Incidence Of Perineural Invasion Research Articles

Inclusion of Perineural Invasion with AJCC-TNM Staging: Outcomes from a South Asian Cohort of Curatively Treated Gastric Cancer Patients.

The incidence of perineural invasion (PNI) in patients with gastric cancer (GC) is high, and patients with PNI positive disease have a poor prognosis compared to PNI-negative disease. The present study aims to study the incidence and evaluate the impact of PNI on the survival outcome of a cohort of South Asian GC patients. All consecutive patients undergoing curative gastrectomy were included in the study. The incidence of PNI and correlation with different clinico-pathological features and overall survival was performed. A total of 59.54% had PNI-positive disease and the median OS of PNI + ve patients was 29.3months, while it was not reached in PNI-ve patients. The PNI positivity was a significant prognostic factor for overall survival both on univariate and multivariate analysis. On TNM-PNI staging, those with TNM stage I/II patients with PNI + ve disease had similar OS to all stage III patients (p = 0.835) and were worse than that of PNI-ve patients (p < 0.05). The incidence of PNI in gastric cancer is high. The inclusion of PNI with AJCC-TNM staging may better stratify prognostic staging in curatively treated gastric cancer patients.

The Impact of Nerve Involvement on the Prognosis of Gastric Cancer Patients with Curative Gastrectomy: An International Multicenter Analysis.

Background Several studies have been conducted to investigate the association between the presence of perineural invasion (PNI) and overall survival (OS) of gastric cancer (GC) patients who underwent curative resection, but no consensus has been reached. This study is aimed at determining the prognostic significance of PNI in gastric cancer. Study Design. The data of 2969 patients with gastric cancer and who had undergone curative gastrectomy from 2006 to 2010 in two high-volume hospitals of China and Korea were retrospectively analyzed. PNI positivity was identified when carcinoma cells were found to infiltrate into the perineurium or neural fascicles. The relationships between PNI and other clinicopathological factors were evaluated, and survival analyses were performed. Results The presence of PNI was detected in 1055 of the 2969 patients (35.5%). Nationality, age, tumor location, size of tumor, differentiation of the tumor, pT stage, pN stage, lymphatic invasion, and vascular invasion had been associated with PNI positivity. The mean survival time of patients with and without PNI was 62.5 months and 87.3 months, respectively (P < 0.001). However, the presence of PNI was not an independent prognostic factor for gastric cancer, except for patients in stage III (P = 0.037, hazard ratio: 1.21, 95% confidence interval: 1.01-1.44). Conclusion PNI occurs frequently in patients with gastric cancer, and the incidence of PNI increases with the staging of the tumor. The presence of PNI can provide additional information in predicting the survival outcome for those with stage III tumors.

The association of lymph node involvement with lenfovascular invasion, perineural invasion and peritumoral lymphocytic reaction in surgically treated colon cancer patients

Aim: The American Joint Committee on Cancer (AJCC) tumor-node-metastasis (TNM) cancer staging system is the strongest prognostic parameter for colorectal cancer. However, additional markers are needed to improve clinical decision making. The aim of this study was to investigate the effects of lenfovascular invasion (LVI), perineural invasion (PNI) and peritumoral lymphocytic reaction (PLR) on lymph node involvement in surgically treated colon cancer patients.Materials and Methods: The historical records of patients having undergone colon cancer surgery in the Department of General Surgery were evaluated. In addition to demographic data and pathological TNM staging, parameters including tumor location, type, differentiation, LVI, PNI, PLR and tumor growth pattern were recorded and analyzed. p<0.05 was considered as statistically significant.Results: The study group of 71 patients consisted of 39 (54.9%) men and 32 (45.1%) women with a mean age of 65.1±12.3 (range: 39- 89) years. Tumors were located in the ascending colon in 18 (25.4%) patients, in the transverse colon in 3 (4.2%), in the descending colon in 8 (11.2%) and in the sigmoid colon in 42 (59.2%) patients. According to the postoperative histopathological examinations LVI was detected in 65 (91.6%) cases whereas PNI was found in 14 (19.7%) cases. PLR was detected in 69 (97.2%) cases that was mild in 53 (74.6%) and moderate in 16 (22.6%) cases. The incidence of PNI was significantly higher in stage N2 cases (p=0.001). On the other hand, no significant differences were found among N stage groups regarding LVI or PLR (p=0.409 and p=0.441, respectively). Although it was detected that LVI and PLR were present concomitantly in 63 (88.7%) cases, no significant differences were detected between mild, moderate or negative PLR with respect to LVI positivity (p=0.748).Conclusion: PNI was associated with increased lymph node involvement. Larger prospective randomized controlled studies are needed to be conducted in order to establish additional prognostic parameters in colon cancer surgery.

Patterns of incidental perineural invasion and prognosis in cutaneous squamous cell carcinoma: A multicenter, retrospective cohort study

Patterns of incidental perineural invasion and prognosis in cutaneous squamous cell carcinoma: A multicenter, retrospective cohort study

Neurosurgical management of perineural metastases: A case series and review of the literature.

Background: Perineural invasion (PNI) and spread are one of the grimmest prognostic factors associated with primary skin and head-and-neck cancers, yet remain an often confused, and underreported, phenomenon. Adding complexity to reaching a diagnosis and treating perineural spread (PNS) is the finding that patients may have no known primary tumor, history of skin cancer, and/or incidental PNI in the primary tumor. These delays in diagnosis and treatment are further compounded by an already slow disease process and often require multidisciplinary care with combinations of stereotactic radiosurgery, surgical resection, and novel treatments such as checkpoint inhibitors.Methods: Six patients with metastatic cancer to the cranial nerves who underwent Gamma Knife radiosurgery (GKRS) treatment were chosen for retrospective analysis. This information included age, gender, any past surgeries (both stereotactic and regular surgery), dose of radiation and volume of the tumor treated in the GKRS, date of PNS, comorbidities, the patient follow-up, and pre- and post-GKRS imaging. The goal of the follow-up with radiographing imaging was to assess the efficacy of GKSS.Results: The clinical course of six patients with PNS is presented. Patients followed variable courses with mixed outcomes: two patients remain living, one was lost to follow-up, and three expired with a median survival of 12 months from date of diagnosis. Patients at our institution are ideally followed for life.Conclusion: Given the morbidity and mortality of PNS of cancer, time is limited, and further understanding is required to improve outcomes. Here, we provide a case series of patients with PNS treated with stereotactic radiosurgery, discuss their clinical courses, and review the known literature.

The Length of Peri-Neural Spreading in Clinically Mandibular Invaded Oral Cavity Squamous Cell Carcinoma

Background: The objective of surgical management of oral squamous cell carcinoma (OSCC) is adequate resection with a clear margin. However, there is still a debate as to the optimal length for a mandibular resected margin. Objective: To examine the length of peri-neural spreading in T4 mandibular invaded oral cavity squamous cell carcinoma. Materials and Methods: Twenty-eight T4 pathological OSCC specimens that involved mandible and serial slices were studied and the length of tumor spreading along the inferior alveolar nerve (IAN) was determined. Tumor characteristics, risk factors, and survival were analyzed. Results: The incidence of peri-neural invasion was 11.11%, and IAN invasion was found in 14.29% of the tumor-invaded mandibular marrow. The length of tumor spreading along IAN was 3 to 12 mm. Poor prognostic factors of T4 OSCC were it being located on the tongue (HR 14.16), was pathological N2-3 (HR 31.05), and had high-risk features such as peri-neural invasion, lymphovascular invasion, and extra-nodal extension. Conclusion: A mandibular resected margin of at least 18 mm is recommended as a clear surgical margin in cases of T4 mandibular invasion OSCC. Keywords: Oral cancer, Perineural invasion, Inferior alveolar nerve, Squamous cell carcinoma, Mandibulectomy

The Length of Peri-Neural Spreading in Clinically Mandibular Invaded Oral Cavity Squamous Cell Carcinoma

Background: The objective of surgical management of oral squamous cell carcinoma (OSCC) is adequate resection with a clear margin. However, there is still a debate as to the optimal length for a mandibular resected margin. Objective: To examine the length of peri-neural spreading in T4 mandibular invaded oral cavity squamous cell carcinoma. Materials and Methods: Twenty-eight T4 pathological OSCC specimens that involved mandible and serial slices were studied and the length of tumor spreading along the inferior alveolar nerve (IAN) was determined. Tumor characteristics, risk factors, and survival were analyzed. Results: The incidence of peri-neural invasion was 11.11%, and IAN invasion was found in 14.29% of the tumor-invaded mandibular marrow. The length of tumor spreading along IAN was 3 to 12 mm. Poor prognostic factors of T4 OSCC were it being located on the tongue (HR 14.16), was pathological N2-3 (HR 31.05), and had high-risk features such as peri-neural invasion, lymphovascular invasion, and extra-nodal extension. Conclusion: A mandibular resected margin of at least 18 mm is recommended as a clear surgical margin in cases of T4 mandibular invasion OSCC. Keywords: Oral cancer, Perineural invasion, Inferior alveolar nerve, Squamous cell carcinoma, Mandibulectomy

The Length of Peri-Neural Spreading in Clinically Mandibular Invaded Oral Cavity Squamous Cell Carcinoma

Background: The objective of surgical management of oral squamous cell carcinoma (OSCC) is adequate resection with a clear margin. However, there is still a debate as to the optimal length for a mandibular resected margin. Objective: To examine the length of peri-neural spreading in T4 mandibular invaded oral cavity squamous cell carcinoma. Materials and Methods: Twenty-eight T4 pathological OSCC specimens that involved mandible and serial slices were studied and the length of tumor spreading along the inferior alveolar nerve (IAN) was determined. Tumor characteristics, risk factors, and survival were analyzed. Results: The incidence of peri-neural invasion was 11.11%, and IAN invasion was found in 14.29% of the tumor-invaded mandibular marrow. The length of tumor spreading along IAN was 3 to 12 mm. Poor prognostic factors of T4 OSCC were it being located on the tongue (HR 14.16), was pathological N2-3 (HR 31.05), and had high-risk features such as peri-neural invasion, lymphovascular invasion, and extra-nodal extension. Conclusion: A mandibular resected margin of at least 18 mm is recommended as a clear surgical margin in cases of T4 mandibular invasion OSCC. Keywords: Oral cancer, Perineural invasion, Inferior alveolar nerve, Squamous cell carcinoma, Mandibulectomy

Keratinocyte cancer with incidental perineural invasion: A registry analysis of management and 5-year outcomes.

Perineural invasion within keratinocyte cancer is a hallmark of tumour aggression, and a definitive treatment paradigm for this condition remains undetermined. Our aim was to investigate the treatment and outcomes of keratinocyte cancer with incidental perineural invasion within two skin cancer databases to refine treatment protocols. We retrospectively assessed the Queensland Perineural Invasion Registry for surgery, histopathology, adjuvant radiotherapy and recurrence of keratinocyte cancer five years post-definitive treatment. We also reviewed the Princess Alexandra Hospital Head and Neck clinical perineural invasion database, specifically looking at surgical margins and adjuvant radiotherapy of cutaneous squamous cell carcinoma (cSCC) with incidental perineural invasion in the primary lesion. There was no recurrence at 5years in the Perineural Invasion Registry. Basal cell carcinoma (BCC) lesions with nerves <0.1mm were more commonly treated with surgery alone, compared to lesions with nerves ≥0.1mm which were offered adjuvant radiotherapy. Of the total BCC lesions with incidental perineural invasion, those with perineural margins ≥5mm and peripheral tumour margins ≥3mm were predominantly treated with surgery alone. Eighty-nine per cent of cSCC lesions with incidental perineural invasion were treated with surgery and adjuvant radiotherapy. Surgery alone is suitable for BCC lesions with incidental perineural invasion. The majority of BCC lesions achieved ≥5mm perineural and ≥3mm peripheral tumour margins. Future research can guide if adjuvant radiation is required for BCC with perineural invasion. The treatment of cSCC with incidental perineural invasion with surgery alone remains undetermined.

Perineural invasion is associated with poor prognosis of colorectal cancer: a retrospective cohort study.

Perineural invasion (PNI) is associated with poor prognosis in a variety of cancers. Our aim was to determine the clinicopathological factors associated with PNI in colorectal cancer (CRC) and its impact on patient survival. The clinical data of 1412 patients diagnosed with CRC from July 2013 to July 2016 were retrospectively collected. PNI was determined based on hematoxylin-eosin staining. The relationships of PNI with various clinicopathological factors and prognosis were analyzed. The incidence of PNI in the entire cohort was 21.5%. PNI was significantly more common in patients with lower tumor differentiation, higher tumor stage, vascular invasion, TNM stage, tumor diameter, MMR/KRAS/NRAS/BRAF mutation, and more positive lymph nodes. Logistic regression analysis showed that T stage, vascular invasion, tumor diameter, and MMR were the main influencing factors of PNI. Cox regression analysis showed that poor tumor differentiation, N stage, TNM stage, PNI, and BRAF status were independent prognostic factors for OS. The OS, CSS, and PFS rate of the PNI (-) group was higher than that of the PNI (+) group, and the difference was statistically significant (P < 0.001). PNI in patients with colorectal cancer is significantly associated with T stage, TNM stage, vessel invasion, tumor diameter, MMR status, and BRAF mutation. PNI status is an independent prognostic factor for CRC. Assessing the postoperative PNI status may help predict prognosis and determine further treatment options for these patients.

Analysis of factors related to perineural invasion in cervical cancer and its relationship with prognosis

Objective To investigate the relationship between perineural invasion (PNI) and the clinicopathological features of cervical cancer, and to explore its influence on the prognosis of cervical cancer patients. Methods Retrospective analysis the clinical data of 76 patients with early cervical cancer who received radical hysterectomy+ pelvic lymphadenectomy±paraaortic lymphadenectomy from November 2015 to December 2019 in Xuanwu Hospital. The clinicopathological characteristics of the postoperative pathological results of cervical cancer patients were analyzed to explore the related factors of PNI and its influence on prognosis. Results Single factor analysis suggested that the incidence of PNI was related to tumor diameter, depth of stroma invasion, lymph-vascular space invasion, lymph node metastasis and clinical stage (P 0.05). Conclusions PNI is related to the depth of interstitial infiltration. PNI has no significant effect on the short-term recurrence rate and short-term survival rate of cervical cancer patients. Key words: Uterine cervical neoplasms; Perineural invasion; Prognosis; Factor analysis, statistical

Clinical diagnosis and treatment of perineural invasion of head and neck malignant tumors

Perineural invasion is a unique biological behavior of tumors via nerve dissemination and metastasis, which is intimately correlated with the recurrence, metastasis and prognosis. With the deepening research, the clinical significance of perineural invasion has been widely recognized. However, due to the low incidence of head and neck neoplasms and the varying incidence of perineural invasion in different anatomical sites and pathological types, high-level evidence-based medical evidence is still lacking. Currently, the pathological mechanism of perineural invasion has not been clearly clarified. No specific treatment has been available for perineural invasion. Therefore, the treatment of perineural invasion of head and neck tumors is an enormous challenge for clinicians. In this article, the current status of clinical diagnosis and treatment of perineural invasion in head and neck malignancies was reviewed. Key words: Head and neck neoplasm; Perineural invasion; Diagnosis and treatment

Long-term clinical outcomes of patients with invasive cutaneous squamous cell carcinoma treated with Mohs micrographic surgery: A 5-year, multicenter, prospective cohort study

Outcomes for patients with cutaneous squamous cell carcinoma (CSCC) treated with Mohs micrographic surgery (MS) in the United States have never been prospectively defined. Risk factors as they relate to outcomes are primarily derived from single-institution, retrospective data without regard for treatment modality. The American Joint Committee on Cancer Staging Manual, Eighth Edition, and the Brigham and Women's Hospital T staging systems have not been prospectively validated. To prospectively quantify outcomes by T stage and verify historically high-risk features as they pertain to outcomes in MS-treated CSCC. A 5-year, prospective, multicenter analysis of patients undergoing MS for invasive CSCC was conducted. The study enrolled 647 patients with 745 tumors. The 5-year local recurrence (LR)-free survival, nodal metastasis (NM)-free survival, and disease-specific survival were 99.3%, 99.2%, and 99.4%, respectively. Both staging systems were predictive of NM, disease-specific death, and all-cause death; neither was predictive of LR. Although Breslow depth was statistically associated with LR, NM, and disease-specific death, incidental perineural invasion was not. The Brigham and Women's Hospital and the American Joint Committee on Cancer Staging Manual, Eighth Edition T staging systems were published after study enrollment, therefore T stages were retrospectively applied using the prospectively collected data. MS is a highly effective treatment for CSCC and may mitigate factors typically considered high risk. Uniform reporting of Breslow depth should be considered in CSCC. The American Joint Committee on Cancer Staging Manual, Eighth Edition, and the Brigham and Women's Hospital staging system are useful prognosticators but are not predictive of LR after MS.

Long-term outcomes of patients with intraductal growth sub-type of intrahepatic cholangiocarcinoma

Background: Intrahepatic cholangiocarcinoma (ICC) is morphologically classified as mass forming (MF), periductal infiltrating (PI) or intraductal growth (IG) type. We sought to investigate the characteristics and long-term outcomes of IG patients compared with MF and PI ICC. Methods: 1,083 patients who underwent curative-intent liver resection for ICC between 1990-2015 were identified. Data on clinico-pathological characteristics, operative details, and morphological status were analyzed. Results: ICC morphology consisted of MF (n=911, 84%), PI (n=142, 13%), or IG (n=30, 3%) subtypes. Among patients with IG ICC, 63% has a T1a/T1b tumor and the majority of patients (67%) were node negative. Most patients with MF (52%) or PI (78%) had more advanced T2/T3/T4 disease; the incidence of lymph-node metastasis among MF (34%) or PI (59%) was comparable (p>0.05). On final pathology, the incidence of R0 margins was also similar among IG (93%) and MF (89%)(p=0.46), yet lower among patients with PI (77%)(p=0.04). Lympho-vascular invasion (IG, 13% vs. MF, 29% vs. PI, 46%) was lower among patients with IG (p< 0.001). In addition, the incidence of perineural invasion was also lower among IG patients (IG, 17% vs. MF, 18% vs. PI, 38%; p=0.03). While 5-year overall survival was comparable among patients with IG (41%) and MF (42%), long-term outcome was lower among patients with PI (25%)(p=0.04). Conclusion: Patients with IG tended to present with earlier T-stage disease, yet had the same overall incidence of nodal metastasis. Long-term outcomes were comparable to the most common MF subtype, yet was better than PI.

Perineural invasion: Independent prognostic factor in oral cancer that warrants adjuvant treatment.

Controversy exists regarding the administration of adjuvant radiotherapy (RT) when perineural invasion (PNI) is the only adverse histological feature. The purpose of this study was to evaluate the impact of PNI on the survival of patients with oral cavity squamous cell carcinoma (SCC). A retrospective study of 1524 treatment naive patients with oral cavity SCC who underwent surgery from January 2012 to March 2015 was conducted. Survival analysis was performed using Cox regression model. The incidence of PNI was 20.3% and higher in tongue cancers (odds ratio 2.43). The PNI significantly affected both disease-free survival (DFS; hazard ratio [HR] 1.84) as well as overall survival (OS; HR 1.7). Patients with early node-negative oral cavity SCC with PNI are more likely to develop recurrences and have mortality (HR 2.79 for DFS; HR 2.54 for OS). However, the addition of adjuvant radiation in these patients showed improvement in survival (p = .022). Forest plot analysis showed a trend toward poor survival across all subgroups in patients with PNI. Aggressive treatment of the primary cancer with the coincident management of the neck is important in the presence of PNI. The PNI worsens survival and warrants intensification of adjuvant treatment.

Infiltración perineural incidental en el carcinoma basocelular como factor de riesgo para recidiva local

BackgroundBasal cell carcinoma (BCC) is the most common non-melanoma skin cancer. There are risk factors for a more aggressive course, with one of them being incidental perineural invasion (IPN) (nerves with <0.1mm in diameter). However, there are no conclusive data about the clinical significance of this histological finding. MethodsA review was made of the cases of recurrent and non-recurrent BCC in the Salvador Zubirán National Institute of Medical Sciences and Nutrition (Instituto Nacional de Ciencias Médicas y Nutrición) from 2000-2013. An analysis was carried out on their clinical and histopathological characteristics. ResultsThere were 45 cases, 32 non-recurrent BCC, 12 recurrent BCC and 1 uncorroborated case. Sex distribution was 28 males and 17 women. The size of the tumours ranged from 3 to 25 mm, most of them in a high risk zone. The most common histological subtype was nodular. Incidental perineural invasion was found in 3 cases of non-recurrent BCC and in 1 case of recurrent BCC, p=0.806. ConclusionsThere is a lack of prospective studies that evaluate the clinical guidelines for BCC with incidental perineural invasion, as well as to define the true significance of this histological characteristic. In this study, IPN was not found to be negative risk factor.

Clinical and Incidental Perineural Invasion of Cutaneous Squamous Cell Carcinoma

ImportancePerineural invasion (PNI) in cutaneous squamous cell carcinoma (CSCC) has been associated with an increased risk of poor outcomes. Patients with PNI may present with clinical symptoms and/or radiologic evidence of PNI (clinical PNI [CPNI]), yet most patients are asymptomatic and PNI is often found on histologic examination (incidental PNI [IPNI]). Evidence-based estimates of the risks of disease-related outcomes comparing IPNI and CPNI are limited in the dermatology literature.ObjectivesTo review and synthesize outcomes data for patients with CSCC and CPNI or IPNI.Data SourcesA systematic review was conducted in MEDLINE and EMBASE for English-language articles published since inception to November 11, 2016.Study SelectionAll studies that reported a disease-related outcome (local recurrence, nodal metastasis, distant metastasis, or disease-specific death) of CSCCs with CPNI and IPNI were included.Data Extraction and SynthesisArticles were screened for eligibility, and any possible discrepancies in this screening were resolved. Data extracted included study characteristics, tumor characteristics, treatments performed, and disease-related outcomes. Overall risks of disease-related outcomes were generated by pooling patients from eligible studies. χ2 Statistics and Fisher exact tests were used to evaluate differences in disease-related outcomes.Main Outcomes and MeasuresRisks of disease-related outcomes and 5-year recurrence-free, disease-specific, and overall survival.ResultsA total of 12 studies containing 241 patients with CPNI and 381 patients with IPNI were included in the systematic review and analysis. The overall risks of local recurrence and disease-specific death were significantly higher in patients with CSCC and CPNI compared with those with CSCC and IPNI (local recurrence, 37% vs 17%; P < .001; disease-specific death, 27% vs 6%; P < .001). The risks of nodal metastasis and distant metastasis did not differ significantly by PNI classification. Patients with CSCC and CPNI had poorer mean 5-year recurrence-free survival and disease-specific survival compared with patients with IPNI (recurrence-free survival, 61% vs 76%; P = .009; disease-specific survival, 70% vs 88%; P = .002).Conclusions and RelevancePatients with CSCC and CPNI are at an increased risk of local recurrence and disease-specific death compared with patients with CSCC and IPNI and have a 30% risk of death. Patients with PNI may benefit from increased long-term surveillance. Further studies are needed to establish standardized guidelines on follow-up and dermatologic surveillance in this high-risk patient population.

Klatskin tumor: long-term survival following surgery

Perihilar cholangiocarcinoma (Klatskin tumor) is arare tumor entity with anunfavorable prognosis despite optimal treatment. The aim of the study is to investigate beneficial histopathological features and recommendations for surgery in perihilar cholangiocarcinoma to improve patients' long term survival. 192 patients suffering from perihilar cholangiocarcinoma underwent attempted tumor resection between 1998 and 2008 at our clinic. 50patients survived more than 2years. The follow-up ended in December 2013.The resection type, the UICC stage and histopathological features were compared between three groups (2-3-year, 3-5-year and >5-year survival groups). The overall 5‑year survival rate of the study groups was 32 %, and even 16 % survived more than 10years after surgery. Patients withlymph node positive tumors (p= 0.0126) and distant metastasis(p= 0.0376) had the poorest survival rate. Perineural invasion had no significant impact on the overall survival, but patients surviving more than 5years had the lowest incidence of perineural invasion with 18.75 %. Caudate lobectomy was significantly (p= 0.011) associated with a survival of more than 5years in our study. Complete tumor resection with additional caudate lobe resection is associated with long-term survival. Perineural invasion seems to be anegative prognostic factor for long-term survival.

Outcomes after surgery and postoperative radiotherapy for perineural spread of head and neck cutaneous squamous cell carcinoma.

Queensland, Australia, has the highest rates of cutaneous squamous cell carcinoma (SCC). Perineural invasion (PNI) is associated with reduced local control and survival. A retrospective review of a prospective database of patients with clinical PNI from cutaneous SCC of the head and neck (SCCHN) treated with surgery and postoperative radiotherapy (PORT) between 2000 and 2011 and a minimum of 24 months follow-up. Patients were excluded if immunosuppressed, had non-SCC histology, or were treated palliatively. Fifty patients (mean age, 60 years) with median follow-up of 50 months were included in this study. A total of 54.8% of known primary tumors had incidental PNI. Ten percent had nodal disease at presentation. MRI neurogram was positive in 95.8%. Recurrence-free survival (RFS) at 5-years was 62%. Five-year disease-specific survival (DSS) and overall survival (OS) were 75% and 64%, respectively. There were no perioperative deaths. This report demonstrates that long-term survival is achievable in patients with clinical PNI from cutaneous SCCHN after surgery and PORT. © 2015 Wiley Periodicals, Inc. Head Neck 38: 824-831, 2016.

Management of squamous cell and basal cell carcinomas of the head and neck with perineural invasion.

Perineural invasion (PNI) occurring in non-melanoma skin cancers (NMSC) is associated with an increased risk of locoregional recurrence and reduced disease-free survival. This necessitates early and accurate diagnosis, appropriate risk-stratification and a clear management strategy. The diagnosis of PNI is based on careful clinical assessment, imaging and histopathology. Surgery, preferably with margin control, and definitive or adjuvant radiotherapy (ART) are established treatment strategies for PNI. Clinical uncertainty remains over the role of ART in incidental PNI. This review synthesises current literature to ascertain which clinicopathological features impart a higher risk to individuals with PNI in NMSC, in order to provide treatment algorithms, including the identification of patient subsets that are most likely to benefit from ART. This includes those with extratumoural PNI, involvement of larger-calibre nerves, tumour invasion beyond dermis, recurrent tumour or diffuse intratumoural spread. Patients with clinical PNI may be optimally managed by a multidisciplinary head and neck cancer service that is best placed to offer skull base surgery and intensity-modulated radiation therapy (IMRT). The management options presented are stratified by histological subtype and a new classification of PNI into low-risk, medium-risk and high-risk groups.