Review of Perineural Invasion in Keratinocyte Carcinomas

A radiomics model for predicting perineural invasion in stage II-III colon cancer based on computer tomography

BACKGROUND

Colon cancer, a frequently encountered malignancy, exhibits a comparatively poor survival prognosis. Perineural invasion (PNI), highly correlated with tumor progression and metastasis, is a substantial effective predictor of stage II-III colon cancer. Nonetheless, the lack of effective and facile predictive methodologies for detecting PNI prior operation in colon cancer remains a persistent challenge.

METHOD

Pre-operative computer tomography (CT) images and clinical data of patients diagnosed with stage II-III colon cancer between January 2015 and December 2023 were obtained from two sub-districts of Sun Yat-sen Memorial Hospital (SYSUMH). The LASSO/RF/PCA filters were used to screen radiomics features and LR/SVM models were utilized to construct radiomics model. A comprehensive model, shown as nomogram finally, combining with radiomics score and significant clinical features were developed and validated by area under the curve (AUC) and decision curve analysis (DCA).

RESULT

The total cohort, comprising 426 individuals, was randomly divided into a development cohort and a validation cohort as a 7:3 ratio. Radiomics scores were extracted from LASSO-SVM models with AUC of 0.898/0.726 in the development and validation cohorts, respectively. Significant clinical features (CA199, CA125, T-stage, and N-stage) were used to establish combining model with radiomics scores. The combined model exhibited superior reliability compared to single radiomics model in AUC value (0.792 vs. 0.726, p = 0.003) in validation cohorts. The radiomics-clinical model demonstrated an AUC of 0.918/0.792, a sensitivity of 0.907/0.813 and a specificity of 0.804/0.716 in the development and validation cohorts, respectively.

CONCLUSION

The study developed and validated a predictive nomogram model combining radiomics scores and clinical features, and showed good performance in predicting PNI pre-operation in stage II-III colon cancer patients.

Lymphovascular Invasion in Cutaneous Squamous Cell Carcinoma

BACKGROUND

Although there is a large body of literature regarding risk stratification and outcomes for perineural invasion (PNI) in cutaneous squamous cell carcinoma (cSCC), there is a relative paucity of studies exploring the role of lymphovascular invasion (LVI) in cSCC and a lack of clear evidence-based guidelines for how to manage patients with these tumors.

OBJECTIVE

This article is intended to review the available literature regarding LVI in cSCC and formulate evidence-based recommendations for clinical management.

METHODS AND MATERIALS

A literature review was conducted using PubMed to find relevant articles relating to outcomes and management of primary cSCC with LVI.

RESULTS

The available literature suggests that LVI is a major risk factor for poor outcomes and increased morbidity and mortality in cSCC.

CONCLUSION

Lymphovascular invasion is a very high-risk feature that should place these tumors in the highest-risk category, and management of these tumors should be similar to that of squamous cell carcinoma with PNI.

Photodynamic Therapy in Treating a Subset of Basal Cell Carcinoma: Strengths, Shortcomings, Comparisons with Surgical Modalities, and Potential Role as Adjunctive Therapy

Basal cell carcinoma (BCC) is the most common skin cancer, for which there are multiple treatment options, including the gold standard Mohs micrographic surgery (MMS), surgical excision, electrodesiccation and curettage, radiation therapy, cryosurgery, and photodynamic therapy (PDT). While PDT is currently approved for treating actinic keratosis, it has been used off-label to treat BCC patients who may not tolerate surgery or other treatment modalities. We present a review of the efficacy of these modalities and describe important considerations that affect the usage of PDT and MMS. ALA-PDT and MAL-PDT are both efficacious treatment options for lower-risk BCC that can serve as non-invasive alternatives to surgical excision with favorable cosmetic outcomes in patients unsuitable to undergo surgery. In particular, PDT may be considered an adjuvant for the prevention and treatment of BCC lesions in patients with some genetic syndromes such as Gorlin syndrome, and in combination with surgical excision in lesions presenting in certain locations. Limitations to PDT include lack of margin control to prevent recurrence, pain, and cost of certain photosensitizers. Future studies should investigate the role of PDT as adjunctive therapy, standardization of protocols, and causes and ways to address recurrence following PDT treatment.

Predicting response to immunotherapy in gastric cancer via assessing perineural invasion-mediated inflammation in tumor microenvironment

BACKGROUND

The perineural invasion (PNI)-mediated inflammation of the tumor microenvironment (TME) varies among gastric cancer (GC) patients and exhibits a close relationship with prognosis and immunotherapy. Assessing the neuroinflammation of TME is important in predicting the response to immunotherapy in GC patients.

METHODS

Fifteen independent cohorts were enrolled in this study. An inflammatory score was developed and validated in GC. Based on PNI-related prognostic inflammatory signatures, patients were divided into Clusters A and B using unsupervised clustering. The characteristics of clusters and the potential regulatory mechanism of key genes were verified by RT-PCR, western-blot, immunohistochemistry and immunofluorescence in cell and tumor tissue samples.The neuroinflammation infiltration (NII) scoring system was developed based on principal component analysis (PCA) and visualized in a nomogram together with other clinical characteristics.

RESULTS

Inflammatory scores were higher in GC patients with PNI compared with those without PNI (P < 0.001). NII.clusterB patients with PNI had abundant immune cell infiltration in the TME but worse prognosis compared with patients in the NII.clusterA patients with PNI and non-PNI subgroups. Higher immune checkpoint expression was noted in NII.clusterB-PNI. VCAM1 is a specific signature of NII.clusterB-PNI, which regulates PD-L1 expression by affecting the phosphorylation of STAT3 in GC cells. Patients with PNI and high NII scores may benefit from immunotherapy. Patients with low nomogram scores had a better prognosis than those with high nomogram scores.

CONCLUSIONS

Inflammation mediated by PNI is one of the results of tumor-nerve crosstalk, but its impact on the tumor immune microenvironment is complex. Assessing the inflammation features of PNI is a potential method in predicting the response of immunotherapy effectively.

Basal Cell Carcinoma Perineural Invasion and Suggestive Signs of Perineural Invasion-Findings and Perspectives

Basal cell carcinoma (BCC) is a malignant tumor with a rising incidence and is the beneficiary of several innovative evaluation techniques. Histopathology remains the gold standard for assessment, having the possibility of addressing multiple high-risk factors such as perineural invasion (PNI). The current study included a number of 244 BCC patients and targeted the identification of positive PNI and its suggestive signs, and whether they correlated or not with other high-risk tumor signs. PNI was found in 20.1% of patients, with 30.7% of patients having perineural chronic inflammation (PCI), which is a suggestive sign of PNI. PNI was also found in larger tumors, with deeper Clark levels, in high-risk BCCs and high-grade tumors. PNI and PCI are both important for pathology reporting, aiding in treatment choice and further patient management, with possibly positive outcomes concerning morbidity and mortality.

Resection of Skin Cancer Resulting in Free Vascularized Tissue Reconstruction: Always a Therapeutic Failure?

The globally increasing incidence of cutaneous malignancies leads, in parallel, to increasing numbers of locally advanced skin cancer resulting in reconstructive surgery. Reasons for locally advanced skin cancer may be a patient's neglect or aggressive tumor growth, such as desmoplastic growth or perineural invasion. This study investigates characteristics of cutaneous malignancies requiring microsurgical reconstruction with the aim of identifying possible pitfalls and improving diagnostic and therapeutic processes. A retrospective data analysis from 2015 to 2020 was conducted. Seventeen patients (n = 17) were included. The mean age at reconstructive surgery was 68.5 (±13) years. The majority of patients (14/17, 82%) presented with recurrent skin cancer. The most common histological entity was squamous cell carcinoma (10/17, 59%). All neoplasms showed at least one of the following histopathological characteristics: desmoplastic growth (12/17, 71%), perineural invasion (6/17, 35%), or tumor thickness of at least 6 mm (9/17, 53%). The mean number of surgical resections until cancer-free resection margins (R0) were achieved was 2.4 (±0.7). The local recurrence rate and the rate of distant metastases were 36%. Identified high-risk neoplastic characteristics, such as desmoplastic growth, perineural invasion, and a tumor depth of at least 6 mm, require a more extensive surgical treatment without concerns about defect size.

Perineural Invasion in Vulvar Squamous-Cell Carcinoma Is an Independent Risk Factor for Cancer-Specific Survival, but Not for Locoregional Recurrence: Results from a Single Tertiary Referral Center

Simple Summary

Vulvar squamous cell carcinoma is a rare tumor but represents a serious health issue, especially due to the increasing incidence over the past decades. Many efforts have been made to identify new prognostic and therapeutic factors and, in this context, growing evidence concerning a pivotal role of perineural invasion. With this study, we investigated the role of perineural invasion in a large cohort of FIGO stage Ib-IIIc vulvar squamous cell carcinomas and found that perineural invasion-positive tumors have more aggressive biological behaviors and showed reduced cancer-specific survival as compared to perineural invasion-negative tumors, while this feature does not appear to be related to a greater risk to develop loco-regional recurrence. Further evaluations are warranted to confirm the prognostic role of perineural invasion and its potential use to tailor adjuvant treatment.

Abstract

The aims of this study were to assess the prevalence of perineural invasion (PNI) in vulvar squamous cell carcinoma (VSCC) and its prognostic role in locoregional recurrence (LRR) and cancer-specific survival (CSS). We performed a retrospective analysis of 223 consecutive stage IB–IIIC surgically treated VSCCs at S. Anna Hospital, University of Turin, from 2000 to 2019. We identified 133/223 (59.6%) patients with PNI-positive VSCCs. PNI was associated with aggressive biological features (i.e., advanced FIGO stage, larger tumor diameter, greater depth of invasion, a higher number of metastatic lymph nodes, and lymphovascular invasion) and shorter 5-year CSS (78% vs. 90%, log-rank p = 0.02) compared with PNI-negative VSCCs. Multivariate analysis showed that PNI (HR 2.99 CI 95% 1.17–7.63; p = 0.02) and the presence of tumor cells on pathological surgical margins (HR 3.13 CI 95% 1.37–7.13; p = 0.007) are independent prognostic factors for CSS. PNI does not appear to be related to LRR, but is an independent prognostic factor for worse survival outcomes. Future studies are necessary to explore the possible value of PNI in tailoring the choice of adjuvant treatment.