

Myth 4: If I am low in vitamin D levels, I must get some sun exposure.

Although the skin is the most efficient site of vitamin D production, adequate amounts can be obtained from your diet and from supplements. Vitamin D helps you absorb calcium and build strong bones, so we frequently recommend supplements that include vitamin D and calcium.

Myth 5: If I have dark skin, I can’t burn and won’t get melanoma.

Even people with dark skin can burn if they’re exposed to the sun long enough. Although melanoma is much more rare in individuals of darker skin, it can occur. We recommend that darker-skinned individuals inspect their hands and feet once a month.

Learn more about skin cancer and melanoma from Dana-Farber Cancer Institute.

56 responses to “The Truth About Melanoma and Skin Cancer: Facts and Common Myths

  1. My husband is 45 years old and thinks if he gets skin cancer it will be from overexposure to the sun as child and there is nothing he can do about it now. He has had lots of pre-cancer spots removed from his face as an adult. But he refuses to wear sunscreen because he doesn’t like how it feels.
    Is he right, or am I?

    1. Most skin cancer is secondary to cumulative damage. The more sun protection he can get (especially at such a young age!) the better off he will be. Please continue to encourage him to use sun protection.

  2. my husband died from Melanoma and was going to the melanoma clinic every 6 months for almost 3 years but yet he still died!!! How was it possible that being seen my Melanoma Dr’s his was able to spread to his liver and lungs and within 6 months he was gone!!!!!

    1. It depends on the individual case and stage. 5-6 visits over that length of time may not have been enough. The cancer could have progressed very rapidly in its final stage. My grandmother had a visit where she was at Stage III, and then less than a month later she died of very aggressive Stage IV. It simply moved that fast even though the doctors were doing good work. That’s the nature of melanoma and why it is so deadly.

      My sincere condolences for your loss.

  3. I would like to have seen some mention of tanning beds. Aren’t they dangerous as well? Much worse than sun, minute-for-minute exposure wise?

    1. There is indeed much literature on the harmful effects of tanning bed usage. We are actively pursuing government regulation of tanning bed salons to protect our young patients from excessive exposure to ultraviolet radiation. There has been several articles suggesting that tanning bed use (and in general, UV exposure at a young age) is associated with increased risk of sun exposure

  4. The diagnosis of skin cancer is frightening. However early detection is key to a good outcome. The CDC shows that you have a one percent chance of getting skin cancer. However if you address it early you can lower your chances even more.

  5. my mom died in march of 1994 from a prolonged bout with melanoma. she was only 55 years old. she was first diagnosed in 1986 with a stage 4 mole on her upper thigh.
    she had surgery and went through intensive treatment. she was checked periodilly over the next five years and all looked good. about 3 months after the 5 yrs she was getting ready for bed and felt a lump in her groin. not good. it was back and had gotten into her lymph nodes. it was pure hell for the next 3 yrs and she battled mightly.
    what a horrible way to die. spread to her brain stem and finally to her liver. tumoers covered her upper leg amd groin area like barnicles on a rock. when i see young people going to tanning salons and getting sunburns at the beach i want to tear my hair out. if they only knew the long term affect. maybe i should show them pictures of my mom in her final days. keep up the good work, good luck and god bless.

    1. I am so sorry to hear. I think that is why we are so committed to fighting melanoma because we see too many young people affected.

  6. Why are not more studies made on non melanoma cancer?
    It might not kill but leaves one terribly desfigured.

    1. There is much interest in basal cell carcinoma and squamous cell carcinoma. Please see this Pubmed ID PMID: 19726763 [PubMed – indexed for MEDLINE] for the most recent studies on advanced stage basal cell carcinoma treatments.

      1. Could you direct me on how to find the publication you reference regarding advanced stage BCC treatments?

    1. Hi Rick,

      Thanks for your question about the effects of sunscreen on melanoma. In a recent Australian study, the regular use of sunscreen reduced the risk of all melanomas by 50% and invasive melanomas by 75%. The study also suggested that using sunscreen made people more likely to be aware of the importance of practicing sun safety in general, which likely contributed to the overall decline in melanoma risk. Here’s the research study abstract:

      1. I think the question might be regarding putting sunscreen on existing melanoma. My dermatologist and surgeon both told me the same — that once you have cancer, the only real solution is to stay out of the sun, because sunscreen won’t be effective enough. I also wear sun-protective clothing. Is there research on the efficacy of sunblock versus other methods post-diagnosis?

  7. How can you tell if you have a stage 1 melenoma>?
    Are there symptoms or visible signs?>

    1. In general, we follow the ABCDE’s of melanoma:
      A for asymmetry
      B for border irregularity
      C for color – multiple colors, darker colors than other moles
      D for diameter (greater than 6mm)
      E for evolution which is probably the most important sign, if you have a mole that bleeds, a mole that is growing larger, please see a doctor.

      If at all concerned please see your primary care doctor or your dermatologist.

  8. When researchers say that melanoma is “often” the result of “too much” exposure to ultraviolet light, i would question what is meant by “often” and “too much”. I would be interested to see how many cancers can be correlated w/the effect of too little vitamin D / too little sun exposure.

  9. What is the evidence (literature citations) that wearing sunscreen protects against development of melanoma skin cancer?

  10. I have not seen any data regarding plastic face-shields on motorcycle or snowmobile helmets. It would be helpful to know if the shields protect again the threat of facial melanoma by shielding against UVA and UVB rays.

  11. I would like to hear what is currently known about the contribution of genetic markers for melanoma in combination with environmental exposure to risk factors such as UV.

    1. Unfortunately, genetics play a large role in melanoma risk: if you are fair, with sensitive skin (burns easily) , multiple nevi, you are at baseline at higher risk. Nonetheless, the environmental exposures (most important UV exposure) does enhance your risk. Therefore if one is genetically susceptible, it is especially important to ensure that you are protected from additional UV exposure

  12. I have had surgery twice for Melanoma since November 2011 and once for squamous cell. Should I have any other test to see if it has spread to any other parts of the body. I have my eyes and mouth checked out with no sighs of it spreading.

    1. Hi Richard,

      It’s perfectly normal to be worried about recurrence. There may be other tests or scans you should have, though this may vary depending on your age, risk, and previous diagnoses. The best thing would be to talk with your oncologist to explain your concerns and ask for recommendations.

  13. My husband is currently in a clinic trial for melanoma he has stage 3 – we are very grateful for Dr. Lawrence and the staff at the Yawkee Center for their help and compassion

    1. I am with Dr. Lawrence also at MGH in Boston. Don’t you just love him? He has me doing well with stage IV Mel on the BRAf/MEK human trial. I think the world of him, Dr. Flaherty, and Dr. Chabner. They are life savers with tender hearts and huge brains, going about their work with compassion and humility. My gratitude has no end to it.

  14. My husband was diagnosed with stage 1b malignant melanoma. He had it removed and then more skin along with a sentinel node biopsy. He goes to see the dermatoglogist ever 3 months and the oncologist. All the test he has had done was all clear. But I am still very scared . They took alot of pics of his moles . He has displastic nevi and they are watching 9 of them. He grand dad died of melanoma but he wasn’t taking good care of himself. We have 3 kids and are in our early 30’s . I am so scared that he will get this back. Do most people with stage one get it again? they said he had a 13-15% chance of a new one. But like I said in so scared there are times I just can’t comprehend. Do u have any comforting advice? He wares hats and will put lotion on . I just so afraid to lose him. Please any good news would be great!!!!!!

  15. Hi Jennifer:
    I’m sorry about your husband’s diagnosis. I know that any cancer diagnosis can be a scary time for patients and family members. There’s some good information about melanoma on our web site at
    If you’d like to make an appointment with someone on the melanoma team, please call 877-442-3324. Even if you’ve been diagnosed, you might want a second opinion and our oncologists can provide that. Again, you can make an appointment for a second opinion by calling 877-442-3324.
    I hope that helps and wish you the best.

  16. What sunscreen do you recommend? Avobenzone….RCote ….it is all very confusing. A recommendation would be appreciated. I slather on the Coppertone Sport and wear a hat and yet I have skin cancer.

  17. Hello! I’ve recently been diagnosed with Melanoma in situ. Does this mean I have cancer? I’ve seen multiple different answers to this. I understand the Melanoma is simply on the outer layer of skin and has not spread, but is it still considered cancer? Thanks for your help!

  18. hi jennifer, i was just diagnosed this week with a mucosal melanoma of the cervix. there are only 70 known cases worldwide. basically there aren’t any typical treatments for this kind of cancer. what oncologist do you recommend i see at the hospital?

  19. Hi Dr. Lin,

    My wife is 38 and has been diagnosed with melanoma in situ by her dermatologist. She has had a few abnormal moles removed in the past but never melanoma. Would you recommend a second opinion by an oncologist?

    Jack M.

  20. I have have just been diagnosed with melanoma had MOH’s surgery and and the first stage if a forehead flap to the nose. I am blessed that it was in situ, my next surgery is 8/21 and I will be booking an appointment at the clinic. What can I expect from here ?

  21. There’s a lot we still don’t know about melanoma. When I was diagnosed at 23, it seemed like I was told something different by every single dr I went to. I wouldn’t consider my sun exposure ”excessive” considering I’ve never had a job that required me to be in the sun for long periods of time and I live in a region with short summers. In fact, I’ve had to take vitamin D supplements since elementary school. The effected mole was a large irregular birth mark on my back. It was removed and tested when I was in high school and the results came back normal, so when it partially grew back, the dr said she probably just didn’t go ”deep enough” and not to worry about it, so I didn’t. Basically what I was left with was a large birthmark with a piece missing out the middle and a false sense of security.. When dr’s would ask me about it, they would ask me questions like how long I’d had it and if I ever used a tanning bed and determine that it was probably benign and not test it, considering I’d never used a tanning bed and especially considering it had came back benign in the past. My first time ever using a tanning bed was the spring I was diagnosed. Using the tanning bed was probably the only reason it was tested it to begin with. Later my dr said it would have had to have been melanoma already, considering the staging (T1B). Given my age and the fact that the tumor was on my torso and not more sun exposed areas of my body like my arms or my legs, my dr said I could carry a gene for melanoma. It wasn’t until after my diagnosis I found out my great grandfather died of state 4 metastatic melanoma and I have an aunt who had melanoma. My parents never enforced the sunscreen rule.. I didn’t burn easily and it wasn’t well understood back then that cancer ran in families, and, like any kid, I spent a lot of time outside in the sun. Luckily my margins and my lymph nodes came back clear and I’m not taking any chances with my daughter that was born in Feb. I cant control genetics, but now that I know she’s high risk, I can catch it early enough. Take it from me, know your family history. It’s not just an environmental cancer, like many people think. If your not sure, get it removed.

  22. The article says: ”A good way to know that you are applying enough sunscreen is to use the measurement of a shot glass of sunscreen for exposed sites.” How do you define 1 exposed site? Do you mean face as 1 exposed site. 1 arm or 1 leg as another? Please clarify because if clearer could be very useful advice. Thanks.

  23. My daughter was diagnosed with melanoma at 21. She had a sentinel node biopsy and was told it was gone. For two years it spread through her blood stream. She was 23. She started feeling ill, had horrible back and leg pain and was dropping weight. They kept saying she had a virus. She then started getting subcutaneous nodules. Finally they biopsies one and it was melanoma. By that time it was everywhere. She lived 11 months.Last year I was diagnosed with melanoma. They did wide excision and said I was good. I am fair, was strawberry blonde, freckled, had tons of blistering sunburns, tanned in tanning beds for years. I have also had 2 basil cell and 4 squamous. Should I worry that the same thing will happen to me?

    1. Dear Evelyn —

      We are so sorry to hear about the loss of your daughter. Sending you and your family our deepest condolences.

      Unfortunately, we cannot give out any medical advice on this blog or over email. However, it is important to keep an open conversation with your physician and care team about you and your daughter’s history. It is best to bring up these concerns with your doctor to talk about ways to monitor your risks and prevent further health problems.

      Wishing you all the best.

  24. For sun protective clothing, there are many brands offering hats, shirts, pants, etc. with a rating. Google the topic., and are examples. (The last two are not inexpensive.) I had a melanoma removed from my cheek at Brigham & Womens 10 years ago March 17, and have had no recurrence. Rit (the dye maker) has a product which you can use to apply a SPF factor to your existing clothing; I do not know if it is really effective. When I am mowing my lawn, doing yard work, veg. gardening, etc., I wear this straw hat with oversized 4 inch brim all around it — it is a bargain. I have not found a men’s hat with a wider brim.

  25. What do you know about whether their is any effect in treating melanoma with polio vaccine?

    1. Dear Pat —
      Thank you for your comment and for reading Insight. Experts recommend using the “ABCDE rule” to help determine when a physician should see a mole or skin change:

      A for asymmetry: One half is differently shaped than the other
      B for border irregularity: Jagged or blurred edges
      C for color: The pigmentation is not consistent
      D for diameter: Moles greater than six millimeters (the size of a pencil eraser)
      E for evolving: A mole changing in size, shape or color

      Other symptoms of melanoma can include satellite moles (new moles that grow near an existing mole), or areas that ooze, bleed, or are ulcerated.

      I hope this is helpful! More information about skin cancer screening recommendations is available here.

  26. I had a biopsy last week; the result was the scary word, Melanoma. Yesterday, I had more taken from the area, well outside of the margins. I should hear the results from this next week. My question: Should I make an appointment with an oncologist? I will be seeing my Dermotologist every 3 months for two years and every 6 months after that; in addition, I don’t know if I should see an oncologist too.
    Thank you

    1. Dear Tammy–
      I am sorry to hear about your recent health concerns. Unfortunately, we cannot give out medical advice on this blog or over email. It is best to discuss your questions and concerns with your physician or dermatologist – they will be able to recommend any next steps you should take.
      Wishing you all the best.

  27. Why is there a difference in opinion in the medical field whether melanoma in situ is considered cancer or not? I was diagnosed two weeks ago and referred to a plastic surgeon by my dermatologist to remove the rest of the “spot” since it is on my face. I’m having to wait another two weeks to see the plastic surgeon for a “consultation,” then who knows how much longer it will be. I NEVER spent a lot of time outdoors (don’t like the blistering sun), never went to a tanning salon and the “spot” does not have the characteristics of the ABCDE’s. I went to the dermatologist to have a couple of skin tags, and what I thought was either an age spot or freckle, removed (which I had for three years), for cosmetic reasons. She was suspicious of the “spot” (which was flat and light brown) because I had no other similarities on my face and suggested a biopsy, to which I agreed.

  28. One clarification please: if I put on a 30+ sunscreen before I apply make up at say 8 am, then am in an office until noon, do I have to reapply it before I go out for a lunch time walk? Does the reapply rule assume that the wearer is in the sun and active for those two hours. To be honest, I would like to avoid the hassle of reapplying the sunscreen, make up etc.

  29. I have recently been diagnosed with Stage IV Melanoma, Unknown Primary Tumor. The metastasis on my left calf has been removed and I am currently NED. Surgery and observation is current treatment plan; I have not had a recurrence as of my original diagnosis (2 months). Are there any clinical trials available for my situation?

    1. Dear Mary —
      Thank you for connecting with us and reading Insight. We are so sorry to hear about your recent diagnosis.

      Unfortunately, we cannot give out specific medical advice on this blog or over email. However, the links below provide a list of clinical trials both at Dana-Farber and across the country.

      Dana-Farber Clinical Trials

      We hope this is helpful and wish you all the best.

  30. 60 year old male, melanoma site on back removed. Sentinel lymph nodes biopsy indicates 3 of 4 nodes clean. 1 lymph node had 3 spots of micro cell melanoma. diagnosed with melanoma stage IIIA. Receiving treatment at MGH. The initial spot on my back looked like a bug bite. It was itchy and a pink spot, I initially thought it was a tick bite. All the doctors said it was very unusual, I would be happy to share the photo so that others may get some benefit from recognizing early onset of a unique melanoma. Awaiting results of lymph nodes pathology from regional lymphadenectomy.

Comments are closed.