Noninvasive virtual biopsy using micro-registered optical coherence tomography (OCT) in human subjects

Histological hematoxylin and eosin-stained (H&E) tissue sections are used as the gold standard for pathologic detection of cancer, tumor margin detection, and disease diagnosis. Producing H&E sections, however, is invasive and time-consuming. While deep learning has shown promise in virtual staining of unstained tissue slides, true virtual biopsy requires staining of images taken from intact tissue. In this work, we developed a micron-accuracy coregistration method [micro-registered optical coherence tomography (OCT)] that can take a two-dimensional (2D) H&E slide and find the exact corresponding section in a 3D OCT image taken from the original fresh tissue. We trained a conditional generative adversarial network using the paired dataset and showed high-fidelity conversion of noninvasive OCT images to virtually stained H&E slices in both 2D and 3D. Applying these trained neural networks to in vivo OCT images should enable physicians to readily incorporate OCT imaging into their clinical practice, reducing the number of unnecessary biopsy procedures.

Skin basal cell carcinomas assemble a pro-tumorigenic spatially organized and self-propagating Trem2+ myeloid niche

Cancer immunotherapies have revolutionized treatment but have shown limited success as single-agent therapies highlighting the need to understand the origin, assembly, and dynamics of heterogeneous tumor immune niches. Here, we use single-cell and imaging-based spatial analysis to elucidate three microenvironmental neighborhoods surrounding the heterogeneous basal cell carcinoma tumor epithelia. Within the highly proliferative neighborhood, we find that TREM2+ skin cancer-associated macrophages (SCAMs) support the proliferation of a distinct tumor epithelial population through an immunosuppression-independent manner via oncostatin-M/JAK-STAT3 signaling. SCAMs represent a unique tumor-specific TREM2+ population defined by VCAM1 surface expression that is not found in normal homeostatic skin or during wound healing. Furthermore, SCAMs actively proliferate and self-propagate through multiple serial tumor passages, indicating long-term potential. The tumor rapidly drives SCAM differentiation, with intratumoral injections sufficient to instruct naive bone marrow-derived monocytes to polarize within days. This work provides mechanistic insights into direct tumor-immune niche dynamics independent of immunosuppression, providing the basis for potential combination tumor therapies.

Patient-Reported Nasal Function and Appearance After Interpolation Flap Repair Following Skin Cancer Resection: A Multicenter Prospective Cohort Study

Objective: Among patients undergoing two-stage interpolated flap repair of nasal defects, nasal function, and appearance before surgery and at 16 weeks after flap takedown were compared using the Nasal Appearance and Function Evaluation Questionnaire (NAFEQ). Design: Multicenter prospective cohort study. Methods: Adult patients with a nasal skin cancer anticipated to require two-stage interpolation flap repair completed the NAFEQ before surgery, at 1 week after flap placement, 4 weeks after flap takedown, and 16 weeks after flap takedown. Results: One hundred sixty-nine patients were enrolled, with 138 patients completing both presurgical and 16-week post-takedown NAFEQs. Overall NAFEQ score increased by 1.09 points (1.91% improvement, confidence interval [95% CI -0.34 to 2.53]). NAFEQ functional subscale increased by 0.72 points (2.58% increase; 95% CI [0.10-1.35]) and appearance subscale increased by 0.37 points (1.28% improvement, 95% CI [-0.65 to 1.39]). Conclusion: At 16 weeks after flap takedown, patients' perceptions of their nasal function and appearance are similar to or slightly improved when compared with their presurgical assessments.

Rapid Cellular-Resolution Skin Imaging with Optical Coherence Tomography Using All-Glass Multifocal Metasurfaces

Cellular-resolution optical coherence tomography (OCT) is a powerful tool offering noninvasive histology-like imaging. However, like other optical microscopy tools, a high numerical aperture (N.A.) lens is required to generate a tight focus, generating a narrow depth of field, which necessitates dynamic focusing and limiting the imaging speed. To overcome this limitation, we developed a metasurface platform that generates multiple axial foci, which multiplies the volumetric OCT imaging speed by offering several focal planes. This platform offers accurate and flexible control over the number, positions, and intensities of axial foci generated. All-glass metasurface optical elements 8 mm in diameter are fabricated from fused-silica wafers and implemented into our scanning OCT system. With a constant lateral resolution of 1.1 μm over all depths, the multifocal OCT triples the volumetric acquisition speed for dermatological imaging, while still clearly revealing features of stratum corneum, epidermal cells, and dermal-epidermal junctions and offering morphological information as diagnostic criteria for basal cell carcinoma. The imaging speed can be further improved in a sparse sample, e.g., 7-fold with a seven-foci beam. In summary, this work demonstrates the concept of metasurface-based multifocal OCT for rapid virtual biopsy, further providing insights for developing rapid volumetric imaging systems with high resolution and compact volume.

Single-cell analysis of human basal cell carcinoma reveals novel regulators of tumor growth and the tumor microenvironment

How basal cell carcinoma (BCC) interacts with its tumor microenvironment to promote growth is unclear. We use singe-cell RNA sequencing to define the human BCC ecosystem and discriminate between normal and malignant epithelial cells. We identify spatial biomarkers of tumors and their surrounding stroma that reinforce the heterogeneity of each tissue type. Combining pseudotime, RNA velocity-PAGA, cellular entropy, and regulon analysis in stromal cells reveals a cancer-specific rewiring of fibroblasts, where STAT1, TGF-β, and inflammatory signals induce a noncanonical WNT5A program that maintains the stromal inflammatory state. Cell-cell communication modeling suggests that tumors respond to the sudden burst of fibroblast-specific inflammatory signaling pathways by producing heat shock proteins, whose expression we validated in situ. Last, dose-dependent treatment with an HSP70 inhibitor suppresses in vitro vismodegib-resistant BCC cell growth, Hedgehog signaling, and in vivo tumor growth in a BCC mouse model, validating HSP70's essential role in tumor growth and reinforcing the critical nature of tumor microenvironment cross-talk in BCC progression.

c-FOS drives reversible basal to squamous cell carcinoma transition

While squamous transdifferentiation within subpopulations of adenocarcinomas represents an important drug resistance problem, its underlying mechanism remains poorly understood. Here, using surface markers of resistant basal cell carcinomas (BCCs) and patient single-cell and bulk transcriptomic data, we uncover the dynamic roadmap of basal to squamous cell carcinoma transition (BST). Experimentally induced BST identifies activator protein 1 (AP-1) family members in regulating tumor plasticity, and we show that c-FOS plays a central role in BST by regulating the accessibility of distinct AP-1 regulatory elements. Remarkably, despite prominent changes in cell morphology and BST marker expression, we show using inducible model systems that c-FOS-mediated BST demonstrates reversibility. Blocking EGFR pathway activation after c-FOS induction partially reverts BST in vitro and prevents BST features in both mouse models and human tumors. Thus, by identifying the molecular basis of BST, our work reveals a therapeutic opportunity targeting plasticity as a mechanism of tumor resistance.

Patient Quality of Life After Interpolated Flap Repair of Nasal Mohs Surgery Defects: A Multicenter Prospective Cohort Study

Importance

Single-center studies have shown that patients report better skin cancer-specific quality of life (QOL) after Mohs micrographic surgery (MMS), but it is unclear whether this improved QOL applies to patients after MMS and complex reconstruction in cosmetically sensitive areas.

Objective

To evaluate patient QOL after MMS and interpolation flap reconstruction for patients with nasal skin cancers.

Design, Setting and Participants

This multicenter prospective survey study used the Skin Cancer Index (SCI), a validated, 15-question QOL questionnaire administered at 4 time points: before MMS, 1 week after flap placement, 4 weeks after flap takedown, and 16 weeks after flap takedown. Patients age 18 years or older with a nasal skin cancer who presented for MMS and were anticipated to undergo 2-stage interpolated flap repair by a Mohs surgeon were recruited from August 9, 2018, to February 2, 2020, at 8 outpatient MMS locations across the United States, including both academic centers and private practices.

Main Outcomes and Measures

Mean difference in overall SCI score before MMS vs 16 weeks after flap takedown.

Results

A total of 169 patients (92 men [54.4%]; mean [SD] age, 67.7 [11.4] years) were enrolled, with 147 patients (75 men [51.0%]; mean [SD] age, 67.8 [11.7] years) completing SCI surveys both before MMS and 16 weeks after flap takedown. Total SCI scores improved significantly 16 weeks after flap takedown compared with pre-MMS scores, increasing by a mean of 13% (increase of 7.11 points; 95% CI, 5.48-8.76; P < .001). All 3 SCI subscale scores (emotion, appearance, and social) improved significantly (emotion subscale, increase of 3.27 points; 95% CI, 2.35-4.18; P < .001; appearance subscale, increase of 1.65 points; 95% CI, 1.12-2.18; P < .001; and social subscale, increase of 2.10 points; 95% CI, 1.55-2.84; P < .001) 16 weeks after flap takedown compared with pre-MMS.

Conclusions and Relevance

Removal of a nasal skin cancer and repair of the resulting defect can be distressing for patients. However, this cohort study suggests that physicians referring patients for MMS can be reassured that their patient's QOL will improve on average after surgery, even when a complex reconstruction is required.

Systematic review and meta-analysis of local recurrence rates of head and neck cutaneous melanomas after wide local excision, Mohs micrographic surgery, or staged excision

BACKGROUND

Prospective trials have not compared the local recurrence rates of different excision techniques for cutaneous melanomas on the head and neck.

OBJECTIVE

To determine local recurrence rates of cutaneous head and neck melanoma after wide local excision (WLE), Mohs micrographic surgery (MMS), or staged excision.

METHODS

A systematic review of PubMed, EMBASE, and Web of Science identified all English case series, cohort studies, and randomized controlled trials that reported local recurrence rates after surgery for cutaneous head and neck melanoma. A meta-analysis utilizing a random effects model calculated weighted local recurrence rates and confidence intervals (CI) for each surgical technique and for subgroups of MMS and staged excision.

RESULTS

Among 100 manuscripts with 13,998 head and neck cutaneous melanomas, 51.0% (7138) of melanomas were treated by WLE, 34.5% (4826) by MMS, and 14.5% (2034) by staged excision. Local recurrence rates were lowest for MMS (0.61%; 95% CI, 0.1%-1.4%), followed by staged excision (1.8%; 95% CI, 1.0%-2.9%) and WLE (7.8%; 95% CI, 6.4%-9.3%).

LIMITATIONS

Definitions of local recurrence varied. Surgical techniques included varying proportions of invasive melanomas. Studies had heterogeneity.

CONCLUSION

Systematic review and meta-analysis show lower local recurrence rates for cutaneous head and neck melanoma after treatment with MMS or staged excision compared to WLE.

Frequent basal cell cancer development is a clinical marker for inherited cancer susceptibility

Innate DNA repair mechanisms play a critical role in protecting skin keratinocytes from UV mutagenesis and skin cancer development. We hypothesized that individuals who develop frequent skin cancers may harbor germline defects in DNA repair genes and have increased predisposition to internal malignancies. We enrolled 61 patients with unusually frequent basal cell carcinoma (BCC) development, seen at Stanford Hospital and Clinics from January 2005 until December 2015, for germline analysis of 29 DNA repair genes. In parallel, a case-control retrospective review was performed to interrogate the association of malignancies with frequent BCC development in a large US medical insurance claims database (Truven), which included 13,264 individuals with 6 or more BCCs from 2007 to 2011. 19.7% of the frequent BCC cohort harbored pathogenic mutations in DNA repair genes: APC, BARD1, BRCA1, BRCA2, CDH1, CHEK2, MLH1, MSH2, MSH6, MUTYH, NBN, and PALB2. Individuals with 6 or more BCCs had an increased risk of other malignancies, with a 3.5-fold increase in the frequent BCC cohort and a 3.2-fold increase in the Truven database. Individuals who developed frequent BCCs have an increased prevalence of germline mutations in DNA repair genes and increased malignancy risk. Our data implicate frequent BCC development as an external marker of inherited cancer risk.

Idiopathic eruptive macular pigmentation: a case of 21 years' duration

Idiopathic eruptive macular pigmentation is a rare condition characterized by asymptomatic pigmented macules involving the neck, trunk, and proximal portions of the extremities. Age at onset usually varies from 1 to 20 years. The lesions usually appear abruptly and remit spontaneously over months to years. An unusual case of a 24-year-old woman with idiopathic eruptive macular pigmentation lasting 21 years was characterized by several periods of spontaneous resolution followed by recurrences.

Autoantibodies to type VII collagen have heterogeneous subclass and light chain compositions and their complement-activating capacities do not correlate with the inflammatory clinical phenotype

Epidermolysis bullosa acquisita and bullous systemic lupus erythematosus are blistering skin diseases characterized by IgG autoantibodies that predominantly target the noncollagenous domain 1 of type VII collagen, a skin basement membrane component. The basic immunologic events leading to the blistering processes in these diseases remains unclear. We defined the subclass and light chain compositions of the IgG autoantibodies in 15 patients, in order to gain insight into the blistering mechanism. Immunofluorescence correlated the patients' in vivo-bound and circulating antibasement membrane autoantibodies. Four eukaryotic recombinant proteins, including one full-length and three truncated noncollagenous domain 1 proteins generated by sequential deletion of C-terminal amino acids, were used to perform enzyme-linked immunosorbent assay to detect the patients' anti-type VII collagen autoantibodies. The majority of patients' autoantibodies contained both complement-activating and non-complement-activating IgG subclasses. The presence or absence of complement-activating IgG autoantibody subclasses did not correlate with the inflammatory or noninflammatory clinical phenotype. The majority of tested sera contained both kappa and lambda light chain autoantibodies. All sera that reacted to the full-length noncollagenous domain 1 also reacted to the smallest truncated protein containing the cartilage matrix protein and the first three fibronectinlike repeats. The patients' anti-type VII collagen autoantibodies, likely to be polyclonal in nature, may contribute to the pathogenesis of the blistering process by both complement-dependent inflammatory injury and complement-independent mechanical disruption of the anchoring function of type VII collagen. The N-terminal region of the noncollagenous domain 1 may contain an important antigenic epitope targeted by the IgG autoantibodies.

Successful correction of depressed scars of the forehead secondary to trauma and morphea en coup de sabre by en bloc autologous dermal fat graft

BACKGROUND

Atrophic scars of the forehead can result from various pathologic processes including morphea en coup de sabre as well as trauma. A variety of surgical techniques can be used to correct these atrophic scars.

OBJECTIVE

Soft tissue augmentation for correction of atrophic scars of the forehead using en bloc autologous dermal fat graft.

METHODS

Use of en bloc autologous dermal fat graft harvested from the hip and inserted into a pocket created under the atrophic scar in two patients with depressed scars of the forehead.

RESULTS

Overcorrection of the scars with en bloc autologous dermal fat grafts resulted in the treated areas becoming level with the adjacent skin within 3 months. Follow-up for a period of 12 months showed a perfectly level and stable graft with no further resorption.

CONCLUSION

En bloc autologous dermal fat grafting appears to be a safe technique that provides excellent cosmetic results for the correction of small to medium depressed scars of the forehead.