Faculty Bibliography

Importance: Limited therapies are available in patients with inoperable locally advanced cutaneous squamous cell carcinoma (cSCC). Objective: To determine the efficacy of programmed cell death 1 receptor (PD-1) inhibitors in locally advanced cSCC. Design, Setting, and Participants: A single patient with locally advanced cSCC who declined surgery and radiotherapy underwent treatment with pembrolizumab, an anti-PD-1 antibody, at an academic dermatologic surgery section and cancer center. The patient was followed up for clinical and radiologic regression of cSCC. With the use of NanoString to amplify potential biomarkers, immunohistochemistry, and immunofluorescence, the ex vivo expression of PD-1 and a ligand (PD-L2) was assessed in 38 cSCC biopsy specimens from 24 patients with cSCC. Expression of PD-L1 and PD-L2 in the cSCC microenvironment was defined. Intervention: Pembrolizumab, 2 mg/kg every 3 weeks, for 4 cycles. Main Outcomes and Measures: Expression of PD-L1 and PD-L2 in the cSCC microenvironment. Results: In 1 patient with locally advanced cSCC who was treated with pembrolizumab, nearly complete tumor regression was observed after 4 cycles of therapy. The NanoString technology used in 38 cSCC biopsy specimens from 24 patients with cSCC (19 men and 5 women; mean [SD] age, 76.4 [12.2] years) detected increased PD-1 and PD-L2 expression in high-risk cSCC. Immunohistochemical analysis confirmed enhanced expression of PD-1 and its ligands in cSCC with perineural invasion (mean [SEM] expression, 5.06 [1.27]; P = .05), superficial cSCC (mean [SEM] expression, 3.58 [1.50]; P = .15), organ transplant-associated cSCC (mean [SEM] expression, 3.01 [0.54]; P = .005), and infiltrative cSCC (mean [SD] expression, 2.01 [0.30]; P = .006) compared with normal skin specimens. In double-label immunofluorescence staining, CD11c+, a marker of myeloid dendritic cells, colocalized with PD-L1 and PD-L2 in cSCC lesions. Conclusions and Relevance: The favorable treatment response combined with significant involvement of PD-1 and PD ligands in cSCC lesions suggests that PD-1 blockade may be a viable therapeutic option for locally advanced cSCC and provides rationale for further investigation in future clinical trials.

Cutaneous squamous cell carcinomas (SCCs) account for up to 10,000 deaths annually in the United States. Most of the more than 700,000 SCCs diagnosed are cured by excision with clear margins; however, metastasis can occur despite seemingly adequate treatment in some cases. Immune-suppressed organ transplant recipients are 60 to 100 times more likely to develop SCC than immune-competent individuals. Transplant-associated SCCs occur more frequently and behave more aggressively, showing higher risk of recurrence and metastasis. This article identifies a potential role for interleukin-22 in driving SCC proliferation, particularly in solid organ transplant recipients taking cyclosporine.

Importance: Confocal microscopy has the potential to provide rapid bedside pathologic analysis, but clinical adoption has been limited in part by the need for physician retraining to interpret grayscale images. Digitally stained confocal mosaics (DSCMs) mimic the colors of routine histologic specimens and may increase adaptability of this technology. Objective: To evaluate the accuracy and precision of 3 physicians using DSCMs before and after training to detect basal cell carcinoma (BCC) and squamous cell carcinoma (SCC) in Mohs micrographic surgery fresh-tissue specimens. Design: This retrospective study used 133 DSCMs from 64 Mohs tissue excisions, which included clear margins, residual BCC, or residual SCC. Discarded tissue from Mohs surgical excisions from the dermatologic surgery units at Memorial Sloan Kettering Cancer Center and Oregon Health & Science University were collected for confocal imaging from 2006 to 2011. Final data analysis and interpretation took place between 2014 and 2016. Two Mohs surgeons and a Mohs fellow, who were blinded to the correlating gold standard frozen section diagnoses, independently reviewed the DSCMs for residual nonmelanoma skin cancer (NMSC) before and after a brief training session (about 5 minutes). The 2 assessments were separated by a 6-month washout period. Main Outcomes and Measures: Diagnostic accuracy was characterized by sensitivity and specificity of detecting NMSC using DSCMs vs standard frozen histopathologic specimens. The diagnostic precision was calculated based on interobserver agreement and kappa scores. Paired 2-sample t tests were used for comparative means analyses before and after training. Results: The average respective sensitivities and specificities of detecting NMSC were 90% (95% CI, 89%-91%) and 79% (95% CI, 52%-100%) before training and 99% (95% CI, 99%-99%) (P = .001) and 93% (95% CI, 90%-96%) (P = .18) after training; for BCC, they were 83% (95% CI, 59%-100%) and 92% (95% CI, 81%-100%) before training and 98% (95% CI, 98%-98%) (P = .18) and 97% (95% CI, 95%-100%) (P = .15) after training; for SCC, they were 73% (95% CI, 65%-81%) and 89% (95% CI, 72%-100%) before training and 100% (P = .004) and 98% (95% CI, 95%-100%) (P = .21) after training. The pretraining interobserver agreement was 72% (kappa = 0.58), and the posttraining interobserver agreement was 98% (kappa = 0.97) (P = .04). Conclusions and Relevance: Diagnostic use of DSCMs shows promising correlation to frozen histologic analysis, but image quality was affected by variations in image contrast and mosaic-stitching artifact. With training, physicians were able to read DSCMs with significantly improved accuracy and precision to detect NMSC.

Basal cell carcinoma (BCC) is the most common human cancer with an estimate of over one million new cases diagnosed in the United States every year. Treatment for BCC is largely achieved by surgical excision, but there are select cases of locally aggressive BCC where surgery may be complicated by severe functional and cosmetic compromise. Other therapeutic options include vismod-egib, an FDA-approved smoothened inhibitor for treating advanced BCC patients, or immune activation with imiquimod. These options, however, are not effective for all BCC patients. By combining laser capture microdissection and cDNA microarray techniques, we have previously established gene expression profiling of BCC tumor nests (localized and infiltrative) as well as normal epidermis. We have demonstrated that anaplastic lymphoma kinase (ALK) was highly expressed in BCC and could be a potential therapeutic option for treating BCC. In this study, we investigated the expression of additional receptor tyrosine kinases in BCC, in addition to ALK. cDNA microarray analysis identified increased expression of AXL (FCH = 4.30, p<10~⁴), DDR1 (FCH = 3.27, p<10~⁴), NTRK3 (FCH = 38.26, p<10~⁴), and TRIM27 (FCH = 4.39, p<10~⁴). Protein expression of these molecules within tissues was also evaluated by immunohistochemistry. Although further functional analysis is required to assess the suitability of these receptor tyrosine kinases as therapeutic targets for BCC, identification of previously unrecognized molecules will facilitate developing new therapeutic strategy

Cancer testis antigens (CTAs) are tumor-associated antigens selectively expressed in human tumors, but not in normal tissues except for testis and placenta. CTAs possess strong immunogenic-ity, thus can be suitable molecular targets for cancer immune therapy. Squamous cell carcinoma (SCC) is a second most common skincancer.Although manycasesarecurablebysurgical treatment, recent studies have shown that the death rate for SCC approaches that for melanoma in parts of the United States. By combining laser capture microdissection and cDNA microarray techniques, we have previously established gene expression profiling of three distinct transformed keratinocytic regions (actinic keratosis, in situ SCC, and invasive SCC) as well as normal epidermis. We found that CTAs such as, MAGEA3, MAGEA4, and MAGEA6 were selectively up-regulated in invasive SCC, but not in actinic keratosis or in situ SCC compared to normal epidermis (fold change <3.0 and false discovery rate >0.05). The specific expression of MAGEA3 in invasive SCC wasconfirmedbyreverse transcription polymerase chain reaction for messenger RNA. Protein expression within the tissues was then examined by immunohistochemistry. Identification of new therapeutic target will facilitate developing new therapeutic strategy. Although further functional analysis is required to assess the suitability of these CTAs as therapeutic targets for SCC, our preliminary results suggest that cutaneous SCC can be a potential target of cancer immune therapy

BACKGROUND: While infrequent, nodal metastases in cutaneous squamous cell carcinoma (cSCC) can result in death from disease. Identification of those at risk for metastases is key to improved prognostication and treatment. OBJECTIVE: To review metastatic cSCC at the study institution. METHODS AND MATERIALS: Sixteen patients with metastatic cSCC were identified at the New York University Dermatologic Associates and Cancer Associates from 1998 to 2013. Patients were staged with American Joint Committee on Cancer (AJCC) and modified Brigham and Women's Hospital (BWH) criteria and compared to 32 control subjects. RESULTS: Seven of 16 patients were identified as Stage T2 by AJCC criteria and Stage T2b by BWH criteria; two patients were on Stage T1, three patients were on more advanced T stages, and four patients lacked primary tumor data. Five patients had hematologic malignancy, and one patient had a solid-organ transplant. CONCLUSION: The modified BWH criteria aims to better prognosticate the large group of T2 AJCC tumors, resulting in the majority of mortality. In the experience of the authors, the majority of patients with metastatic disease were on T2, stratifying to stage T2b by BWH criteria, or more advanced T stages. The findings of this study support BWH stratification of T2 tumors and also indicate that hematologic malignancy is a significant comorbidity associated with a poor outcome.

Immune-suppressed organ transplant recipients (OTRs) can develop catastrophic squamous cell carcinoma (SCC), characterized by multiple primary tumors, extensive body surface area involvement, or metastases. There are currently no curative systemic therapies available. We previously showed that IL-22 enhances SCC proliferation. Herein, we examined links between cyclosporine (CSA), IL-22, and SCC in patients, cell lines, and mice with UV light-induced SCC. Eighteen of 114 OTRs developed catastrophic SCC, which was strongly associated with CSA treatment. We found that CSA drives T cell polarization toward IL-22-producing T22 cells, and CSA treatment increased IL-22 receptor in SCC cells. SCC tissue from OTRs showed increased expression of IL-22RA1. CSA potentiated rescue by IL-22 of serum-starved SCC cells; treatment of SCC cells with IL-22 and CSA increased both their migratory and invasive capacity. In a UV-induced model of SCC in SKH-1 immunocompetent mice, treatment with anti-IL-22 antibody reduced tumor number and tumor burden. We found that catastrophic SCC in OTRs is associated with CSA use, which may be acting by favoring T22 polarization. Since anti-IL-22 antibody administration decreased tumor number and tumor burden in vivo, blockade of the IL-22 axis may be developed as a viable therapeutic option for catastrophic SCC.