Prognostic significance of immune checkpoints in the tumour-stromal microenvironment of sebaceous gland carcinoma

The M2 macrophages infiltration of sebaceous tumors is linked to the aggressiveness of tumors but not to the mismatch repair pathway

PURPOSE

The immune microenvironment of sebaceous neoplasms (SNs) has been poorly explored, especially in benign lesions, and never correlated to the mismatch repair (MMR) status.

METHODS

We conducted an immuno-histological study to analyze the immune microenvironment of SNs. A tissue microarray was constructed including sebaceous adenomas (SAs), sebaceomas (Ss) and sebaceous carcinomas (SCs) to performed immuno-histological analysis of T cells, B cells, macrophages, dendritic cells, and expression of Programmed Death-1 (PD-1) and Programmed Death Ligand 1 (PD-L1). An automatized count was performed using the QuPath® software. Composition of the cellular microenvironment was compared to the aggressiveness, the MMR status, and to Muir-Torre syndrome (MTS).

RESULTS

We included 123 SNs (43 SAs, 19 Ss and 61 SCs) for which 71.5% had a dMMR phenotype. A higher infiltration of macrophages (CD68 +) of M2 phenotype (CD163 +) and dendritic cells (CD11c +) was noticed in SCs compared to benign SNs (SAs and Ss). Programmed cell death ligand-1 but not PD-1 was expressed by more immune cells in SCs compared to benign SNs. No difference in the immune cell composition regarding the MMR status, or to MTS was observed.

CONCLUSION

In SNs, M2 macrophages and dendritic cells infiltrates are associated with the progression and the malignant transformation of tumors. High PD-L1 expression in immune cells in SCs is an argument for the use of immunotherapy by anti-PD1 or PD-L1 in metastatic patients. The lack of correlation between the composition of immune cells in SNs and the MMR status emphasizes the singularity of SNs among MMR-associated malignancies.

Prognostic risk factors and nomogram construction for sebaceous carcinoma: A population-based analysis

Background

Sebaceous gland carcinoma (SGC) is a rare tumor for which there are currently no effective tools to predict patient outcomes. We analyzed the clinical and pathological prognostic risk factors of sebaceous carcinoma based on population data and created a nomogram of related risk factors, which can more accurately predict the 3-, 5-, and 10-year overall survival (OS) rates of patients.

Methods

SGC patients between 2004 and 2015 were collected from the Surveillance, Epidemiology, and End Results (SEER) database and randomly assigned to training and validation cohorts. Relevant risk factors were identified by univariate and multivariate COX hazards regression methods and combined to produce a correlation nomogram. The concordance index (C-index), the area under the receiver operating characteristic (AUC) curve, and calibration plots have demonstrated the predictive power of the nomogram. Decision curve analysis (DCA) was used to measure nomograms in clinical practice.

Results

A total of 2844 eligible patients were randomly assigned to 70% of the training group (n=1990) and 30% of the validation group (n=854) in this study. The derived meaningful prognostic factors were applied to the establishment of the nomogram. The C-index for OS was 0.725 (95% CI: 0.706-0.741) in the training cohort and 0.710 (95% CI: 0.683-0.737) in the validation cohort. The AUC and calibration plots of 3-, 5-, and 10-year OS rates showed that the nomogram had good predictive power. DCA demonstrated that the nomogram constructed in this study could provide a clinical net benefit.

Conclusion

We created a novel nomogram of prognostic factors for SGC, which more accurately and comprehensively predicted 3-, 5-, and 10-year OS in SGC patients. This can help clinicians identify high-risk patients as early as possible, carry out personalized treatment, follow-up, and monitoring, and improve the survival rate of SGC patients.

Neoadjuvant Systemic Chemotherapy in Sebaceous Gland Carcinoma of the Eyelid: A Retrospective Study

There are sparse data on neoadjuvant systemic chemotherapy (NACT) in eyelid sebaceous gland carcinoma (SGC). The aim of this study was to evaluate efficacy and outcomes with NACT in eyelid SGC. We retrospectively analyzed 8 patients who received platinum-based NACT. The median number of cycles per patient was 4 (range, 3-5). The mean percentage reduction of tumor diameter after NACT was 71% (range, 30-100%). Two patients had a radiological complete response (CR). After NACT, surgical treatment for residual tumor was performed in 5 cases. One patient had a pathological CR and is recurrence free for 11 years. After a mean follow-up period of 44.5 months (range, 9-109), tumor recurrence occurred in 4 cases. Among these 4 cases, 3 were rechallenged with the same regimen and all responded. Systemic NACT has a role in eyelid SGC, downstages the tumor, and allows less aggressive and organ-sparing surgeries, warranting a prospective study.

Prognostic impact of HERC2 protein and pink-eyed dilution protein in uveal melanoma

Biological understanding of pigmentation and its association with clinicopathological implications in uveal melanoma (UM) risk is still unexplored. HECT and RLD Domain Containing E3 Ubiquitin Protein Ligase 2 (HERC2) and Pink-eyed dilution protein (P-protein) are the important markers that regulate pigmentation in eye. Therefore, our aim of the study was to investigate the expression of HERC2 and P-protein in the UM patients and correlate with patient outcome. Fifty-two formalin-fixed paraffin-embedded UM tissue samples were included to detect the expression of HERC2 and P-protein by immunohistochemistry and validated by western blot. Cox proportional hazard model and log-rank test were used to determine the prognostic potential of these proteins. High pigmentation was seen in 67% of the UM cases. The expression of HERC2 and P-protein was present in 44% and 71% cases, respectively. On statistical analysis, increased pigmentation, epithelioid cell type, and ciliary body invasion were significant with the protein expressions (p < 0.05). Metastasis-free survival was reduced in UM cases which expressed HERC2 and P-protein. On multivariate analysis, P-protein expression was found to be an independent prognostic factor. Our findings suggest that HERC2 and P-protein could be used as novel predictors of high pigmentation in UM cases which have high metastatic potential.