恶性黑色素瘤与痣看起来是不同的

　　一篇发表于1月4日皮肤科学志上初期研究结果显示，侦测危险的恶性黑色素瘤可能不如许多恐惧般困难；研究者指出，藉由辨认丑小鸭病征，恶性黑色素瘤通常看起来与周围的痣不同；他们表示，这两者是非常不同的，即使未受过训练的人们通常也可以确认出这些令人担心的斑点，并且促使他们去看医师；资深作者纽约Sloan-Kettering纪念癌症中心Ashfaq Marghoob医师向Medscape肿瘤学表示，我们的研究结果显示，一般大众可能和医师一样有办法分辨恶性黑色素瘤。
　　
　　透过鉴别确认，医师与病患一样可以区分恶性黑色素瘤与周围的痣；我们发现透过辨认丑小鸭病征来区分恶性黑色素瘤的敏感度是相当高的；Marghoob医师附带表示，他鼓励临床医师考虑这个过去被忽略的重要方法。
　　
　　他进一步表示，早期侦测恶性黑色素瘤在预防死亡上仍是最重要的，大众健康讯息多年来都将重点放在ABCD守则，就像Marghoob医师过去强调这是有效的一样；这项规则代表癌化黑色素瘤倾向于：
　　A. 不对称的
　　B. 有不规则的边缘
　　C. 颜色不一致
　　D. 半径较大，通常比铅笔的橡皮擦大。
　　
　　不幸的，Marghoob医师表示，这项规则不能侦测某些黑色素瘤，因为我们已经察觉一群黑色素瘤并不会以ABCD特征表现；但是，他附带表示，透过鉴别确认，这些黑色素瘤经常与周围的痣长得不同且是坑坑疤疤的。
　　
　　他指出，在自我皮肤检查时，病患应该找寻以ABCD表现的病灶，且寻找与周围的痣长得不同的病灶，这样的合并检查方法应该可以改善早期侦测恶性黑色素瘤的成功率。
　　
　　【透过自我检查改善ABCD规则】
　　由Sloan-Kettering纪念癌症中心Alon Scope医师领导的研究者们，取得12位来自标准化病患图表资料库病患背部照片，每位参与者至少有8个非典型痣，5位病患中有1位已经被确认为黑色素瘤的病灶；在整体34位试验参与者中，有8位色素沉着病灶的专家、13位一般皮肤科医师、5位皮肤科护理人员以及8位非临床医疗人员，这些参与者被要求评估这些照片，并确认出与其他所有非典型痣不同的病灶。
　　
　　5个黑色素瘤以及140个良性病灶中仅有3个（2.1%）被三分之二的受试者区分为不同的，也就是所谓的丑小鸭病征；显然的，恶性黑色素瘤对至少85%的参与者来说是不同的；研究者报告，将良性病灶认为是不同的同意率至多为76%。
　　
　　作者写道，虽然丑小鸭病征的敏感度、专一度、与诊断正确度端看临床专业经验，但这些参数的价值对于所有参与者族群都是很好的。
　　
　　【丑小鸭病征的敏感度与专一度】

族群	被认为不同的所有病灶， % (95% CI)	病灶， % (95% CI)
整体
– 敏感度 – 专一度	90 (87 – 95) 85 (83 – 88)	86 (81 – 91) 87 (83 – 90)
专业 皮肤科 医师
– 敏感度 – 专一度	100 (91 – 100) 89 (86 – 92)	87 (78 – 98) 93 (90 – 95)
一般 皮肤科 医师
– 敏感度 – 专一度	89 (83 – 96) 86 (83 – 89)	85 (76 – 94) 90 (85 – 93)
皮肤科护理人员
– 敏感度 – 专一度	88 (80 – 97) 80 (76 – 84)	88 (75 – 100) 79 (64-87)
非临床医疗人员
– 敏感度 – 专一度	85 (77 – 94) 83 (80 – 86)	85 (76 – 95) 83 (71 – 90)

CI为信赖区间
　　
　　研究者指出，这项研究中的非临床人员也有部份临床经验，因为他们是医疗工作人员，这项事实引发了这项筛检是否适用于一般大众，然而，他们表示，进行自我检查处于恶性黑色素瘤高度风险的病患，可能较容易接受资讯且有更大后续追踪的动机；高风险病患，尤其是那些有多重非典型痣的，可能是最适用于黑色素瘤自我检查的病患。
　　
　　在与Medscape肿瘤学谈话时，Marghoob医师强调这项初期试验结果是根据虚拟情况下一群少数的样本，目前正在进行更大型样本病患与观察者的研究来测试丑小鸭病征。
　　
　　Marghoob医师指出，另一个潜在的令人困扰的限制是鉴别确认，良性病灶，例如脂漏性角质炎可能也会出现丑小鸭病征，这可能造成不必要的求诊。
　　
　　作者的结论是，对于引领恶性黑色素瘤被认为不同的特质，例如特定的颜色、大小与形状进一步的评估，可能进一步改善丑小鸭病征在判断黑色素瘤上的准确性以及更好之观察者间的一致性。
　　
　　研究者表示无相关资金上的关系。
 

Malignant Melanomas Often Look Noticeably Different From Other Moles

By Allison Gandey
Medscape Medical News

 

Detecting dangerous malignant melanomas might not be as difficult as many fear. Dubbed ugly ducklings, researchers report that melanomas tend to look very different from surrounding moles. They say they are so different that even untrained individuals can often identify worrisome spots that prompt a visit to the doctor's office. The preliminary study appears in the January issue of Archives of Dermatology. "Our study shows that the lay public may be as qualified as physicians to detect malignant melanomas," senior author Ashfaq Marghoob, MD, from the Memorial Sloan-Kettering Cancer Center in New York, told Medscape Oncology.

Using differential recognition, physicians and patients alike can distinguish ugly melanomas from surrounding moles. "We found the sensitivity of the ugly-duckling sign was quite high," Dr. Marghoob added, and he encouraged clinicians to consider this important yet perhaps-overlooked method.

"Detecting early malignant melanoma remains paramount in preventing death," he continued. The public-health message for many years has focused mainly on the ABCD rule — an emphasis that Dr. Marghoob said has been effective. The rule suggests that cancerous melanoma tend to:

A. Be asymmetric.
B. Have border irregularities.
C. Have variations in color.
D. Be large in diameter — often bigger than the size of the eraser of a pencil.

"Unfortunately," Dr. Marghoob said, "this rule does not detect some melanomas, since we have come to appreciate that there are a group of melanomas that do not manifest the ABCD features." But, he added, these melanomas often look very different from surrounding moles and can still be flagged using differential recognition.

"During self skin examination, patients should be looking for lesions that manifest the ABCDs and for lesions that look different from surrounding moles," he said. "This combined approach for looking at skin should improve on the early detection of malignant melanoma."

Improving on the ABCDs of Self Examination

Led by Alon Scope, MD, also from Memorial Sloan-Kettering, the researchers obtained images of the backs of 12 patients from a database of standardized patient images. Each participant had at least 8 atypical moles, and 5 patients had 1 lesion that had been confirmed as a melanoma. A total of 34 study participants — 8 pigmented lesion experts, 13 general dermatologists, 5 dermatology nurses, and 8 nonclinical medical staff — were asked to evaluate the images and identify lesions that looked different from all other atypical moles.

All 5 melanomas and only 3 of 140 benign lesions (2.1%) were classified by two-thirds of the participants as different — so-called ugly ducklings. It was apparent that the malignant melanomas were different to at least 85% of participants. The agreement rate on the benign lesions perceived as being different was 76% at most, the researchers report.

"Although the sensitivity, specificity, and diagnostic accuracy of the ugly-duckling sign depended on clinical expertise, the values for these parameters were good in all subgroups of participants," the authors write.

Sensitivity and Specificity for the Ugly-Duckling Sign

Group	All Lesions Perceived as Different, % (95% CI)	Biopsy, % (95% CI)
Overall
– Sensitivity – Specificity	90 (87 – 95) 85 (83 – 88)	86 (81 – 91) 87 (83 – 90)
Expert dermatologists
– Sensitivity – Specificity	100 (91 – 100) 89 (86 – 92)	87 (78 – 98) 93 (90 – 95)
General dermatologists
– Sensitivity – Specificity	89 (83 – 96) 86 (83 – 89)	85 (76 – 94) 90 (85 – 93)
Dermatology nurses
– Sensitivity – Specificity	88 (80 – 97) 80 (76 – 84)	88 (75 – 100) 79 (64-87)
Nonclinical medical staff
– Sensitivity – Specificity	85 (77 – 94) 83 (80 – 86)	85 (76 – 95) 83 (71 – 90)

CI = confidence interval

The researchers point out that the nonclinicians used in this study had some exposure to clinical practice because they were medical staff members. This fact calls into question whether the findings are applicable for screening by the general public. "However," they note, "patients at higher malignant melanoma risk who perform skin self examination may also be better informed and more motivated toward surveillance. Higher-risk patients, particularly those with multiple atypical moles, are probably the individuals for whom melanoma screening efforts are most applicable."

Speaking to Medscape Oncology, Dr. Marghoob emphasized that this preliminary study is based on a small sample in a virtual setting. Efforts are under way to test the ugly-duckling sign in a larger sample of patients and observers.

Dr. Marghoob pointed to another potentially troublesome limitation of differential recognition. Benign lesions such as seborrheic keratosis can appear as ugly-duckling lesions and prompt unnecessary office visits.

The authors conclude: "Further evaluation of the attributes of a malignant melanoma that lead it to be perceived as different — such as specific color, size, and shape — may allow refinement of the ugly-duckling sign and result in even better interobserver agreement."

The researchers have disclosed no relevant financial relationships.

Arch Dermatol. 2008; 144:58-64. Abstract