Faculty Bibliography

It is well established that immunosuppressed patients are at increased risk for poor outcomes (PO) from cutaneous squamous cell carcinoma (cSCC), including local recurrence (LR), nodal metastasis (NM), distant metastasis (DM), and disease-specific death (DSD). Defining PO risk is challenging but may be beneficial in guiding management. We aimed to define PO risk factors and evaluated their importance in immunosuppressed versus immunocompetent patients. We conducted a 4-year single-center retrospective review of patients with cSCC. Patient and tumor characteristics were evaluated in those that experienced PO. Immunosuppressed patients were ~ 11-fold more likely than immunocompetent patients to develop PO (10/85 vs. 15/1332, p < 0.0001). Among those with PO, immunosuppressed patients had diminished relapse free (p = 0.026) and progression free (p < 0.001) survival compared to immunocompetent. Immunosuppression was significantly associated with LR (p < 0.00001). Immunosuppressed patients were also more likely to develop NM, DM and experience DSD (p = 0.027). Mohs Appropriate Use Criteria was associated with NM, DM and DSD (p = 0.029), with area H tumors more likely to result in metastasis and death. In conclusion, immunosuppressed patients are more likely to develop LR, metastasis, and DSD from cSCC compared to immunocompetent patients. Immunosuppressed status was an independent risk factor for PO in this cohort and further considered for its inclusion in prognostication schema is warranted.

There is controversy regarding the optimal surgical modality and ideal recommended margins for treating melanoma in situ (MIS) and invasive melanoma (IM). Although wide local excision is recommended, staged excision offers excellent margin control and low recurrence rates. In this manuscript, we reviewed a 10-year experience of staged excisions for the treatment of MIS and IM. A retrospective review was performed of 130 MIS and 32 IM cases treated with staged excision from April 2012 to April 2022. Staged excision was performed on the head and neck in 102 (79%) MIS and 23 (72%) IM cases. Approximately 10% of cases required surgical margins above the current recommendations (11 (9%) MIS and 6 (19%) IM). Twenty-three (19%) MIS and 7 (22%) IM cases required more than one excision to obtain clearance. Recurrence rates among MIS and IM were 0.0% and 0.6%, respectively. Upstaging occurred in 5 (4%) MIS and 7 (22%) IM cases. Complex repairs were performed on 82 (63%) MIS and 17 (53%) IM cases. Our findings revealed that staged excision provides effective margin control and low recurrence rates. Approximately 10% of patients required margins greater than the current recommendations, leading to larger defects and more complex repairs.

INTRODUCTION/BACKGROUND:Nasal reconstruction has important functional and cosmetic considerations, as proper repair of nasal defects is necessary to maintain function of the nasal airway and to recreate the normal appearance of this central facial structure. Cheek advancement flaps provide matched, mobile and highly vascularized tissue for the reconstruction of nasal defects, allowing for the concealment of incisions within natural creases in a one-stage approach. However, cheek advancement flaps are often underutilized for nasal reconstruction because of their difficulty restoring nasal contour. METHODS:We describe reconstruction of 19 nasal dorsal and sidewall defects 0.8 to 3.0 centimeters (cm) in size. We incorporated a periosteal anchoring suture to maintain/restore nasal contour and additionally removed a half standing cone inferior to the defect to prevent encroachment of the nasal ala or alar crease. All patients were evaluated at least 3 months post-operatively. RESULTS:In all patients, we were able to restore concavity of the nasofacial sulcus, preserve the biconvex nasal tips, prevent alar flaring and retraction and conserve the alar groove. All patients had excellent functional and cosmetic outcomes. CONCLUSION/CONCLUSIONS:We believe this modified cheek advancement flap provides functionally and aesthetically superior results and can be considered as a first-line approach for repair of nasal dorsal and sidewall defects in sub selected patients.

Background/Purpose: The skin is recognized as a window into the immunopathogenic mechanisms driving the vast phenotypic spectrum of psoriatic disease.
Method(s): To better decipher the cellular landscape of both healthy and psoriatic skin, we employed spatial transcriptomics (ST), a ground-breaking technology that precisely maps gene expression from histologically-intact tissue sections (Fig. 1A).
Result(s): Findings gleaned from computationally integrating our 23 matched lesional and non-lesional psoriatic and 7 healthy control samples with publicly-available single-cell ribonucleic acid (RNA) sequencing datasets established the ability of ST to recapitulate the tissue architecture of both healthy and inflamed skin (Fig. 1B) and highlighted topographic shifts in the immune cell milieu, from a predominantly perifollicular distribution in steady-state skin to the papillary and upper reticular dermis in psoriatic lesional skin. We also incidentally discovered that ST's ability to ascertain gene expression patterns from intact tissue rendered it particularly conducive to studying the transcriptome of lipid-laden cells such as dermal adipose tissue and sebaceous glands (Fig. 1C), whose expression profiles are typically lost in the process of tissue handling and dissociation for bulk and single-cell RNA seq. Unbiased clustering of pooled healthy and psoriatic samples identified two epidermal clusters and one dermal cluster that were differentially expanded in psoriatic lesional skin (p values <=0.05) (Fig. 1D); pathway analysis of these clusters revealed enrichment of known psoriatic inflammatory pathways (Fig. 1E). Unsupervised classification of skin-limited psoriasis and psoriatic arthritis samples revealed stratification by cutaneous disease severity or Psoriasis Area and Severity Index (PASI) score and not by presence or absence of concomitant systemic/synovial disease (Fig. 1F). Remarkably, this PASI-dependent segregation was also evident in distal, non-lesional samples and was driven by the dermal macrophage and fibroblast cluster and the lymphatic endothelium (Fig. 2A). Inquiry into the mechanistic drivers of this observed stratification yielded enrichment of pathways associated with key T cell and innate immune cell activation, B cells, and metabolic dysfunction (Fig. 2B). Finally, tissue scale computational cartography of gene expression revealed differences in regional enrichment of specific cell types across phenotypic groups, most notably upward extension of fibroblasts to the upper dermis in both lesional and non-lesional samples from mild psoriasis and restriction to the lower dermis in the moderate-to-severe psoriasis samples (Fig. 2C), suggesting that disease severity stratification may be driven by emergent cellular ecosystems in the upper dermis. Fig. 1. (A) Schematic of spatial transcriptomics study workflow. Four mm skin punch biopsies were obtained from healthy volunteers (n=3) and lesional and non-lesional skin from patients with psoriatic disease (n=11). Ten micron-thick sections were then placed on capture areas on the ST microarray slide, each containing molecularly barcoded, spatially encoded spots with a diameter of 50 microns and a center-to-center distance of 100 microns. (B) Side-by-side comparison of a hematoxylin-eosin (H&E) stained section of representative healthy, lesional, and non-lesional skin samples and the corresponding ST plots showed concordance of unbiased gene expression-based clustering with histologic tissue architecture. (C) Pathway analysis of the adipose cluster in healthy skin (cluster 2) confirmed upregulation of lipid-associated processes. Inset: Spots corresponding to the adipose cluster highlighted in yellow. (D) Wilcoxon rank sum test (results displayed as box plots) yielded statistically significant expansion of three clusters in lesional skin compared to both non-lesional and healthy skin-inflamed suprabasal epidermis (cluster 4), epidermis 2 (cluster 7), and inflamed dermis (cluster 10). HC=healthy control, L=lesional psoriatic skin, NL=non-lesional psoriatic skin. (E) Pathways enriched in clusters 4, 7, and 10. (F) Principal component analysis (PCA) plots demonstrating segregation of samples by severity of cutaneous disease in both lesional and non-lesional samples along the first principal component (right) that was not seen in the samples categorized according to presence or absence of arthritis (left). PsA=psoriatic arthritis, PsO=skin-limited psoriasis. Fig. 2. (A) PCA of lesional and non-lesional samples colored by disease severity in spatial clusters 1 (left) and 12 (right) revealed more discrete clustering. (B) Pathways significantly enriched in clusters 1 (left) and 12 (right) showed enrichment of pathways associated with key T cell and innate immune cell activation, B cells, and metabolic dysfunction (highlighted in red). (C) SpaceFold one dimension projection of cell distribution from an independently-generated single-cell RNA seq data set on aggregated ST lesional and non-lesional samples from mild (PASI-low) and moderate-severe (PASI-high) samples. Y-axis represents tissue position, starting with the lower dermis marked as position 0 to suprabasal epidermis marked as position 1. Dashed line represents epidermal-dermal junction, discerned by cell types in the basal epidermal layer (melanocytes and Langerhans cells). Fibroblast signatures (red arrows) were largely relegated to the lower dermis in the PASI-high group, but extended to the upper dermis in the PASI-low group. This striking difference in fibroblast localization was also noted in non-lesional PASI-high vs. PASI-low groups. In addition to fibroblasts, lymphatic, endothelial, myeloid, and T cells signatures (black arrows) were also observed in the upper dermis of lesional PASI-low samples, but were much lower in the dermis of PASI-low non-lesional and all samples in the PASI-high group. Interfollicular epidermis (IFE), hair follicle and infundibulum (HF/IFN), n= number of individual biopsies.
Conclusion(s): Thus, we have been able to successfully leverage ST integrated with independently-generated single-cell RNA seq data to spatially define the emergent cellular ecosystems of healthy and matched psoriatic lesional and non-lesional skin and in so doing, demonstrated the value of ST in unearthing the genetic groundwork at both the site of inflammation and in distal, clinically-uninvolved skin

Background: Immune response is key in defense against basal cell carcinoma (BCC). We aim to better define the immune tumor microenvironment in this cancer.
Method(s): CD8+ tumor infiltrating lymphocytes (TILs) obtained from fresh BCC tumor specimens from nodular subtype ("nBCC", n=6) versus infiltrative subtype ("iBCC", n=6) were subject to single-cell RNA profiling. Data were analyzed using iCellR.
Result(s): CD8+ TILs were clustered based on gene expression as follows: cytotoxic (GZMA, GZMB, IFN-gamma, PRF1); naive (CCR7, LEF1, TCF7, IL7R, OX40); exhausted (BTLA, CTLA4, PDCD1, TIM3, LAG3, STAT3, 4-1BB); and regulatory (FOXP3, TIM3, OX40); additional subtypes were observed for naive, exhausted, and regulatory T cells. A significantly greater percentage of cytotoxic TILs and lesser percentage of naive TILs were observed in iBCC compared to nBCC. Further analysis revealed a unique, pro-tumor-controlling naive subtype in nBCC and a unique, highly suppressive regulatory subtype in iBCC; moreover, regulatory TILs in nBCC exclusively clustered in a low suppressive activity subtype. Additionally, percentage of all exhausted TILs was not significantly different across tumor subtype; however, there was a significantly greater proportion of pro-tumor-controlling progenitor exhausted and terminally exhausted TILs in nBCC.
Conclusion(s): Two significantly greater proportions of pro-tumor controlling exhausted subtypes and one significantly lower proportion of highly suppressive regulatory subtype were identified in nBCC compared to iBCC, possibly contributing to observed relative aggressiveness of these tumors. Additionally, more exhausted TILs from nBCC tended to cluster in a progenitor exhausted phenotype that may be more responsive to immune checkpoint blockade therapy.
Copyright

Background: The immune tumor microenvironment (TME) is key to controlling disease progression in skin cancer. We aim to compare the TME in these cancers to better inform prognosis and therapeutic decision making.
Method(s): CD8+ tumor infiltrating lymphocytes (TILs) obtained from fresh immunocompetent SCC (n=5) and BCC (n=12) tumors and solid-organ transplant recipient SCC ("TSCC", n=6) tumors were subject to single-cell RNA profiling. Data were analyzed using iCellR.
Result(s): CD8+ TILs were clustered based on gene expression: cytotoxic (GZMA, GZMB, IFN-gamma, PRF1); naive (CCR7, LEF1, TCF7, IL7R, OX40); exhausted (BTLA, CTLA4, PDCD1, TIM3, LAG3, STAT3, 4-1BB); and regulatory (FOXP3, TIM3, OX40); additional subtypes were observed for naive, exhausted, and regulatory T cells. Similar percentages of cytotoxic TILs were observed in SCC and BCC, significantly greater than in TSCC. Conversely, TSCC had the highest percentage of exhausted TILs. TSCC exhausted cells also tended to be more terminally exhausted, while those in SCC and BCC tended to be more progenitor exhausted. While the overall percentage of the regulatory CD8 compartment was similar across all three groups, SCC had a significantly greater proportion of a more suppressive subtype.
Conclusion(s): Many significant differences in the CD8 TME were observed between SCC, TSCC, and BCC. TSCC was associated with a proportionally larger and extensively terminally exhausted CD8 compartment. BCC was also associated with a significantly greater exhausted compartment than SCC, possibly correlating to the relatively slow-growing clinical course of BCC. Additionally, SCC was associated with a significantly greater proportion of more suppressive regulatory CD8s, possibly correlating to the greater clinical aggressiveness of SCC.
Copyright

Dermatomyositis (DM) is an autoimmune connective tissue disease that most commonly affects skin and muscles. Clinical manifestations can be protean, with some patients experiencing skin-limited disease while others develop serious systemic complications including interstitial lung disease (ILD). While both T cell-mediated and humoral immune dysregulation have been purported to play a role in manifesting said end-organ damage, our understanding of immunophenotypic prognostic factors associated with the development of ILD in DM patients remains limited. Thus, we sought to identify potential biomarkers that might be differentially expressed in lesional skin obtained from DM patients with versus without ILD. Utilizing NanoString technology, we assessed differential mRNA expression of 800 immune-related genes in formalin-fixed, paraffin-embedded lesional skin samples obtained from five DM patients with ILD compared to five DM patients without ILD. Among 42 highly regulated genes, 10 were significantly (p<0.05) upregulated in DM patients with ILD: CD44, NFKBIZ, CD24, EGR1, DEFB103B, CCL18, CCL22, CXCL2, S100A8 and S100A9. Notably, serum levels of S100A8/A9 heterodimer (an endogenous ligand of Toll-like receptor 4) are known to correlate with clinical severity in patients with DM-associated ILD, thereby supporting NanoString's utility in identifying salient genes associated with end-organ damage in DM. We also identified several novel genes downregulated in patients with DM-associated ILD that play a role in autophagy and adaptive immune activation: CLEC7, LEF1, KLRC2, BTLA, MUC1, and TCF7. Taken together, our results begin to characterize an immune-related gene expression signature in lesional DM skin that may be associated with comorbid ILD. While validation experiments are ongoing, the identification of biomarkers of systemic disease in lesional DM skin not only has the potential for risk stratifying DM patients at the time of tissue diagnosis but may provide novel targets for early intervention against DM-associated ILD.
Copyright