Dermatology Service, Department of Medicine, Memorial Sloan Kettering Cancer Center.
Dermatology Service, Department of Medicine, Memorial Sloan Kettering Cancer Center;
J Vis Exp. 2022 Aug 18(186). doi: 10.3791/63789.
Skin cancer is one of the most common cancers worldwide. Diagnosis relies on visual inspection and dermoscopy followed by biopsy for histopathological confirmation. While the sensitivity of dermoscopy is high, the lower specificity results in 70%-80% of the biopsies being diagnosed as benign lesions on histopathology (false positives on dermoscopy). Reflectance confocal microscopy (RCM) and optical coherence tomography (OCT) imaging can noninvasively guide the diagnosis of skin cancers. RCM visualizes cellular morphology in en-face layers. It has doubled the diagnostic specificity for melanoma and pigmented keratinocytic skin cancers over dermoscopy, halving the number of biopsies of benign lesions. RCM acquired billing codes in the USA and is now being integrated into clinics. However, limitations such as the shallow depth (~200 µm) of imaging, poor contrast for nonpigmented skin lesions, and imaging in en-face layers result in relatively lower specificity for the detection of nonpigmented basal cell carcinoma (BCCs) - superficial BCCs contiguous with the basal cell layer and deeper infiltrative BCCs. In contrast, OCT lacks cellular resolution but images tissue in vertical planes down to a depth of ~1 mm, which allows the detection of both superficial and deeper subtypes of BCCs. Thus, both techniques are essentially complementary. A "multi-modal," combined RCM-OCT device simultaneously images skin lesions in both en-face and vertical modes. It is useful for the diagnosis and management of BCCs (nonsurgical treatment for superficial BCCs vs. surgical treatment for deeper lesions). A marked improvement in specificity is obtained for detecting small, nonpigmented BCCs over RCM alone. RCM and RCM-OCT devices are bringing a major paradigm shift in the diagnosis and management of skin cancers; however, their use is currently limited to academic tertiary care centers and some private clinics. This paper familiarizes clinicians with these devices and their applications, addressing translational barriers into routine clinical workflow.
皮肤癌是全球最常见的癌症之一。诊断依赖于目视检查和皮肤镜检，然后进行活检以进行组织病理学确认。尽管皮肤镜检的敏感性很高，但较低的特异性导致 70%-80%的活检在组织病理学上被诊断为良性病变（皮肤镜检的假阳性）。反射共聚焦显微镜（RCM）和光相干断层扫描（OCT）成像可以无创性地指导皮肤癌的诊断。RCM 以面状层可视化细胞形态。与皮肤镜检相比，它将黑色素瘤和色素性角质形成细胞癌的诊断特异性提高了一倍，将良性病变的活检数量减少了一半。RCM 在 美国获得了计费代码，现在已整合到诊所中。然而，成像深度较浅（200 µm）、对非色素性皮肤病变对比度差以及面状层成像等局限性导致对非色素性基底细胞癌（BCC）的检测特异性相对较低 - 与基底细胞层相邻的浅层 BCC 和更深的浸润性 BCC。相比之下，OCT 缺乏细胞分辨率，但可在垂直平面上对组织成像，深度可达1mm，这使得可以检测到浅层和深层 BCC 亚型。因此，这两种技术本质上是互补的。一种“多模态”的 RCM-OCT 联合设备可同时以面状和垂直模式对皮肤病变进行成像。它对 BCC 的诊断和管理非常有用（浅层 BCC 的非手术治疗与深层病变的手术治疗）。与单独使用 RCM 相比，它可显著提高对小的、非色素性 BCC 的检测特异性。RCM 和 RCM-OCT 设备正在皮肤癌的诊断和管理方面带来重大的范式转变；然而，它们的使用目前仅限于学术性三级护理中心和一些私人诊所。本文使临床医生熟悉这些设备及其应用，解决了将其转化为常规临床工作流程的障碍。
