The Impact of Next-generation Sequencing on Interobserver Agreement and Diagnostic Accuracy of Desmoplastic Melanocytic Neoplasms

Next-generation sequencing (NGS) is increasingly being utilized as an ancillary tool for diagnostically challenging melanocytic neoplasms. It is incumbent upon the pathology community to perform studies assessing the benefits and limitations of these tools in specific diagnostic scenarios. One of the most challenging diagnostic scenarios faced by skin pathologists involves accurate diagnosis of desmoplastic melanocytic neoplasms (DMNs). In this study, 20 expert melanoma pathologists rendered a diagnosis on 47 DMNs based on hematoxylin and eosin sections with demographic information. After submitting their diagnosis, the experts were given the same cases, but this time with comprehensive genomic sequencing results, and asked to render a diagnosis again. Identification of desmoplastic melanoma (DM) improved by 7%, and this difference was statistically significant ( P <0.05). In addition, among the 15 melanoma cases, in the pregenomic assessment, only 12 were favored to be DM by the experts, while after genomics, this improved to 14 of the cases being favored to be DM. In fact, some cases resulting in metastatic disease had a substantial increase in the number of experts recognizing them as DM after genomics. The impact of the genomic findings was less dramatic among benign and intermediate-grade desmoplastic tumors (BIDTs). Interobserver agreement also improved, with the Fleiss multirater Kappa being 0.36 before genomics to 0.4 after genomics. NGS has the potential to improve diagnostic accuracy in the assessment of desmoplastic melanocytic tumors. The degree of improvement will be most substantial among pathologists with some background and experience in bioinformatics and melanoma genetics.

Cutaneous crystal storing histiocytosis: A case series with review of literature

Crystal-storing histiocytosis (CSH) is a rare condition in which crystals accumulate in the cytoplasm of histiocytes and is usually associated with a lymphoplasmacytic neoplasm. Cutaneous CSH is extraordinarily rare and limited to case reports in the literature. We report two cases of this disease with cutaneous involvement. Case 1 was a 65-year-old male with a 4-month history of a pruritic eruption that started as a solitary pink to skin-colored indurated plaque on the anterior neck before progressing to involve the whole neck, chest wall, and face. Case 2 was a 54-year-old woman with a history of unspecified "lymphoma" who presented with a soft nodule on the forearm. Biopsies from both cases had similar findings and showed a proliferation of epithelioid cells with pink cytoplasm and intracellular crystalline structures infiltrating the dermis and subcutaneous fat. In the first case, the cells were positive for CD43, CD45, CD68, and IgG kappa, and in the second case, the crystals were positive for IgG lambda. Based on these findings, the patients were diagnosed with cutaneous CSH. We highlight this rare diagnosis and the importance of investigating an underlying lymphoplasmacytic neoplasm.

Autologous human preclinical modeling of melanoma interpatient clinical responses to immunotherapeutics

BACKGROUND

Despite recent advances in immunotherapy, a substantial population of late-stage melanoma patients still fail to achieve sustained clinical benefit. Lack of translational preclinical models continues to be a major challenge in the field of immunotherapy; thus, more optimized translational models could strongly influence clinical trial development. To address this unmet need, we designed a preclinical model reflecting the heterogeneity in melanoma patients' clinical responses that can be used to evaluate novel immunotherapies and synergistic combinatorial treatment strategies. Using our all-autologous humanized melanoma mouse model, we examined the efficacy of a novel engineered interleukin 2 (IL-2)-based cytokine variant immunotherapy.

METHODS

To study immune responses and antitumor efficacy for human melanoma tumors, we developed an all-autologous humanized melanoma mouse model using clinically annotated, matched patient tumor cells and peripheral blood mononuclear cells (PBMCs). After inoculating immunodeficient NSG mice with patient tumors and an adoptive cell transfer of autologous PBMCs, mice were treated with anti-PD-1, a novel investigational engineered IL-2-based cytokine (nemvaleukin), or recombinant human IL-2 (rhIL-2). The pharmacodynamic effects and antitumor efficacy of these treatments were then evaluated. We used tumor cells and autologous PBMCs from patients with varying immunotherapy responses to both model the diversity of immunotherapy efficacy observed in the clinical setting and to recapitulate the heterogeneous nature of melanoma.

RESULTS

Our model exhibited long-term survival of engrafted human PBMCs without developing graft-versus-host disease. Administration of an anti-PD-1 or nemvaleukin elicited antitumor responses in our model that were patient-specific and were found to parallel clinical responsiveness to checkpoint inhibitors. An evaluation of nemvaleukin-treated mice demonstrated increased tumor-infiltrating CD4+ and CD8+ T cells, preferential expansion of non-regulatory T cell subsets in the spleen, and significant delays in tumor growth compared with vehicle-treated controls or mice treated with rhIL-2.

CONCLUSIONS

Our model reproduces differential effects of immunotherapy in melanoma patients, capturing the inherent heterogeneity in clinical responses. Taken together, these data demonstrate our model's translatability for novel immunotherapies in melanoma patients. The data are also supportive for the continued clinical investigation of nemvaleukin as a novel immunotherapeutic for the treatment of melanoma.

MED15::ATF1-Rearranged Tumor: A Novel Cutaneous Tumor With Melanocytic Differentiation

We recently described novel dermal tumors with melanocytic differentiation and morphologic and biological similarities to cutaneous clear cell sarcoma, including CRTC1::TRIM11 cutaneous tumor, and clear cell tumors with melanocytic differentiation and either ACTIN::MITF or MITF::CREM. Here, we describe a series of 3 patients presenting with tumors reminiscent of CRTC1::TRIM11 cutaneous tumor, found to demonstrate a novel MED15::ATF1 fusion. All 3 patients were children (5-16 years old). Primary excision of case 1 showed a circumscribed wedge-shaped silhouette with peripheral intercalation into collagen fibers and scattered lymphoid aggregates. All 3 tumors abutted the epidermis; one showed a junctional component. Tumors were highly cellular and comprised of monomorphic, oval-to-round epithelioid cells arranged in vague nests and short fascicles in variably fibrotic stroma. Mitotic rate was high (hotspot 6-12/mm2), without atypical mitoses. Necrosis was focally present in case 3. All cases showed strong, diffuse nuclear staining for SOX10 and MITF (2/2) but showed variable expression for S100 protein (1/3) and other melanocytic markers-Melan-A (focal in 2/3), HMB45 (focal in 1/3), and Pan-Melanoma (patchy in 1/1). Whole-exome RNA sequencing demonstrated a MED15::ATF1 fusion without any other notable alterations. Cases 1 and 2 were completely excised without recurrence (12 months). Case 3 developed a grossly apparent regional lymph node spread shortly after primary biopsy. The patient was treated with wide excision, radiation, cervical lymph node dissection (4/46 with >75% lymph node replacement), and neoadjuvant and adjuvant nivolumab (alive without disease at cycle 11). This series is presented to aid in future diagnosis of this novel dermal tumor with melanocytic differentiation and emphasize the potential for aggressive biologic behavior, which should be considered in patient management planning.

Phase II Clinical Trial of Pembrolizumab and Chemotherapy Reveals Distinct Transcriptomic Profiles by Radiologic Response in Metastatic Triple-Negative Breast Cancer

PURPOSE

A single arm, phase II trial of carboplatin, nab-paclitaxel, and pembrolizumab (CNP) in metastatic triple-negative breast cancer (mTNBC) was designed to evaluate overall response rate (ORR), progression-free survival (PFS), duration of response (DOR), safety/tolerability, overall survival (OS), and identify pathologic and transcriptomic correlates of response to therapy.

PATIENTS AND METHODS

Patients with ≤2 prior therapies for metastatic disease were treated with CNP regardless of tumor programmed cell death-ligand 1 status. Core tissue biopsies were obtained prior to treatment initiation. ORR was assessed using a binomial distribution. Survival was analyzed via the Kaplan-Meier method. Bulk RNA sequencing was employed for correlative studies.

RESULTS

Thirty patients were enrolled. The ORR was 48.0%: 2 (7%) complete responses (CR), 11 (41%) partial responses (PR), and 8 (30%) stable disease (SD). The median DOR for patients with CR or PR was 6.4 months [95% confidence interval (CI), 4-8.5 months]. For patients with CR, DOR was >24 months. Overall median PFS and OS were 5.8 (95% CI, 4.7-8.5 months) and 13.4 months (8.9-17.3 months), respectively. We identified unique transcriptomic landscapes associated with each RECIST category of radiographic treatment response. In CR and durable PR, IGHG1 expression was enriched. IGHG1high tumors were associated with improved OS (P = 0.045) and were concurrently enriched with B cells and follicular helper T cells, indicating IGHG1 as a promising marker for lymphocytic infiltration and robust response to chemo-immunotherapy.

CONCLUSIONS

Pretreatment tissue sampling in mTNBC treated with CNP reveals transcriptomic signatures that may predict radiographic responses to chemo-immunotherapy.

Subcutaneous Leiomyosarcoma: An Aggressive Malignancy Portending a Significant Risk of Metastasis and Death

Subcutaneous leiomyosarcoma (LMS) is a rare, poorly understood variant. The current literature on the subject is sparse, consisting of isolated case reports and small clinicopathologic studies compromised by the inclusion of both its more common and indolent counterpart, cutaneous LMS (atypical intradermal smooth muscle neoplasm), as well as highly aggressive deep-seated tumors. Thus, precise clinicopathologic characterization is limited. Cases of subcutaneous LMS reviewed at the University of Michigan and Cleveland Clinic from 1994 to 2022 were included in this retrospective study. A total of 39 cases were identified. The mean age was 61 years, and the cohort was predominantly male (23/39; 59%). Tumors averaged 4.2 cm and most commonly arose on the extremities (32/39; 82%). The majority (38/39; 97%) were diagnosed at an early pathologic stage (pT1 or pT2). Histopathologically, most tumors were well-circumscribed and were assigned a Fédération Nationale des Centers de Lutte Contre le Cancer grade of either 1 or 2 (24/39; 62%). The majority (22/39; 56%) appeared to arise in association with a blood vessel. Of the 36 cases with accessible clinical data and follow-up (mean 34 mo, range 0 to 94 mo), 12 (33%) were noted to have metastasized, with the lung representing the most common anatomic location. One case recurred locally. Six of 36 patients (17%) died from the disease at an average of 47 months after diagnosis (range 16 to 94 mo). Metastasis or death from disease was significantly associated with the Fédération Nationale des Centers de Lutte Contre le Cancer grade ( P =0.0015), the presence of necrosis ( P =0.032), tumor size ( P =0.049), and AJCC tumor stage ( P =0.036). These data demonstrate that subcutaneous LMS are more aggressive than dermal-based tumors and have a prognosis akin to that of deep-seated LMS.

Keratin-positive giant cell-rich tumors of soft tissue with HMGA2::NCOR2 fusions

BACKGROUND

Giant cell tumor of soft tissue (GCT-ST) is a rare soft tissue neoplasm that is morphologically similar to but genetically distinct from giant cell tumor of bone. A novel keratin-positive GCT-ST (KPGCT-ST) harboring HMGA2::NCOR2 fusions was recently discovered. Fewer than 30 cases have been described; herein is reported an additional seven.

METHODS

Cases diagnosed as GCT-ST were retrieved from institutional archives and consultation files. The histopathologic characteristics were assessed, and the electronic medical record was reviewed.

RESULTS

Seven tumors were identified in six women and one man with a median age of 23 years. All patients underwent excision; no recurrences or metastases were noted during a median follow-up period of 7 months. Histopathologically, the tumors were characterized by a multinodular proliferation of keratin-positive mononuclear cells with evenly admixed osteoclast-like giant cells and absent neoplastic bone. A fibrous capsule with lymphoid cuffing was frequently seen. Foamy macrophages, inflammation, hemorrhage, and hemosiderin were variably present. The HMGA2::NCOR2 fusion was detected in all cases.

CONCLUSIONS

Our findings support previously reported hypotheses that KPGCT-ST is a spectrum of the same entity as the recently described xanthogranulomatous epithelial tumor. Although follow-up data are limited, to date, KPGCT-ST appears to follow an indolent course.

Intra-host mutation rate of acute SARS-CoV-2 infection during the initial pandemic wave

SARS-CoV-2 mutation is minimized through a proofreading function encoded by NSP-14. Most estimates of the SARS-CoV-2 mutation rate are derived from population based sequence data. Our understanding of SARS-CoV-2 evolution might be enhanced through analysis of intra-host viral mutation rates in specific populations. Viral genome analysis was performed between paired samples and mutations quantified at allele frequencies (AF) ≥ 0.25, ≥ 0.5 and ≥ 0.75. Mutation rate was determined employing F81 and JC69 evolution models and compared between isolates with (ΔNSP-14) and without (wtNSP-14) non-synonymous mutations in NSP-14 and by patient comorbidity. Forty paired samples with median interval of 13 days [IQR 8.5-20] were analyzed. The estimated mutation rate by F81 modeling was 93.6 (95%CI 90.8-96.4], 40.7 (95%CI 38.9-42.6) and 34.7 (95%CI 33.0-36.4) substitutions/genome/year at AF ≥ 0.25, ≥ 0.5, ≥ 0.75 respectively. Mutation rate in ΔNSP-14 were significantly elevated at AF ≥ 0.25 vs wtNSP-14. Patients with immune comorbidities had higher mutation rate at all allele frequencies. Intra-host SARS-CoV-2 mutation rates are substantially higher than those reported through population analysis. Virus strains with altered NSP-14 have accelerated mutation rate at low AF. Immunosuppressed patients have elevated mutation rate at all AF. Understanding intra-host virus evolution will aid in current and future pandemic modeling.

Nipple Adenoma: Clinicopathologic Characterization of 50 Cases

Nipple adenoma (NA) is a rare, benign proliferation of the nipple ducts. It may be clinically mistaken for Paget disease or squamous cell carcinoma; thus, microscopic evaluation is paramount. A large case series of NA has not been undertaken since the 1980s. Therefore, we undertook this study to evaluate the clinicopathologic characteristics of NA, emphasizing differential diagnoses and follow-up data. We retrieved 50 cases from our in-house archives or consultation files between 2003 and 2022. Available slides were reviewed, and clinical data and follow-up information were obtained. Cases must have exhibited a dense ductal proliferation in the breast tissue with proximity to the nipple epidermis. All patients were women; median age was 56 years. In all, 68% of patients were symptomatic; 53% demonstrated a skin growth. Overall, 67% were excised completely, either primarily (33%) or via re-excision after biopsy (33%). Four histologic patterns were noted: adenosis (dense proliferation of small-to-medium ducts); large duct (medium-to-large caliber ducts); papillary-like (frond-like architecture with branching, slit-like lumens); and pseudoinfiltrative (ducts squished and distorted by dense stromal fibrosis). Follow-up in 44 patients (88%) with a median time of 66 months showed no evidence of recurrence. NA demonstrates a wide spectrum of histopathologic variation. Subtyping of this entity is unlikely to be clinically relevant. Differentiation from invasive carcinoma or other histologic mimics (syringocystadenoma papilliferum, syringomatous adenoma) may be difficult. Simple excision is curative, and recurrence is rare. A definitive link to invasive carcinoma has not been established.

Primary cutaneous extraskeletal osteosarcoma: a series of 16 cases

Extraskeletal osteosarcoma (EOS) is a high grade soft tissue tumour characterised by the production of malignant osteoid, without attachment/involvement of underlying bone/periosteum. Rarely, EOS presents as a cutaneous tumour. The clinical behaviour of primary cutaneous EOS (PC-EOS) remains incompletely characterised. Herein we present the largest case series of PC-EOS reported to date. Sixteen PC-EOS cases from the archives/consultation files were retrieved (male:female 1:1; age 31-96 years, mean age 66 years). The tumours measured 1-10 cm (mean 3.2 cm) and were located on the lower extremity (7), head (6), upper extremity (2), and trunk (1). They consisted of pleomorphic, spindled-to-epithelioid cells, with fascicular, nodular, or sheet-like growth patterns and foci of malignant osteoid. Immunohistochemistry did not reveal specific lines of differentiation, and there was no evidence of other tumour types. A literature review was conducted to identify all well characterised cases of PC-EOS. A combined analysis of present and past cases was performed to determine overall trends in clinical characteristics and outcomes. The mean follow-up period was 23.9 months, during which 67.5% of patients experienced progression-free survival and 18% of patients died of disease. Rates of local recurrence and metastasis were 10% and 25%, respectively, approximately double past estimates. These data suggest that the prognosis of PC-EOS is less favourable than previously thought. The differential diagnosis includes benign entities (e.g., ossifying pyogenic granuloma) and malignant neoplasms with heterologous osteosarcomatous differentiation (e.g., carcinosarcoma, transdifferentiated melanoma). Wide excision remains the standard of care, and the role of chemotherapy and radiation remains inconclusive. Recognition of this rare entity can facilitate prompt diagnosis and appropriate treatment.

The capillary lobule variant of radiation-associated angiosarcoma in the setting of breast cancer: A diagnostic pitfall

AIM

Post-radiation angiosarcoma is an iatrogenic event seen in the setting of breast cancer treatment. Histopathologically, there are morphologic variants of angiosarcoma that mimic benign entities, including the capillary lobule variant of post-radiation angiosarcoma. We present the largest case series to date of this histopathologic variant of post-radiation angiosarcoma.

METHODS AND RESULTS

Cases of the capillary lobule variant of post-radiation angiosarcoma from institutional/consultation archives from 2008 to June 2022 were reviewed. For inclusion, tumors had to occur in irradiated skin and exhibit a multi-lobular proliferation of tightly packed capillary-like vessels, as previously described in this variant. Prior ancillary studies were also reviewed. Eight cases met the criteria. All occurred in women treated with radiation for breast cancer (median age 75 years). All cases had similar findings, including a multi-lobular proliferation of tightly packed vessels, infiltrative cords, and atypical single endothelial cells. A conventional angiosarcoma pattern was also seen in five cases. All cases tested were positive for vascular markers (CD31, CD34, and/or ERG) and MYC. MYC amplification was shown by FISH in all cases tested. Smooth muscle actin (SMA) was positive in pericytes in the capillary lobules in all five cases tested and areas of conventional angiosarcoma in two of three cases.

CONCLUSIONS

The capillary lobule variant of angiosarcoma is a rare and therefore potentially under-recognized variant of post-radiation angiosarcoma. The lobular architecture and SMA positivity may mimic benign vascular proliferations. Careful attention to histopathologic features and ancillary tests may facilitate accurate diagnosis.

Combined utility of p16 and BRAF V600E in the evaluation of spitzoid tumors: Superiority to PRAME and correlation with FISH

BACKGROUND

Spitzoid melanocytic neoplasms are diagnostically challenging; criteria for malignancy continue to evolve. The ability to predict chromosomal abnormalities with immunohistochemistry (IHC) could help select cases requiring chromosomal evaluation.

METHODS

Fluorescence in situ hybridization (FISH)-tested spitzoid neoplasms at our institution (2013-2021) were reviewed. p16, BRAF V600E, and preferentially expressed antigen in melanoma (PRAME) IHC results were correlated with FISH.

RESULTS

A total of 174 cases (1.9F:1M, median age 28 years; range, 5 months-74 years) were included; final diagnoses: Spitz nevus (11%), atypical Spitz tumor (47%), spitzoid dysplastic nevus (9%), and spitzoid melanoma (32%). Sixty (34%) were FISH positive, most commonly with absolute 6p25 gain (RREB1 > 2). Dermal mitotic count was the only clinicopathologic predictor of FISH. Among IHC-stained cases, p16 was lost in 55 of 134 cases (41%); loss correlated with FISH positive (p < 0.001, Fisher exact test). BRAF V600E (14/88, 16%) and PRAME (15/56, 27%) expression did not correlate with FISH alone (p = 0.242 and p = 0.359, respectively, Fisher exact test). When examined together, however, p16-retained/BRAF V600E-negative lesions had low FISH-positive rates (5/37, 14%; 4/37, 11% not counting isolated MYB loss); all other marker combinations had high rates (56%-75% of cases; p < 0.001).

CONCLUSIONS

p16/BRAF V600E IHC predicts FISH results. "Low-risk" lesions (p16⁺ /BRAF V600E^- ) uncommonly have meaningful FISH abnormalities (11%). PRAME may have limited utility in this setting.

Rhabdomyosarcoma Arising in an Old Rhytidectomy Scar

OBJECTIVE

The clinical evaluation and management of an adult with head and neck rhabdomyosarcoma is explored to delineate the diagnostic challenge posed by soft-tissue sarcomas bordering scar tissue.

CASE REPORT

A 59 year old female presents with persistent, evolving paresthesia and burning in the right posterior neck, which was found to be in close proximity to a well-healed rhytidectomy scar. Serial biopsies were non-diagnostic. Six months after initial presentation, rhabdomyosarcoma was diagnosed subsequent to histopathological and immunohistochemistry analysis. A wide local excision with posterolateral neck dissection was performed.

CONCLUSION

A high index of suspicion for soft-tissue sarcoma should be maintained for patients with persistent soft-tissue lesions, especially in areas of scarred tissue, who present with new-onset neurological symptoms in the context of nondiagnostic biopsies.

Superficial low-grade fibromyxoid sarcoma

BACKGROUND

Low-grade fibromyxoid sarcoma (LGFMS) typically involves deep soft tissue (beneath the fascia) of the proximal extremities and trunk. Long-term follow-up has shown a high rate of local recurrence, metastasis, and death. To the best of our knowledge, there is only one previous large series focusing on superficial LGFMS suggesting superficial tumors are disproportionately more common in children and may have a better prognosis. Our study's primary goals are to confirm these findings and increase general awareness that LGFMS may arise in superficial soft tissue.

METHODS

We retrieved our cases of superficial LGFMS diagnosed between 2008 and 2020. Available slides were reviewed, and clinical data and follow-up information were obtained.

RESULTS

The patients included nine males and 14 females with a median age of 29 years; eight (35%) were children (<18 years) and five (22%) were young adults (18-30 years). The majority involved the lower extremities (65%). The tumors were primarily centered in the subcutis (91%) and dermis (9%). Microscopically, they had typical features of LGFMS with alternating fibrous and myxoid zones composed of bland, slightly hyperchromatic spindled cells. All were positive for MUC4 by immunohistochemistry and/or FUS rearrangement by FISH. Follow-up on 14 cases ranged from 11 to 148 months (median 61 months) with no evidence of recurrences or distant metastases.

CONCLUSIONS

Compared to conventional deep-seated counterparts, superficial LGFMS is more likely to occur in the extremities of children and young adults and may have a better clinical outcome. Further studies with longer follow-up will likely help support these findings.

InterMEL: An international biorepository and clinical database to uncover predictors of survival in early-stage melanoma

INTRODUCTION

We are conducting a multicenter study to identify classifiers predictive of disease-specific survival in patients with primary melanomas. Here we delineate the unique aspects, challenges, and best practices for optimizing a study of generally small-sized pigmented tumor samples including primary melanomas of at least 1.05mm from AJTCC TNM stage IIA-IIID patients. We also evaluated tissue-derived predictors of extracted nucleic acids' quality and success in downstream testing. This ongoing study will target 1,000 melanomas within the international InterMEL consortium.

METHODS

Following a pre-established protocol, participating centers ship formalin-fixed paraffin embedded (FFPE) tissue sections to Memorial Sloan Kettering Cancer Center for the centralized handling, dermatopathology review and histology-guided coextraction of RNA and DNA. Samples are distributed for evaluation of somatic mutations using next gen sequencing (NGS) with the MSK-IMPACTTM assay, methylation-profiling (Infinium MethylationEPIC arrays), and miRNA expression (Nanostring nCounter Human v3 miRNA Expression Assay).

RESULTS

Sufficient material was obtained for screening of miRNA expression in 683/685 (99%) eligible melanomas, methylation in 467 (68%), and somatic mutations in 560 (82%). In 446/685 (65%) cases, aliquots of RNA/DNA were sufficient for testing with all three platforms. Among samples evaluated by the time of this analysis, the mean NGS coverage was 249x, 59 (18.6%) samples had coverage below 100x, and 41/414 (10%) failed methylation QC due to low intensity probes or insufficient Meta-Mixed Interquartile (BMIQ)- and single sample (ss)- Noob normalizations. Six of 683 RNAs (1%) failed Nanostring QC due to the low proportion of probes above the minimum threshold. Age of the FFPE tissue blocks (p<0.001) and time elapsed from sectioning to co-extraction (p = 0.002) were associated with methylation screening failures. Melanin reduced the ability to amplify fragments of 200bp or greater (absent/lightly pigmented vs heavily pigmented, p<0.003). Conversely, heavily pigmented tumors rendered greater amounts of RNA (p<0.001), and of RNA above 200 nucleotides (p<0.001).

CONCLUSION

Our experience with many archival tissues demonstrates that with careful management of tissue processing and quality control it is possible to conduct multi-omic studies in a complex multi-institutional setting for investigations involving minute quantities of FFPE tumors, as in studies of early-stage melanoma. The study describes, for the first time, the optimal strategy for obtaining archival and limited tumor tissue, the characteristics of the nucleic acids co-extracted from a unique cell lysate, and success rate in downstream applications. In addition, our findings provide an estimate of the anticipated attrition that will guide other large multicenter research and consortia.

Alpha to Omicron: Disease Severity and Clinical Outcomes of Major SARS-CoV-2 Variants

Background

Four severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) variants predominated in the United States since 2021. Understanding disease severity related to different SARS-CoV-2 variants remains limited.

Method

Viral genome analysis was performed on SARS-CoV-2 clinical isolates circulating March 2021 through March 2022 in Cleveland, Ohio. Major variants were correlated with disease severity and patient outcomes.

Results

In total 2779 patients identified with either Alpha (n = 1153), Gamma (n = 122), Delta (n = 808), or Omicron variants (n = 696) were selected for analysis. No difference in frequency of hospitalization, intensive care unit (ICU) admission, and death were found among Alpha, Gamma, and Delta variants. However, patients with Omicron infection were significantly less likely to be admitted to the hospital, require oxygen, or admission to the ICU (χ2 = 12.8, P &lt; .001; χ2 = 21.6, P &lt; .002; χ2 = 9.6, P = .01, respectively). In patients whose vaccination status was known, a substantial number had breakthrough infections with Delta or Omicron variants (218/808 [26.9%] and 513/696 [73.7%], respectively). In breakthrough infections, hospitalization rate was similar regardless of variant by multivariate analysis. No difference in disease severity was identified between Omicron subvariants BA.1 and BA.2.

Conclusions

Disease severity associated with Alpha, Gamma, and Delta variants is comparable while Omicron infections are significantly less severe. Breakthrough disease is significantly more common in patients with Omicron infection.

Alpha to Omicron: Disease Severity and Clinical Outcomes of Major SARS-CoV-2 Variants

BACKGROUND

Four severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) variants predominated in the United States since 2021. Understanding disease severity related to different SARS-CoV-2 variants remains limited.

METHOD

Viral genome analysis was performed on SARS-CoV-2 clinical isolates circulating March 2021 through March 2022 in Cleveland, Ohio. Major variants were correlated with disease severity and patient outcomes.

RESULTS

In total 2779 patients identified with either Alpha (n 1153), Gamma (n 122), Delta (n 808), or Omicron variants (n 696) were selected for analysis. No difference in frequency of hospitalization, intensive care unit (ICU) admission, and death were found among Alpha, Gamma, and Delta variants. However, patients with Omicron infection were significantly less likely to be admitted to the hospital, require oxygen, or admission to the ICU (2 12.8, P .001; 2 21.6, P .002; 2 9.6, P .01, respectively). In patients whose vaccination status was known, a substantial number had breakthrough infections with Delta or Omicron variants (218/808 [26.9] and 513/696 [73.7], respectively). In breakthrough infections, hospitalization rate was similar regardless of variant by multivariate analysis. No difference in disease severity was identified between Omicron subvariants BA.1 and BA.2.

CONCLUSIONS

Disease severity associated with Alpha, Gamma, and Delta variants is comparable while Omicron infections are significantly less severe. Breakthrough disease is significantly more common in patients with Omicron infection.

Calciphylaxis in uraemic and nonuraemic settings: clinical risk factors and histopathological findings

BACKGROUND

Calciphylaxis is a life-threatening cutaneous ulcerative/necrotic disease characterized by vascular calcification/occlusion. It occurs most commonly in end-stage kidney disease (ESKD), known as uraemic calciphylaxis (UC) but can also occur in patients with chronic kidney disease (CKD) and normal kidney function (nonuraemic calciphylaxis; NUC). There are few large series of NUC in the literature.

AIM

To compare the clinicopathological features of UC and NUC.

METHODS

We retrospectively compared the clinicopathological features of 35 patients with NUC during the period 2010-2020 with those of 53 patients with UC (control group). Cases were classified as NUC in the absence of all of the following: ESKD, significant CKD (defined as serum creatinine > 3 mg/dL or creatinine clearance < 15 mL/min) and acute kidney injury requiring kidney replacement therapy or kidney transplantation.

RESULTS

NUC represented 40% of the total cases, and there was a higher number of women (P < 0.01) and a higher median body mass index (P = 0.06) compared with the control UC group. Elevated parathyroid hormone was present in 44% of patients with NUC. Most of the tested patients were positive for lupus anticoagulants (56%). NUC biopsies showed a higher rate of extravascular calcium deposits (73% vs. 47%, P = 0.03). Dermal reactive vascular proliferation was the most common dermal change (32%).

CONCLUSIONS

NUC is more common than previously reported and shows a higher predilection for obese postmenopausal women. Undiagnosed hyperparathyroidism shows a possible association with NUC. Lupus anticoagulants were positive in most patients. NUC biopsies are more likely than UC biopsies to display extravascular calcium deposition.

The clinicopathologic spectrum and genomic landscape of de-/trans-differentiated melanoma

Dedifferentiation and transdifferentiation are rare and only poorly understood phenomena in cutaneous melanoma. To study this disease more comprehensively we have retrieved 11 primary cutaneous melanomas from our pathology archives showing biphasic features characterized by a conventional melanoma and additional areas of de-/trans-differentiation as defined by a lack of immunohistochemical expression of all conventional melanocytic markers (S-100 protein, SOX10, Melan-A, and HMB-45). The clinical, histologic, and immunohistochemical findings were recorded and follow-up was obtained. The patients were mostly elderly (median: 81 years; range: 42-86 years) without significant gender predilection, and the sun-exposed skin of the head and neck area was most commonly affected. The tumors were deeply invasive with a mean depth of 7 mm (range: 4-80 mm). The dedifferentiated component showed atypical fibroxanthoma-like features in the majority of cases (7), while additional rhabdomyosarcomatous and epithelial transdifferentiation was noted histologically and/or immunohistochemically in two tumors each. The background conventional melanoma component was of desmoplastic (4), superficial spreading (3), nodular (2), lentigo maligna (1), or spindle cell (1) types. For the seven patients with available follow-up data (median follow-up period of 25 months; range: 8-36 months), two died from their disease, and three developed metastases. Next-generation sequencing of the cohort revealed somatic mutations of established melanoma drivers including mainly NF1 mutations (5) in the conventional component, which was also detected in the corresponding de-/trans-differentiated component. In summary, the diagnosis of primary cutaneous de-/trans-differentiated melanoma is challenging and depends on the morphologic identification of conventional melanoma. Molecular analysis is diagnostically helpful as the mutated gene profile is shared between the conventional and de-/trans-differentiated components. Importantly, de-/trans-differentiation does not appear to confer a more aggressive behavior.

Preferentially expressed antigen in melanoma and p16 expression in acral melanocytic neoplasms

Acral melanocytic neoplasms often pose diagnostic difficulty. Preferentially expressed antigen in melanoma (PRAME) expression and loss of p16 expression have diagnostic utility in melanocytic tumors. We examined PRAME and p16 expression in 30 acral melanocytic neoplasms (n = 11 nevi; n = 2 dysplastic nevi; n = 7 Spitz nevi; n = 10 acral melanomas). PRAME was scored as % positive nuclei: negative = 0%; 1% to 25% = 1+; 25% to 50% = 2+; 50% to 75% = 3+, or positive: 75% to 100% = 4+. p16 expression was defined as retained (homogeneous or checkerboard) or lost (complete or partial/regionally). PRAME expression was negative in all benign, dysplastic, and Spitz nevi. Conversely, all acral melanomas were diffusely (4+) positive for PRAME expression. p16 expression was retained in all benign acral nevi (8/11 homogeneous, 3/11 checkerboard), completely lost in one dysplastic nevus, and retained in all acral Spitz nevi (3/7 homogeneous, 4/7 checkerboard). p16 was retained in five of 10 acral melanomas (3/10 homogeneous; 2/10 checkerboard), and negative in five of 10 acral melanomas (absent in 3/10, partially lost in 2/10). Our data suggest that 4+ PRAME expression is highly sensitive and specific in the setting of acral melanomas and is a more predictive diagnostic tool compared with p16 immunohistochemistry.

Superficial ALK-rearranged myxoid spindle cell neoplasm: a cutaneous soft tissue tumor with distinctive morphology and immunophenotypic profile

Gene rearrangements involving the anaplastic lymphoma kinase (ALK) receptor tyrosine kinase gene have been identified in various neoplasms, including inflammatory myofibroblastic tumor and epithelioid fibrous histiocytoma. We present an ALK-rearranged cutaneous soft tissue tumor with unique morphologic and immunophenotypic features that are not shared by other entities with ALK rearrangements. The six cases involved two females and four males, aged 18-84 (mean 51) years old. Three tumors were on the back and three on the lower extremities (thigh, knee, shin); ranging from 0.5 to 5.6 (mean 2.1) cm. Four were confined to the dermis; two involved the subcutis. All six cases were characterized by the presence of spindled to ovoid cells arranged in concentric whorls and cords against a myxoid to myxohyaline stroma and relatively cellular aggregates of plump ovoid to epithelioid cells. Four cases showed distinct hyalinized blood vessels. Both cases that involved the subcutis showed peripheral lipofibromatosis-like areas. Tumor-infiltrating lymphocytes were absent to moderate. Severe cytologic atypia or conspicuous mitotic activity was not identified. Immunohistochemically, all tumors diffusely expressed ALK (D5F3) and CD34. All but one tumor was diffusely positive for S100 protein. All tumors were negative for EMA, AE1/AE3, SMA, and SOX10. Next-generation sequencing revealed ALK fusions with FLNA (3 cases), MYH10 (2 cases), and HMBOX1 (1 case) as the partner genes. In all six cases, the breakpoints involved exon 20 of ALK, which preserves the receptor tyrosine kinase domains of ALK in the fusion product. Of the four cases with limited follow-up information (2-18 months), none recurred. In conclusion, we report an ALK-rearranged cutaneous soft tissue tumor characterized by the presence of myxoid spindle cell whorls and cords, and co-expression of ALK, CD34, and frequently S100 protein, we term "superficial ALK-rearranged myxoid spindle cell neoplasm".

Cutaneous symplastic hemangioma: A series of four cases

Symplastic hemangiomas (SH) are benign vascular lesions that show atypia in vascular smooth muscle and interstitial cells with sparing of endothelial cells. We present four cases of this rare tumor. The patients (two males; two females) ranged in age from 57 to 83 years (median 74); lesions were located on the leg (n = 3) and back (n = 1), and ranged from 6 to 8 mm. SH were well-circumscribed and dermal-based, often with an epidermal collarette (3/4). They were characterized by the presence of variably atypical, hyperchromatic/pleomorphic epithelioid to spindled cells within vascular walls (3/4) and/or perivascular stroma (4/4). Atypical multinucleated cells were present in three of four cases. The overall mitotic rate was low (0-2 mitotic figures per 10 HPFs; mean 0.75 per 10 HPFs), but atypical mitotic figures were seen in two of four cases. Atypical cells were negative for SMA (0/2), desmin (0/2), AE1/3 (0/2), and CAM5.2 (0/1). ERG, CD31, and CD34 stains were positive in endothelial cells but negative in atypical cells (4/4). Lesional cells and vessels were negative for podoplanin (3/3). Symplastic hemangioma is a benign tumor with bizarre atypia that may be mistaken for malignancy. We present four cases of this rare entity to increase awareness of this tumor and discuss the differential diagnosis.

Update on Cutaneous Soft Tissue Tumors

This article focuses on various recently described or emerging cutaneous soft tissue neoplasms. These entities encompass a wide range of clinical and histologic characteristics. Emphasis is placed on their distinguishing morphologic and immunophenotypic features compared with entities that enter into their differential diagnosis, as well as novel immunophenotypic and molecular tests that are often necessary for accurate diagnosis of these entities. Entities discussed include EWSR1-SMAD3-rearranged fibroblastic tumor, superficial CD34-positive fibroblastic tumor, epithelioid fibrous histiocytoma, CIC-rearranged sarcomas, and NTRK-rearranged spindle cell tumors.

Genomic Epidemiology of SARS-CoV-2 Infection During the Initial Pandemic Wave and Association With Disease Severity

Importance

Understanding of SARS-CoV-2 variants that alter disease outcomes are important for clinical risk stratification and may provide important clues to the complex virus-host relationship.

Objective

To examine the association of identified SARS-CoV-2 variants, virus clades, and clade groups with disease severity and patient outcomes.

Design, Setting, and Participants

In this cross-sectional study, viral genome analysis of clinical specimens obtained from patients at the Cleveland Clinic infected with SARS-CoV-2 during the initial wave of infection (March 11 to April 22, 2020) was performed. Identified variants were matched with clinical outcomes. Data analysis was performed from April to July 2020.

Main Outcomes and Measures

Hospitalization, intensive care unit (ICU) admission, mortality, and laboratory outcomes were matched with SARS-CoV-2 variants.

Results

Specimens sent for viral genome sequencing originated from 302 patients with SARS-CoV-2 infection (median [interquartile range] age, 52.6 [22.8 to 82.5] years), of whom 126 (41.7%) were male, 195 (64.6%) were White, 91 (30.1%) required hospitalization, 35 (11.6%) needed ICU admission, and 17 (5.6%) died. From these specimens, 2531 variants (484 of which were unique) were identified. Six different SARS-CoV-2 clades initially circulated followed by a rapid reduction in clade diversity. Several variants were associated with lower hospitalization rate, and those containing 23403A>G (D614G Spike) were associated with increased survival when the patient was hospitalized (64 of 74 patients [86.5%] vs 10 of 17 patients [58.8%]; χ21 = 6.907; P = .009). Hospitalization and ICU admission were similar regardless of clade. Infection with Clade V variants demonstrated higher creatinine levels (median [interquartile range], 2.6 [-0.4 to 5.5] mg/dL vs 1.0 [0.2 to 2.2] mg/dL; mean creatinine difference, 2.9 mg/dL [95% CI, 0.8 to 5.0 mg/dL]; Kruskal-Wallis P = .005) and higher overall mortality rates (3 of 14 patients [21.4%] vs 17 of 302 patients [5.6%]; χ21 = 5.640; P = .02) compared with other variants. Infection by strains lacking the 23403A>G variant showed higher mortality in multivariable analysis (odds ratio [OR], 22.4; 95% CI, 0.6 to 5.6; P = .01). Increased variants of open reading frame (ORF) 3a were associated with decreased hospitalization frequency (OR, 0.4; 95% CI, 0.2 to 0.96; P = .04), whereas increased variants of Spike (OR, 0.01; 95% CI, <0.01 to 0.3; P = .01) and ORF8 (OR, 0.03; 95% CI, <0.01 to 0.6; P = .03) were associated with increased survival.

Conclusions and Relevance

Within weeks of SARS-CoV-2 circulation, a profound shift toward 23403A>G (D614G) specific genotypes occurred. Replaced clades were associated with worse clinical outcomes, including mortality. These findings help explain persistent hospitalization yet decreasing mortality as the pandemic progresses. SARS-CoV-2 clade assignment is an important factor that may aid in estimating patient outcomes.

Perineuriomatous nevi: A series of eight cases highlighting unifying pathologic features to avoid misdiagnosis

BACKGROUND

Perineuriomatous nevi are rare and diagnostically problematic. We report a series of eight perineuriomatous nevi to highlight the diagnostic features.

METHODS

Cases were retrospectively reviewed and characterized.

RESULTS

Median age was 42.5 years (range 25-64), with equal sex distribution. Lesions occurred on the arm (n = 4), trunk (n = 2), and head/neck (n = 2). Median size was 7.5 mm (range 5-12 mm). Clinical differential diagnoses included atypical nevus (3), blue nevus (1), neurofibroma (1), and dermatofibroma (1). Lesions were circumscribed, dome-shaped (5/8), and biphasic (8/8) with nested epithelioid cells and wavy spindled cells arranged in whorled fascicles in a myxocollagenous stroma. When present, junctional growth was lentiginous (4/8). No cases displayed pleomorphism or mitotic figures. The perineuriomatous component stained positively for epithelial membrane antigen (8/8 focal to diffuse) and CD34 (4/5 focal to diffuse). SOX10 and S100 protein stained all nevoid cells and in some cases a subset of intermingled spindled cells in perineuriomatous areas, where other melanocytic markers were negative. p16 protein expression was uniformly retained (3/3), and p53 negative (0/2). Nevoid cells in most lesions were positive for BRAFV600E (5/7). Ki67 was mildly elevated (~5%) in 3/3 cases.

CONCLUSIONS

Recognizing the histopathologic and immunophenotypic features in these unusual nevi helps avoid overdiagnosis.

Disease Progression in Cutaneous Squamous Cell Carcinoma Patients With Satellitosis and In-transit Metastasis

BACKGROUND/AIM

Satellitosis/in-transit metastasis (S-ITM) has prognostic value in melanoma and Merkel cell carcinoma, but is not incorporated into cutaneous squamous cell carcinoma (cSCC) staging.

PATIENTS AND METHODS

From our IRB-approved registry, patients with high-risk cSCC, including patients with S-ITM, were identified. Univariate (UVA) and multivariate (MVA) analyses were performed to compare disease progression (DP) and overall survival (OS). Cumulative incidence of DP and OS analyses were performed using Fine-Gray and Kaplan-Meier methods, respectively.

RESULTS

A total of 18 S-ITM subjects were compared to 247 high risk subjects including T3N0 (n=143), N1-N3 without extranodal extension (ENE) (n=56), N1-N3 with ENE (n=26) and M1 disease (n=22). Median follow up was 16.5 months. Three-year rates of DP were 22% for T3N0, 42% for S-ITM, 48% for T4 bone invasion, 50% for N1-N3 without extranodal extension (ENE), 53% for N1-N3 with ENE, and 66% for M1. Patients with S-ITM did not experience significantly worse DP compared to those with T3N0 (HR=1.96, 95%CI=0.8-4.9; p=0.14).

CONCLUSION

Cutaneous SCC patients with S-ITM experienced outcomes similar to locally advanced non-metastatic cSCC patients. Larger studies are needed to guide incorporation into staging systems.

EWSR1-SMAD3 rearranged fibroblastic tumor: Case series and review

We report the largest series to date (N = 6) of EWSR1-SMAD3 rearranged fibroblastic tumor. Initially described in 2018, the tumor features a marked female predominance (F:M, 5:1, mean age 44-years, median age 45.5 years; range 27-57), with most cases (5/6, 83%) arising in acral locations (4 on foot/toe, 1 on hand). One case presented on the lower extremity. The lesions presented as nodules and were composed of short, variably cellular, intersecting fascicles of uniform spindled cells in a collagenous to myxoid stroma. In four cases, the tumor abutted the epidermis without a grenz zone. In one case, there was an abrupt transition to a central, acellular hyalinized area. Two other cases had admixed smaller collagenous areas, reminiscent of collagen rosettes. One had a concentric arrangement of tumor cells around blood vessels. Mitotic activity was low (<1/10 HPFs). All were positive for ERG by immunohistochemistry and negative for CD34 (6/6). An EWSR1-SMAD3 fusion was identified in three cases tested by next-generation sequencing (3/3). Rearrangement of EWSR1 by fluorescence in situ hybridization was showed in 1/1 case. Our series reaffirms prior findings and expands the known histopathologic spectrum of this emerging entity.

p16 Range of expression in dermal predominant benign epithelioid and spindled nevi and melanoma

BACKGROUND

Screening borderline Spitz tumors with p16 immunohistochemistry (IHC) has known utility. The applicability to other melanocytic neoplasms is not well defined.

METHODS

Cases (N = 104) of blue, cellular blue, epithelioid blue, congenital pattern, deep penetrating, desmoplastic, desmoplastic Spitz, acral, "epithelioid" nevi, nevoid melanoma, melanoma with a precursor nevus, and non-nevoid melanoma with Breslow thickness > 0.5 mm were stained for p16.

RESULTS

Lesions showed either a single uniform pattern of expression (single/homogeneous pattern: positive, checkerboard, rare, or lost) or multiple regionally distributed patterns (multiple/heterogeneous pattern). Most cases (78%, n = 81) showed single pattern expression. Within single pattern cases, total loss was restricted to melanoma (7/81/9%). Multiple patterns were more common in melanoma (12/23, 52%). Within multiple pattern (22%, n = 23) lesions, those with a total loss component (7/23; 30%) were malignant. Total p16 loss (diffuse or regional) was not seen in a subset of nevoid melanomas (1/8; 12.5%), melanomas arising in nevi (2/6; 33%), and non-nevoid melanomas (6/9; 66%). Total p16 loss (single pattern or part of multiple patterns) captured 61% (14/23) of melanomas and no nevi.

CONCLUSION

p16 IHC may be useful in dermal-based melanocytic lesions. Total p16 loss is seen only in melanoma. Multiple pattern expression should prompt careful evaluation.

Targeted next generation sequencing (NGS) to classify melanocytic neoplasms

This study piloted a pan-solid-tumor next generation sequence (NGS)-based laboratory developed test as a diagnostic aid in melanocytic tumors. 31 cases (4 "epithelioid" nevi, 5 blue nevi variants, 7 Spitz tumors [3 benign and 4 malignant] and 15 melanomas) were evaluated. All tumors [median diameter 7 mm (range 4-15 mm); median thickness 2.25 mm (range 0.25-12 mm)] yielded satisfactory results. The number of small nucleotide variants/tumor was significantly different between melanoma (median 18/tumor, range 4-71) and all other lesions (median 8/tumor, range 3-17) (P < 0.004) and malignant (median 16/tumor, range 4-71) vs benign lesions (median 7/tumor, range 3-14) (P = 0.01). BRAF, MET, NTRK1, and ROS fusions only occurred in benign Spitz tumors; EML4 fusion, BRAF, MAP2K1 and TERT mutations occurred in malignant Spitz tumors and/or melanoma. Amplifications and NRAS and NF1 mutations only occurred in melanoma. Most melanomas contained >1 pathogenic alteration. Developed NGS-based criteria correctly classified all malignant lesions in this series. 10/12 cases showed concordance with FISH; consensus diagnosis agreed with NGS classification in FISH-non-concordant cases. This pilot study suggests that NGS may be an effective diagnostic adjunct comparable to FISH, but further studies with larger numbers of cases are needed.

A phase II trial of nivolumab in combination with talazoparib in unresectable or metastatic melanoma patients with mutations in BRCA or BRCAness

TPS10082

Background: Melanoma has a response rate of 10-15% with anti-PD-1 re-challenge in the refractory setting. Newer targeted therapies in melanoma are needed, especially once patients progress on immune checkpoint inhibitor (ICI) therapy. Analysis of TCGA and the Cleveland Clinic’s Gross Family Melanoma Registry reveals that a significant proportion (~40%) of melanoma patients possess somatic (31.6%) or germline (TCGA: 4.2%; Registry: 8.3%) mutations in homologous recombination repair genes, which may serve as a therapeutic target. PARP inhibitors, specifically talazoparib, have demonstrated synthetic lethality, potent PARP trapping activity, and increased immunogenicity of tumor cells by promoting T cell and NK cell infiltration in vitro and in vivo. Moreover, augmentation of the STING pathway via PARP inhibition modulates the tumor microenvironment, impacting PD-L1 expression and type I interferon production. Therefore, the use of talazoparib in combination with the ICI, nivolumab, may have a synergistic immunomodulatory and antitumor effect. Methods: This phase II, single arm, open label trial aims to enroll 37 primary or recurrent unresectable or metastatic melanoma patients harboring a somatic or germline mutation or deletion in BRCA or BRCAness (genes including ARID1A/B/2, ATM, ATR, BAP1, BARD1, BLM, BRCA1/2, BRIP1, CDK4/12, CHEK1/2, DSS1, EMSY, ERCC3, FANCA/D2, HDAC2, IDH1, LIG3/4, MDC1, MLH1/3, MRE11, NBN, PALB2, PRKDC, RAD50/51/54, XRCC6) who have progressed on prior ICI therapy. Patients will be treated with nivolumab 480mg IV every 4 weeks and talazoparib 1mg PO daily. The primary objective is to determine clinical efficacy of the combination therapy, as measured by the objective response rate. The trial is designed to test the null hypothesis that ORR ≤ 10% and is powered to detect an effect size of ORR ≥ 30%. Secondary objectives include PFS, OS, immune-related objective response rate (irORR), irPFS, and treatment-related adverse events. Associations with clinical response will be assessed with correlative studies of PD-L1 expression, ctDNA, tumor mutational burden, copy number variation, and the phenotypic and functional characterization of circulating and tumor infiltrating immune cells. The study is currently open and enrolling patients. Clinical trial information: NCT04187833.

Real-world experience of talimogene laherparepvec in patients receiving immunotherapy in metastatic melanoma

e22003

Background: Talimogene laherparepvec (TVEC) is an oncolytic herpes virus approved by the FDA for intralesional therapy in unresectable metastatic melanoma. However, little is known regarding the effectiveness of TVEC+checkpoint inhibition (CPI) outside of clinical trials. We present outcomes of the largest single institution experience with TVEC in the context of different immune checkpoint inhibitors. Methods: All patients with stage III-IV unresectable melanoma having received TVEC were evaluated. Patient demographics, clinicopathological characteristics, TVEC treatment response and outcomes were assessed. Final analysis included those who received TVEC adjacent to CPI with a minimum 6-month follow-up, excluding patients on clinical trials. Response was estimated by sequential measurement of injectable on-target lesions. Results: A total of 62 patients received TVEC from 2016 to 2019, of which 43 remained excluding Merkel cell carcinoma, patients on trials, and TVEC monotherapy. Of 30 patients with available treatment response data and at least 6-months follow-up, median age was 68.5 years (30-99 years), 40% were female, 16 (53.3%) stage IV. Median follow-up was 17.5 months (6-43 months). At 6 months, 20 (67.7%) patients were alive; at 1 year, 17 (56.7%) patients were alive. Eighteen patients received pembrolizumab, 7 nivolumab and 5 ipilimumab/nivolumab. Median number of TVEC doses received was 8 (3-31 doses). Median time on TVEC therapy was 4 months (1-26 months). Overall response rate for on-target lesions was 24 (80%), with complete local response (CR) in 15 (50%), partial response (PR) in 9 (30%), and progressive disease (PD) in 6 (20%). Median time to response was 6 weeks (2-17 weeks); 5 in CR, 6.5 in PR and 5.5 in PD groups. Adverse events were mostly mild and limited to constitutional symptoms. Conclusions: To our knowledge this is the largest real-world experience assessing TVEC in patients receiving CPI. Local overall response rate appears higher in comparison to historic numbers for TVEC monotherapy. The findings demonstrate that TVEC is an effective and safe treatment for metastatic melanoma and has robust outcomes in real-life clinical settings.

Superficial sarcomas with CIC rearrangement are aggressive neoplasms: A series of eight cases

CIC rearranged sarcomas have significant overlap with Ewing sarcoma, are aggressive, and typically present in deep soft tissue. They most commonly have a t(4;19)(q35;q13) with CIC-DUX4 fusion. Superficial presentation is rare. We report eight (6F, 2M; median 45-years-old, range 14-65) superficial CIC-rearranged sarcomas, involving the extremities (n = 4), vulva (n = 2), and trunk (n = 2). The tumors were composed of nodules/sheets of round cells with necrosis and hemorrhage separated by dense hyaline bands. Tumor cells had vesicular chromatin, prominent nucleoli and frequent mitotic figures. One showed pagetoid spread. Targeted next-generation sequencing was positive for CIC-DUX4 fusion (6/6); fluorescence in situ hybridization (FISH) was positive for CIC rearrangement (2/3). Eight of eight had evidence of CIC-DUX4 fusion/rearrangement by molecular techniques. Immunohistochemistry was positive for CD99+ (8/8) and DUX4+ (4/4). FISH for EWSR1 rearrangement was negative (5/5). Of five patients with at least 6 months follow-up, three of five died of disease, all within 2 years of presentation. One is alive with disease at 48 months. One is disease free at 3 months. Superficial CIC-rearranged sarcomas should be considered in cases exhibiting features reminiscent of Ewing sarcoma, but with increased pleomorphism and/or geographic necrosis. In contrast to superficial Ewing sarcomas, superficial CIC-rearranged sarcomas are aggressive.

Diagnoses of hospitalized patients with skin abnormalities prompting biopsy by consulting dermatologists: A 3-year review from a tertiary care center

Background

Dermatologists play an important role in diagnosing and managing hospitalized patients with cutaneous abnormalities. Skin biopsies remain an indispensable tool for aiding dermatologists in accurate diagnosis and treatment. We aimed to determine the range of conditions, and the most common conditions, prompting skin biopsy by dermatology hospital consultation (HCON) services to aid in evaluation of hospitalized patients.

Methods

All hospitalized patients seen by a single tertiary care center dermatology HCON service between 2015 and 2018 who had associated skin biopsies were identified. Histologic features and clinical diagnoses of each patient were classified into 13 histologic reaction pattern categories.

Results

Eight hundred and thirty one inpatients evaluated by our dermatology HCON service had 914 skin biopsies. The most frequent diagnostic categories prompting biopsy were vasculopathic (17.6%), interface dermatitis (16.5%), infectious (12.6%), and spongiotic dermatitis (10.9%). The most frequent diagnostic categories included drug reaction (13.2%), leukocytoclastic vasculitis (8.5%), skin cancer (5.4%), graft‐vs‐host disease (3.5%), connective tissue disease (3.3%), and calciphylaxis (3.0%).

Conclusion

Our study suggests a variety of serious diseases affecting inpatients prompts biopsy by dermatology consultation services. Educational curricula for dermatology and pathology residents, fellows, and staff designed with these data may enhance knowledge that improves the quality of inpatient dermatology care.

ALPK1 hotspot mutation as a driver of human spiradenoma and spiradenocarcinoma

Spiradenoma and cylindroma are distinctive skin adnexal tumors with sweat gland differentiation and potential for malignant transformation and aggressive behaviour. We present the genomic analysis of 75 samples from 57 representative patients including 15 cylindromas, 17 spiradenomas, 2 cylindroma-spiradenoma hybrid tumors, and 24 low- and high-grade spiradenocarcinoma cases, together with morphologically benign precursor regions of these cancers. We reveal somatic or germline alterations of the CYLD gene in 15/15 cylindromas and 5/17 spiradenomas, yet only 2/24 spiradenocarcinomas. Notably, we find a recurrent missense mutation in the kinase domain of the ALPK1 gene in spiradenomas and spiradenocarcinomas, which is mutually exclusive from mutation of CYLD and can activate the NF-κB pathway in reporter assays. In addition, we show that high-grade spiradenocarcinomas carry loss-of-function TP53 mutations, while cylindromas may have disruptive mutations in DNMT3A. Thus, we reveal the genomic landscape of adnexal tumors and therapeutic targets.

Histopathologic correlation of high-risk MelaFindTM lesions: a 3-year experience from a high-risk pigmented lesion clinic

BACKGROUND

A significant number of pigmented lesions are biopsied to rule out melanoma, but most will be benign. MelaFindTM is a highly sensitive, noninvasive computer-assisted system to aid in clinical diagnosis of melanoma.

METHODS

A total of 140 high-risk patients were followed by one expert dermatologist. Biopsies were blindly and independently evaluated by two dermatopathologists and given histologic severity scores (HSS, 0-12) based on the histologic features of melanoma/dysplastic nevi and compared to pathologic diagnoses and MelaFindTM scores.

RESULTS

MelaFindTM reduced the biopsy number of clinically ambiguous lesions (923 scanned to 253 biopsied, 73% reduction). Biopsied cases were usually benign (135/253, 53.4%, HSS = 2.8-3.2). Dysplastic nevi with varying degrees of atypia were observed next most commonly (80/253, 31.6%, HSS = 4.7-5.2 for mild dysplasia and 7-7.6 for moderate to severe dysplasia). Melanomas comprised 11/253 (4.3%) of biopsies (HSS = 9.3-10.7). Twenty-four cases were given miscellaneous diagnoses not within the dysplastic nevus-melanoma spectrum (9.5%, HSS = 1.3). Dermal fibrosis was the most commonly identified worrisome histologic feature (177/253, 70%), closely followed by other known atypical features. Nonthreatening histologic features in benign lesions with high MelaFindTM disorganization scores were common. The HSS differed significantly depending on pathologic diagnosis severity, while the MelaFindTM score did not (benign = 2.2; mildly atypical = 4.8; moderately to severely atypical = 2.3; in-situ or invasive melanoma = 3.1).

CONCLUSIONS

MelaFindTM unequivocally reduced the number of biopsies, but banal lesions had histologic attributes resulting in high-risk MelaFindTM scores, and MelaFindTM does not correlate with degree of cytologic atypia. Knowledge of these limitations should increase bidirectional confidence when making clinicopathologic correlations in high-risk patients.

Low-dose IL-12 preconditions the tumor microenvironment to enhance the efficacy of PD-1 blockade

20

Background: The immunomodulatory effects of IL-12 are well known to result in potent anti-tumor responses. However its therapeutic development has been hindered by its potential toxicity. Here we explored the impact of systemic low dose IL-12 administration as a strategy to enhance the efficacy of PD-1 blockade. Methods: Mice bearing D4M melanoma tumors were treated with anti PD-1 antibody alone or in combination with low dose IL-12 (100ng twice a week). Tumor progression was monitored, and characterization of immune cell types was performed by flow cytometry and gene expression analysis. Results: A significant reduction in tumor progression after combinatorial treatment with low dose IL-12 and anti PD-1 was observed. This synergistic effect was associated with elevated levels of intratumoral IFN-γ, iNOS, CXCL9, CXCL10, CXCL11, and perforin. Single treatment with low dose IL-12 induced a decrease in the levels of circulating neutrophils and an increase in the levels of circulating CD8+ T cells. Within the TME, low dose IL-12 treatment was associated with an increase in the frequencies of tumor infiltrating M-MDSCs expressing high levels of CXCL9. Elevated levels of CD8+ TILs were also found, which were characterized by their increased expression of PD-1 and PD-L1, as well as CD107a, CXCR3 and CD103. No signs of toxicity were noted. Conclusions: Low dose IL-12 synergizes with anti PD-1 to induce superior regression of D4M melanoma tumors. This effect was associated with an increase in the levels of molecules involved in the recruitment and effector function of CD8+ T cells. Analysis of tissues from animals treated with low dose IL-12 alone showed significant changes in the composition and phenotype of myeloid and T cells in both the tumor and blood. Expression of CXCL9 on tumor infiltrating MDSCs suggested a reversal of their immunosuppressive function to an immunopromoting one, and could explain the elevated accumulation of CD8+ TILs via enhanced CXCR3-dependent recruitment. These findings suggest that low dose IL-12 is sufficient to induce changes in the TME, with minimal toxicity,that enhance the anti-tumor effects of PD-1 blockade. A clinical study testing the safety of this combination is currently underway.

Immune-Checkpoint Blockade Opposes CD8+ T-cell Suppression in Human and Murine Cancer

Immune-checkpoint blockade enhances antitumor responses against cancers. One cancer type that is sensitive to checkpoint blockade is squamous cell carcinoma of the head and neck (SCCHN), which we use here to study limitations of this treatment modality. We observed that CD8⁺ tumor-infiltrating lymphocytes (TILs) in SCCHN and melanoma express excess immune checkpoints components PD-1 and Tim-3 and are also CD27^-/CD28^-, a phenotype we previously associated with immune dysfunction and suppression. In ex vivo experiments, patients' CD8⁺ TILs with this phenotype suppressed proliferation of autologous peripheral blood T cells. Similar phenotype and function of TILs was observed in the TC-1 mouse tumor model. Treatment of TC-1 tumors with anti-PD-1 or anti-Tim-3 slowed tumor growth in vivo and reversed the suppressive function of multi-checkpoint⁺ CD8⁺ TIL. Similarly, treatment of both human and mouse PD-1⁺ Tim-3⁺ CD8⁺ TILs with anticheckpoint antibodies ex vivo reversed their suppressive function. These suppressive CD8⁺ TILs from mice and humans expressed ligands for PD-1 and Tim-3 and exerted their suppressive function via IL10 and close contact. To model therapeutic strategies, we combined anti-PD-1 blockade with IL7 cytokine therapy or with transfer of antigen-specific T cells. Both strategies resulted in synergistic antitumor effects and reduced suppressor cell function. These findings enhance our understanding of checkpoint blockade in cancer treatment and identify strategies to promote synergistic activities in the context of other immunotherapies.

Weaning of Veno-venous Bypass in Liver Transplantation: A Single Center Experience

BACKGROUND

Veno-venous bypass (VVB) has been used in liver transplantation (LT) to minimize hemodynamic instability during caval anastomosis of anhepatic phase. With the introduction of the piggyback (PB) technique, which is a caval-sparing technique, the use of VVB progressively decreased over the world. The aim of this study was to introduce our experience using VVB with the focus on its weaning process.

METHODS

A total of 300 consecutive LT cases from May 1996 to November 2003 were examined. Except for pediatric LT, 242 LT cases were investigated to evaluate the trends in VVB use, surgical technique, the amount of transfusion requirements, and durations of operation and anhepatic phase.

RESULTS

For the early 100 LT cases, VVB was used in 97.5% of recipients, especially in all the recipients of deceased donor LT (DDLT). Then, the frequency of VVB use was decreased, and VVB was not used after the 268th recipient. In DDLT, the PB technique was first introduced in the 58th recipient and became a routine procedure of the DDLT since the 191th recipient. Living donor LT was increased, and the amount of transfusion requirement, duration of operation, and duration of anhepatic phase was reduced over time.

CONCLUSIONS

The increasing experience and sophisticated surgical and anesthetic techniques were important factors responsible for the weaning of VVB. The advancement of the PB technique used in living donor LT might be a main factor of its weaning.

Association of Platelet Count and Platelet Transfusion With Serotonin Level During Living Donor Liver Transplantation: Possible Connection to Graft Regeneration

BACKGROUND

We recently showed that platelet counts and the amount of platelet transfusion during liver transplantation are positively associated with early graft regeneration. It was hypothesized that platelet-derived serotonin mediates liver regeneration.

OBJECTIVES

This study aimed to evaluate the association between intraoperative platelet count, platelet transfusion, and serum serotonin level.

METHODS

Thirty-two recipients undergoing living-donor liver transplantation were enrolled into this prospective observational study. Serum platelet counts and serotonin levels were measured at the following times: anesthetic induction, start of the anhepatic phase, before graft reperfusion, 5 minutes/1 hour/3 hours/5 hours after graft reperfusion, and before/after platelet transfusion. Serotonin was measured by using a liquid chromatography tandem mass spectrometry.

RESULTS

Serotonin level at the anesthetic induction was 24.5 μg/mL (interquartile range, 14.6 to 38.1 μg/mL). During surgery, serial changes in platelet counts and serotonin levels showed a similar trend: they decreased during the anhepatic phase, increased during the first hour after graft reperfusion, and thereafter gradually decreased. Serotonin level was positively correlated with platelet counts (correlation coefficient = 0.620, P < .001). Allogeneic platelet transfusion significantly increased platelet count from 22 (19-31) × 10⁹/L to 53 (50-81) × 10⁹/L (P = .008) and it also increased serum serotonin from 11.04 (6.41-15.34) μg/mL to 34.26 (25.86-41.94) μg/mL (P = .008).

CONCLUSIONS

Our findings indicate that allogeneic platelets could act as effector cells deriving serotonins. Also, our findings support the hypothesis that the association between platelets and post-transplantation graft regeneration is mediated by serotonin. Further studies are warranted regarding the respective role of serotonin and other platelet-derived molecules mediating liver regeneration.

Ischemic Preconditioning Produces Comparable Protection Against Hepatic Ischemia/Reperfusion Injury Under Isoflurane and Sevoflurane Anesthesia in Rats

BACKGROUND

Various volatile anesthetics and ischemic preconditioning (IP) have been demonstrated to exert protective effect against ischemia/reperfusion (I/R) injury in liver. We aimed to determine whether application of IP under isoflurane and sevoflurane anesthesia would confer protection against hepatic I/R injury in rats.

METHODS

Thirty-eight rats weighing 270 to 300 grams were randomly divided into 2 groups: isoflurane (1.5%) and sevoflurane (2.5%) anesthesia groups. Each group was subdivided into sham (n = 3), non-IP (n = 8; 45 minutes of hepatic ischemia), and IP (n = 8, IP consisting of 10-minute ischemia plus 15-minute reperfusion before prolonged ischemia) groups. The degree of hepatic injury and expressions of B-cell lymphoma 2 (Bcl-2) and caspase 3 were compared at 2 hours after reperfusion.

RESULTS

Hepatic ischemia induced significant degree of I/R injuries in both isoflurane and sevoflurane non-IP groups. In both anesthetic groups, introduction of IP dramatically attenuated I/R injuries as marked by significantly lower aspartate aminotransferase and aminotransferase levels and better histologic grades compared with corresponding non-IP groups. There were 2.3- and 1.7-fold increases in Bcl-2 mRNA levels in isoflurane and sevoflurane IP groups, respectively, compared with corresponding non-IP groups (both P < .05). Caspase 3 level was significantly high in the isoflurane non-IP group compared with the sham group; however, there were no differences among the sevoflurane groups.

CONCLUSIONS

The degree of hepatic I/R injury was significantly high in both isoflurane and sevoflurane groups in rats. However, application of IP significantly protected against I/R injury in both volatile anesthetic groups to similar degrees, and upregulation of Bcl-2 might be an important mechanism.

The Immunology of Melanoma

The relatively high DNA mutational burden in melanoma allows for the creation of potentially "foreign," immune-stimulating neoantigens, and leads to its exceptional immunogenicity. Brisk tumor-infiltrating lymphocytes, a marker of immune editing, confer improved overall survival in melanoma, possibly due to reduced sentinel lymph node spread. Meanwhile, T-cell-stimulating drugs, so-called T-cell checkpoint inhibitors, which reverse peripheral tolerance-dependent tumor escape, have demonstrated unparalleled clinical success in metastatic melanoma. Markers to predict response to immunotherapy are currently imperfect, and the subject of intense research, which will guide the future of ancillary pathologic testing in this setting.

Effect of topical loteprednol etabonate with lid hygiene on tear cytokines and meibomian gland dysfunction in prosthetic eye wearers

PurposeTo assess tear cytokine levels and clinical outcomes in meibomian gland dysfunction (MGD) in the blind eye of patients wearing an ocular prosthesis after 2 months of treatment with topical loteprednol etabonate and eyelid scrubs with warm compresses.Patients and methodsThis study included patients with MGD wearing a unilateral ocular prosthesis for more than 1 year. All patients topically received 0.5% loteprednol etabonate and were instructed to scrub their eyelids with warm compresses on the prosthetic eye for 2 months. We evaluated tear cytokine levels using Multiplex Bead Immunoassays, performed biomicroscopic examination of the lid margins and meibomian gland, conducted meibography imaging, and assessed MGD-related ocular symptoms using a questionnaire for the prosthetic eye before and 2 months after treatment.ResultsThirty consecutive patients were included. There were significant reductions in the levels of interleukin (IL)-6, interferon-γ, monocyte chemotactic protein-1, IL-8, tumor necrosis factor-α, and IL-1β (P<0.001 for each cytokine). Moreover, there were improvements in ocular symptoms (P=0.001), lid margin abnormalities (P<0.001), meibomian gland expressibility (P<0.001) and meibography findings (P=0.037).ConclusionTopical loteprednol etabonate in conjunction with eyelid scrubs and warm compresses were effective in treating MGD in prosthetic eye wearers. Furthermore, tear cytokine measurements may serve as an additional approach for evaluating the efficacy of anti-inflammatory treatment for MGD in prosthetic eye wearers.