How long does it take for melanoma in situ to spread

Making a melanoma diagnosis means gathering as much information about your skin cancer as possible. One key step is determining the cancer’s stage, which is a measure of the amount and severity of cancer in the body. Staging helps your doctor understand how best to treat the cancer, and is used when discussing survival rates.

Following stage 0 (called melanoma in situ), the degrees of melanoma range from stage I through stage IV, with higher numbers indicating further spreading of the cancer throughout the body.

There are three factors commonly used to determine melanoma staging, and they’re represented by the TNM system. The first factor is the severity of the primary tumor (T), which includes how thick the tumor is and whether the skin covering it has broken. The second factor is whether the cancer has spread to nearby lymph nodes (N). The third factor is whether the cancer has spread, or metastasized (M), to lymph nodes farther away in the body or other organs.

Stage I Melanoma

The earliest stage of melanoma, stage 0, is limited to the outermost skin layer called the epidermis. This is a noninvasive stage, which is also called melanoma “in situ,” meaning “in its original place.”

With stage I melanoma, the tumor’s thickness is 1mm or less. This tumor may or may not have ulcerated, and it isn’t yet believed to have spread beyond the original site.

Treatments for Stage I Melanoma

Your doctor will most likely treat stage 1 melanoma with surgery called wide excision, which cuts out the melanoma along with a margin of healthy surrounding skin. The amount of healthy skin removed is determined by the location and the thickness of the melanoma being treated.

While wide excision surgery is often the only treatment necessary, in some cases a doctor may also choose to check for cancer in nearby lymph nodes by performing a sentinel lymph node biopsy. If cancer cells are found in the lymph nodes, further treatment will become necessary, such as a lymph node dissection (removing nearby lymph nodes), chemotherapy, immunotherapy, or targeted therapies.

Stage II Melanoma

With stage II melanoma, the tumor has penetrated the skin deeper than 1 mm. It may have ulcerated, but not in all cases. Although a tumor at this stage may not have advanced, it has a high risk of spreading. A thicker melanoma, such as a tumor more than 4 mm, has a very high risk of spreading. 

Treatments for Stage II Melanoma

As with stage I, stage II melanoma is typically treated with wide excision surgery, which cuts out the melanoma along with a margin of healthy surrounding skin. In the case of stage II melanoma, many doctors will recommend looking for cancer in nearby lymph nodes by performing a sentinel lymph node biopsy, which may necessitate further treatment if cancer cells are found.

Corresponding Author: Craig Bauman, The Centre for Family Medicine, 25 Joseph St., Kitchener, ON N2G 4X6, Tel: (519) 578-2100 ext 255, e-mail: ac.retsamcm@namuab

Copyright © JCCA 2018

Abstract

Introduction

Melanoma can be a fatal form of skin cancer. The prognosis rapidly deteriorates from the in situ stage (stage 0) to stage 4. As such, early detection and treatment are key.

Case Presentation

A middle-aged patient, who was also a chiropractor, self-identified a small skin lesion using the Chiropractors Guide to Skin Cancer. The primary care physician made a dermatology referral, and biopsy identified melanoma. Surgery was subsequently booked and the lesion was excised with a 5 mm margin. The final pathology report confirmed a diagnosis of melanoma in situ.

Summary

As primary contact health care providers chiropractors can play a significant role in the potential identification and initiation of investigations into various possible dermatological disorders including skin cancer. Efforts should be made to diagnose melanoma at the in situ stage to ensure the best outcome.

Keywords: melanoma, self-exam, skin cancer, chiropractic

Résumé

Introduction

Le mélanome est un cancer de la peau pouvant être fatal. Le pronostic s’assombrit rapidement entre le stade 0 (mélanome in situ) et le stade 4. Un dépistage et un traitement précoces sont essentiels.

Présentation du cas

Un patient d’âge mûr, qui était aussi un chiropraticien, a décelé chez lui une petite lésion cutanée à l’aide du Chiropractors Guide to Skin Cancer (guide servant à aider le chiropraticien à dépister un cancer de la peau). Un médecin de premier recours l’a dirigé vers un dermatologue; l’examen de la biopsie a révélé un mélanome. Un rendez-vous en chirurgie a été pris. La lésion et une marge chirurgicale de 5 mm ont été excisées. Le rapport final du laboratoire de pathologie a confirmé le diagnostic d’un mélanome in situ.

Résumé

À titre de fournisseurs de soins de santé primaires, les chiropraticiens peuvent jouer un rôle important dans le dépistage de diverses affections cutanées dont le cancer de la peau et l’amorce des examens exploratoires. On devrait déployer des efforts pour que le mélanome soit diagnostiqué au stade 0 (mélanome in situ) pour assurer la meilleure issue possible.

MOTS-CLÉS: mélanome, auto-examen, cancer de la peau, chiropratique

Introduction

Melanoma is the most deadly form of skin cancer (Figure 1).1 If detected at the in situ stage and properly treated the risk of mortality is essentially negligible.2 At the in situ stage the malignant tumour is restricted to the outer layers of the skin (epidermis).3 The cancer cells at this stage are therefore only in the upper layer of the skin and have not seeded into the dermis or beyond.3

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Figure 1

An example of a melanoma (source: https://commons.wikimedia.org/wiki/File:Melanoma.jpg [Accessed April 28 2017]).

Chiropractors often see patients on an ongoing basis in clinical practice and are in an excellent position to observe the evolution of skin pathology and initiate the correct referral to the patient’s physician. This report documents a case involving a chiropractor who was diagnosed with melanoma in situ. This case is also presented from the patient’s perspective to help illustrate the patient experience as well as the steps to proper management of this common but potentially deadly disorder.

Case Presentation

History

I am a 51-year-old male chiropractor. My melanoma in situ experience begins in my youth. I was an avid windsurfer and had frequent sunburns of my feet from standing on the surfboard. I had a small mole on the dorsum of my left foot for as long as I can remember. Having had so much sun exposure from outdoor sports, I realized that I was at risk for skin cancer. I would occasionally check my skin for any unusual moles. When I received the Chiropractors Guide to Skin Cancer4 a number of years ago, I read it from cover to cover several times and used the photographs as a resource for checking my own skin.

About 18 months prior to my skin cancer diagnosis, I noticed that the mole on the dorsum of my foot appeared larger. It was flat, multi-coloured, and asymmetrical in shape, had an irregular border and was about 4 mm in diameter. Contained in the Guide was information on the ABCDE’s of melanoma (Table 1).4 The mole on my foot had several of these concerning features, but it was smaller than the 6 mm diameter size typical of melanoma lesions.4

Table 1

The ABCDE’s of melanoma.4–7

CategoryDescriptionAAsymmetry of shape of one half of the lesion compared to the other halfBBorder of the lesion is irregular, jagged, notched or may blur pigment into the surrounding skinCColour of the lesion may be varied with shades of black, brown, blue and whiteDDiameter of the lesion is greater than 6 mm, or larger than the end of an eraserEEvolution of the size, shape, elevation, surface or colour of the lesion has occurred over time

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The “Ugly Duckling” sign. One lesion stands out as different from all the others.

I decided to make an appointment with my family physician. I showed the physician the lesion, but he was not concerned. I continued to observe the mole and a year later it had grown to 5 mm in diameter. By this time my family doctor had retired and I was taken on by another family physician. I made an appointment with this physician and showed her the area of concern. Again the lesion was deemed unremarkable. I also showed the physician another lesion on my thigh that I had been following and this resulted in a dermatologist referral. At that appointment, the dermatologist used cryotherapy to remove the lesion on my thigh. I asked the dermatologist to perform a full body skin check as well and a lesion on my back was identified along with the one on my foot, and these were subsequently scheduled for biopsy.

Intervention and Outcome

I returned to the dermatologist for the superficial shave biopsies. Briefly, superficial shave biopsies involve removal of a thin disc of tissue, typically by scalpel, yielding a flat thin specimen limited to the epidermis and upper dermis less than 1 mm in total depth.8 In my case, the dermatologist said that he “wasn’t too worried” but was performing the biopsies to be safe. He said they would get the results in four weeks and if I didn’t hear anything from them, this would mean that everything was fine. I received a call 10 days later, however, to come in for a follow up appointment. I really wasn’t concerned and assumed they just wanted to see how the biopsy sites were healing. The dermatologist walked into the room with a concerned look. He said the lesion on my back was only a dysplastic nevus (i.e. an unusual-looking benign, noncancerous mole).9 The lesion on my foot however was melanoma in situ. I zoned out hearing those words, knowing the seriousness of melanoma. He said I would require surgery and possibly a skin graft. He gave me a copy of the pathology report. There was no pathology extending to the deep margin on the specimen; but the tumour did extend to one peripheral margin, which meant more tumour may remain with a potentially higher stage and thus a greater risk of death. The dermatologist recommended that I return in four months. He also informed me that in the first two years after diagnosis there is a higher chance of other melanomas appearing. He therefore instructed me to perform regular skin checks and to return sooner than four months if I found anything suspicious.

Two weeks later I saw the general surgeon. He said no graft would be required; however a 5 mm margin of skin surrounding the lesion would have to be removed and several stitches would be needed. The surgeon indicated that the final pathology report from that specimen would confirm if it was in fact melanoma in situ or a higher stage which would then require further surgery. The surgery was performed with a local anesthetic and a piece of skin (about the size of a Canadian loonie) was removed. The stitches made the skin on the dorsum of my foot quite tight. I walked with a limp, not out of pain, but to prevent the stitches from being pulled out. I worked later that day being careful to not stress the area. I had some pain when the freezing wore off, but only required one extra-strength ibuprofen that first night for relief. The skin slowly stretched out and the pain reduced over the next three weeks. I stopped lower extremity exercises until the stitches could be removed.

Three and a half weeks later, I telephoned the surgeon’s office and was told the final pathology report confirmed no residual disease and therefore a final diagnosis of melanoma in situ. I felt such relief at hearing that news. The next day I returned to the surgeon and the stitches were removed. Currently, I continue to perform regular monthly skin checks on myself, and I follow-up with the dermatologist every 4 months for ongoing melanoma screening.

Discussion

Melanoma can be screened for using the ABCDE’s of melanoma (see Table 1).4–7 The lesion diameter of 6 mm is an accurate size parameter for determining the risk of melanoma.5 There is a higher risk of invasive melanoma (i.e. seeding of melanoma beyond the epidermis) when moles are greater than the 6 mm diameter size.7 In Australia doctors have been screening for and identifying melanomas smaller than 6 mm, however evidence suggests that this method does not necessarily improve diagnostic accuracy or patient prognosis.5,7 A more important parameter than size in detecting early-stage melanomas may be whether the lesion is evolving (i.e. change of size, shape, elevation, surface or colour of lesion over time).5,7 In the current case, the melanoma lesion was smaller than 6 mm in diameter yet showed signs of evolution in size over the course of 12 months. The lesion also exhibited signs of asymmetry, border irregularity, and colour variegation.

The basic tumour staging of melanoma includes five stages, stage 0 (in situ) to stage IV.10 The survival rates based on this staging system are listed in Table 2 and the main types of melanoma are listed in Table 3.10,11,12 In general, the prognosis deteriorates from the in situ stage (stage 0) to stage IV. There is also a more detailed staging approach that is often used known as the TNM system.10 T describes the thickness of the melanoma, N describes how many lymph nodes are affected, and M describes metastasis or spread to distant organs of the body.10 In either case, every effort should be made to diagnose melanoma at the in situ stage as the prognosis rapidly deteriorates with stage increase.11

Table 2

Survival rates of melanoma based on stage.2,10,11

StageSurvival rate0 (in situ)99.9% 5-year survival; 98.9% 10-year survivalI/II89 to 95% 5-year survivalII45 to 79% 5-year survivalIII24 to 70% 5-year survivalIV7 to 19% 5-year survival

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Table 3

The four main types of melanoma.12

Type% of casesSuperficial spreading melanoma70Nodular melanoma15Lentigo maligna melanoma13Acral lentiginous melanoma2–3

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When compared to the final excision pathology report, superficial shave biopsy has a depth accuracy rate for staging in the range of 81–88%.2,13 For lesions that are less than 1 mm in depth the accuracy is 96%.8 If the superficial shave biopsy margins are clear (i.e. there are no tumour cells extending beyond the edge of the biopsy specimen, either at the sides or the bottom) the staging accuracy is 93%.13 In the current case the tumour extended to one peripheral margin of the biopsy specimen, slightly reducing the accuracy rate to 85%.13 Nevertheless, a diagnosis of melanoma in situ was made.

Surgery to remove the lesion and surrounding skin is the gold standard treatment for melanoma.14 For melanoma in situ, the surgical margin includes skin removal up to 5 mm around the mole.14,15 Tumours with a depth of less than 1 mm also do not require sentinel lymph node biopsy.15 For higher stage/invasive tumours (i.e. stages I to IV) the surgical margin surrounding the lesion can be as great as 10 to 20 mm.14,15 In addition, sentinel (e.g. inguinal or axillary) lymph node biopsy, with possible surgical removal, is normally required.14,15

The frequency of melanoma is increasing.14,16 Estimates for 2016 in the United States were 76,380 new cases of invasive melanoma and 68,480 new cases of melanoma in situ.14 The incidence rate and death rate of melanoma have also increased significantly among Canadian men and women over the past 25 years.16

The risk of recurrence and higher risk of additional new melanomas after diagnosis warrants long-term skin checks by a dermatologist and self-exams by the patient.17 A web link to the Skin Cancer Foundation (http://www.skincancer.org/skin-cancer-information/early-detection/step-by-step-self-examination) provides patients with information on how to conduct a self-exam of their skin and how to properly document their findings.18,19 Taking a dated picture of a suspicious lesion next to a ruler allows patients to monitor for changes and notify their physician as required. In all cases the patient should be proactive and advocate for themselves in the health care system.

Although preliminary, some research has shown an association between regular white wine consumption, use of growth hormone, Parkinson’s disease, psychosocial stress, or the use of biologic medication (e.g. TNF-alpha inhibitors for Crohn’s disease) and increased risk of melanoma.20–24 Exercise, vitamin D, or coffee consumption may help to reduce the risk of melanoma;25–28 however further investigations on these and other dietary/lifestyle factors and associated effects on melanoma risk are needed.

Limitations

A key limitation of this paper is the inherent/unintentional bias that the principal author may bring to the report as it is written from the patient’s perspective. Moreover, this case report may have biased observations in how the principal author recounted the clinical details.

Summary

The patient in this case (CAB) has returned to exercising and carrying on with normal life. Regular skin checks by the dermatologist will continue to occur on a long-term basis.17 Three of the authors on this paper (CAB, TD, HD) have been diagnosed with melanoma. We have written this paper to increase chiropractors’ awareness of this common skin disorder. Doctors of chiropractic are primary care providers in an excellent position to detect and monitor skin lesions and refer as required. The earlier melanoma is detected, the greater the chance of survival.29 Hence, chiropractic screening and early detection of suspicious skin lesions in clinical practice could save a patient’s life – or as in the current case, the chiropractor’s.

Key Points

• Melanoma is the most deadly form of skin cancer

• Regular skin checks by the physician and patient are recommended

• All efforts should be made to detect melanoma at the in situ stage

• Treatment at the in situ stage has a nearly negligible mortality rate

Footnotes

The involved patient provided consent for case publication.

The authors have no disclaimers, competing interests, or sources of support or funding to report in the preparation of this manuscript.

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