This common "birthmark" may be a disease: "coffee spots" that cannot be ignored

Coffee-fronted spots are a common "birthmark". Apart from affecting the appearance, they are generally painless and not itchy, and are often ignored. However, when coffee-fronted spots reach a certain size and number, they may be a sign of disease! Why do coffee-fronted spots appear? Can coffee-fronted spots become malignant? What should I do if I find coffee-fronted spots? Are coffee-fronted spots "marks" or "diseases"? Which coffee-fronted spots may indicate neurofibromatosis type 1? This article will take you to find out.

01 What do coffee spots look like?

Coffee-and-milk spots are also called cafe au lait spots. As the name suggests, the color is like coffee with milk added, slightly darker than normal skin. They can be light brown, tan or dark brown patches. The color of the same coffee-and-milk spot is relatively uniform. Most coffee-and-milk spots are round, oval or irregular in shape. A few have jagged edges, clearly demarcated from normal skin. Small coffee-and-milk spots are as small as rice grains, while large coffee-and-milk spots can exceed the palm of your hand and be tens of centimeters in diameter.

Café au lait spots are usually found at birth or soon after birth and are considered a type of birthmark. They increase in size with age and do not disappear on their own. It has been reported that 10% to 20% of people have café au lait spots, which can be located anywhere on the body, with the majority occurring on the trunk, buttocks, and limbs, and a few on the face [1,2].

Figure 1 Café au lait spots[3]

02 Are all birthmarks café-au-lait spots?

Café au lait spots usually appear when the baby is born, and may also gradually appear after birth, but please note that not all birthmarks are café au lait spots! Common "birthmarks" also include Mongolian spots, nevus of Ota, black hairy nevus and other types, which can be judged comprehensively based on the color, shape, size and other factors of the skin lesions.

Mongolian spots are mainly gray-green, dark blue or gray-brown patches on the buttocks or waist that are present at birth. The surface of the patches is flat and smooth, and most of them may slowly fade with age. Ota's nevus appears as gray-blue, blue-gray or black patches distributed along the ophthalmic and maxillary branches of the trigeminal nerve. The patches vary in size from several centimeters, with uneven coloring and unclear boundaries with the surrounding skin. The color of the patches will deepen with age. Black hairy nevus appears as brown-black or black patches that are slightly higher than the skin surface. They often have hair that is thicker and darker than normal hair and grows with age.

Figure 2 Other common “birthmarks” besides café-au-lait spots[4-6]

03 Why do coffee spots appear?

How are coffee spots formed? Is there any relationship between coffee spots and sun exposure? Although the pathogenesis of coffee spots is not yet fully understood, its occurrence is not necessarily related to sun exposure. Coffee spots are a type of pigmented skin disease. The melanin in the melanocytes and keratinocytes in the pigmented spots increases, and the melanocytes become overactive, producing a large amount of melanin, forming pigmented spots.

04 Can coffee spots become malignant? How should they be treated?

Café au lait spots themselves will not become malignant or cause any functional impairment. They generally do not require treatment, and there are currently no effective oral or topical medications. However, if they grow on exposed areas such as the face and affect the appearance, laser and photon treatments can be used. Laser treatment is currently the main treatment for café au lait spots. Generally speaking, the treatment of common café au lait spots can achieve satisfactory results. The clearance rate of 75% of patients with café au lait spots exceeds 50%. For common café au lait spots, QS-1064-nm Nd:YAG laser treatment has the best effect and is less likely to cause pigmentation and depigmentation [7].

05 Are coffee stains a sign of “memory” or “disease”?

Physiological coffee-top spots do not affect health, but mainly affect appearance. However, it is important to be aware that although coffee-top spots are not uncommon in the normal population, they may also be a sign of certain systemic diseases, such as neurofibromatosis, Albright syndrome, tuberous sclerosis, Watson syndrome, etc. Coffee-top spots that appear in different diseases may have different characteristics and be accompanied by other abnormal manifestations.

Table 1 Differentiation between physiological and pathological café-au-lait spots

Figure 3 Physiological and pathological coffee-coffee spots

Of course, the specific determination of whether the coffee spots are physiological or pathological still depends on the examination and evaluation of a professional doctor.

Which café-au-lait spots may indicate neurofibromatosis type 1?

If there are multiple café-au-lait spots (more than 6, with a diameter greater than 5mm before puberty and greater than 15mm after puberty), you need to be alert to the possibility of neurofibromatosis type 1. At this time, you should closely monitor whether there are tumors in various systems of the body and whether there are abnormal growth and development. Once these abnormal signs appear, it is recommended to seek medical attention in time for a clear diagnosis!

07 What is neurofibromatosis type 1?

Neurofibromatosis type 1 (NF1) is an autosomal dominant genetic disease of the nervous system caused by mutations in the NF1 gene. Its global incidence is about 1/3000, with about 50% of patients having familial genetic mutations and the rest having sporadic mutations. Typical clinical symptoms of NF1 include café au lait spots, multiple neurofibromas, axillary or groin freckles, etc. The clinical symptoms of this disease vary greatly, which can cause disfigurement and functional impairment, increase the risk of tumor malignancy, seriously affect the quality of life of patients, and bring a heavy psychological burden.

08 How is neurofibromatosis type 1 diagnosed?

The first "Expert Consensus on Clinical Diagnosis and Treatment of Neurofibromatosis Type 1" in China states that for patients without a parental history of the disease, NF1 can be diagnosed if ≥ 2 of the following clinical features are met; for patients with a parental history of the disease, NF1 can be diagnosed if ≥ 1 of the following clinical features is met[8]:

Table 2 Diagnostic criteria for neurofibromatosis type 1[8]

Figure 4 Diagnostic criteria for neurofibromatosis type 1 (Image source: Paopaojiayuan subscription account)

If a patient is suspected of having NF1, he or she should be evaluated by a professional neurofibroma medical team as soon as possible to avoid misdiagnosis and delayed treatment.

Conclusion

Coffee-fronted spots are a very common "birthmark" that generally only affect the appearance without harming the health of the body, but they may also be a sign of certain diseases! If there are multiple coffee-fronted spots (more than 6, with a diameter greater than 5mm before puberty and a diameter greater than 15mm after puberty), you need to be alert to the possibility of neurofibromatosis type 1. Neurofibromatosis type 1 is more complicated and varies greatly from person to person, requiring professional physicians to evaluate, diagnose and treat.