Perineural invasion is associated with increased relapse after external beam radiotherapy for men with low-risk prostate cancer and may be a marker for occult, high-grade cancer

Prediction of liver metastasis and recommended optimal follow-up nursing in rectal cancer

We aimed to analyze and investigate the clinical factors that influence the occurrence of liver metastasis in locally advanced rectal cancer patients, with an attempt to assist patients in devising the optimal imaging-based follow-up nursing. Between June 2011 and May 2021, patients with rectal cancer at our hospital were retrospectively analyzed. A random survival forest model was developed to predict the probability of liver metastasis and provide a practical risk-based approach to surveillance. The results indicated that age, perineural invasion, and tumor deposit were significant factors associated with the liver metastasis and survival. The liver metastasis risk of the low-risk group was higher at 6-21 months, with a peak occurrence time in the 15th month. The liver metastasis risk of the high-risk group was higher at 0-24 months, with a peak occurrence time in the 8th month. In general, our clinical model could predict liver metastasis in rectal cancer patients. It provides a visualization tool that can aid physicians and nurses in making clinical decisions, by detecting the probability of liver metastasis.

Prognostic value of lymphovascular and perineural invasion in colorectal cancer

Background/Aim: Lymphovascular and perineural invasion (LVI and PNI, respectively) are associated with poor prognosis in various cancers. We sought to identify clinical variables associated with LVI and PNI in colorectal cancer (CRC) and their effects on survival. Methods: Our study design is consistent with a retrospective cohort study. Data from 237 patients with documented LVI or PNI who underwent surgery for colorectal cancer between 2017 and 2021 were retrospectively reviewed. Demographic characteristics, surgery and pathology reports, disease-free and overall survival (DFS and OS, respectively) of the patients were examined. Results: When the DFS duration of the patients were evaluated, The mean DFS of the LVI-negative group was 27.4 (15.09) months, and the mean of the LVI-positive patients was 20.45 (13) months. DFS was longer in the LVI-negative group (P<0.001). DFS was 52.26 (1.89) months in PNI-negative patients and 34.29 (2.71) months in PNI-positive patients. DFS expectation of PNI-positive patients was approximately 18 months less than that of negative patients (P<0.001). When the patients were evaluated in terms of OS duration, no significant difference was observed in LVI-negative and -positive patient groups, while the estimated OS duration was 52.29 (1.84) months in PNI-negative patients, and 40.10 (2.49) months in PNI-positive patients. OS was 12 months shorter in PNI-negative patients (P<0.001). Conclusion: The use of PNI and LVI together was found to have a significant impact on the survival rates of patients with colorectal cancer. Documenting LVI and PNI status in biopsy specimens can aid in the management, prognosis, and decision-making for treating colorectal tumors.

Perineural Invasion Predicts Local Recurrence and Poor Survival in Laryngeal Cancer

(1) Background: Perineural invasion (PNI) in head and neck cancer is associated with a poor prognosis; however, the effect of PNI on the prognosis of laryngeal cancer remains under debate. This retrospective study aimed to investigate the effect of PNI in fresh or salvaged larynges on survival in patients who had undergone laryngectomy for squamous cell carcinoma. (2) Methods: This study enrolled 240 patients diagnosed with laryngeal cancer who had undergone open surgery at Seoul St. Mary's Hospital, Korea. The effects of PNI, other histopathologic factors, and treatment history on survival and recurrence patterns were assessed. (3) Results: PNI was observed in 30 of 240 patients (12.5%). PNI (HR: 3.05; 95% CI: 1.90-4.88; p = 0.01) was a significant predictor of poor 5-year disease-free survival. In fresh cases, preepiglottic invasion (HR: 2.37; 95% CI: 1.45-3.88; p = 0.01) and PNI (HR: 2.96; 95% CI: 1.62-2.96; p = 0.01) were negative prognostic factors for 5-year disease-free survival. In the salvage group, however, only PNI (HR: 2.74; 95% CI: 1.26-5.92; p = 0.01) was a significant predictor of disease-free survival. Further, PNI significantly influenced high local recurrence (HR: 5.02, 95% CI: 1.28-9.66; p = 0.02). (4) Conclusions: Independent of treatment history, PNI is a prognostic factor for poor survival and local recurrence in laryngeal cancer.

A Recurrence Predictive Model for Node-negative Esophageal Squamous Cell Carcinoma After Upfront Esophagectomy

The prognosis for pathologically node-negative (pN0) esophageal squamous cell carcinoma (ESCC) with surgery alone remains poor. We aimed to develop a model for a more precise prediction of recurrence, which will allow personalized management for pN0 ESCC after upfront complete resection. Clinical and pathological records of patients with completely resected pT1-3N0M0 ESCC were retrospectively analyzed between January 2014 and December 2019. A nomogram for the prediction of recurrence was established based on the Cox regression analysis and evaluated by C-index, AUC, and calibration curves. The model was further validated using bootstrap resampling and k-fold cross-validation and compared with the 8th edition of the AJCC TNM staging system using Td-ROC, NRI, IDI, and DCA. Two-hundred-and seventy cases were included in this study. The median follow-up was 45 months. Distant and/or loco-regional recurrences were noted in 89 (33.0%) patients. The predictive model revealed pT-category, differentiation, perineural invasion, examined lymph nodes (ELN), and prognostic nutritional index (PNI) as independent risk factors for recurrence, with a c-index of 0.725 in the bootstrapping cohort. Td-ROC, NRI, and IDI showed a better predictive ability than the AJCC 8th TNM staging system. Based on this model, patients in the low-risk group had a significantly lower recurrence incidence than those in the high-risk group (p < .001). The predictive model developed in this study may facilitate the precise prediction of recurrences for pN0 ESCC after upfront surgery. Stratifying management of those patients might bring significantly better survival benefits.

Lumbosacral plexopathy caused by the perineural spread of pelvic malignancies: clinical aspects and imaging patterns

BACKGROUND

Perineural spread (PNS) of tumors from pelvic malignancies is a rare phenomenon but constitutes an important differential diagnosis of lumbosacral plexopathy (LSP). Herein, we describe the clinical and imaging features of patients with LSP due to PNS of pelvic malignancies along with a literature review.

METHODS

We retrospectively reviewed 9 cases of LSP caused by PNS of pelvic malignancy between January 2006 and August 2021, and all clinical and imaging parameters were recorded in detail. Clinical symptoms and signs of patients were described and listed in the order in which they occurred. The results of imaging test were analyzed to describe specific findings in LSP caused by PNS.

RESULTS

This study enrolled nine adult patients (mean age, 50.1 years). Two cases initially presented as LSP and were later diagnosed with pelvic malignancy. Pain in the perianal or inguinal area preceded pain at the extremities in six patients. Neurogenic bladder or bowel symptoms developed in five patients. On the magnetic resonance imaging (MRI), the S1-S2 spinal nerve was most commonly involved, and S1 myotome weakness was more prominent in six patients than the other myotomes. One patient had an intradural extension. ¹⁸F-Fluorodeoxyglucose (FDG) positron emission tomography (PET) and computed tomography (CT) showed abnormal signal intensity in six patients. No abnormality in ¹⁸F-FDG PET/CT was detected in the nervous structures in one patient. Only four patients survived until the last follow-up visit.

CONCLUSIONS

Though rare, physicians should always keep in mind the possibility of LSP due to the PNS in patients with pelvic malignancy. Thorough physical examination and history taking could provide clues for diagnosis. Pelvic MRI and ¹⁸F-FDG-PET/CT should be considered for patients with LSP to rule out neoplastic LSP.

Perineural invasion as a risk factor for locoregional recurrence of invasive breast cancer

Perineural invasion (PNI) is a pathologic finding observed across a spectrum of solid tumors, typically with adverse prognostic implications. Little is known about how the presence of PNI influences locoregional recurrence (LRR) among breast cancers. We evaluated the association between PNI and LRR among an unselected, broadly representative cohort of breast cancer patients, and among a propensity-score matched cohort. We ascertained breast cancer patients seen at our institution from 2008 to 2019 for whom PNI status and salient clinicopathologic features were available. Fine-Gray regression models were constructed to evaluate the association between PNI and LRR, accounting for age, tumor size, nodal involvement, estrogen receptor (ER), progesterone receptor (PR), HER2 status, histologic tumor grade, presence of lymphovascular invasion (LVI), and receipt of chemotherapy and/or radiation. Analyses were then refined by comparing PNI-positive patients to a PNI-negative cohort defined by propensity score matching. Among 8864 invasive breast cancers, 1384 (15.6%) were noted to harbor PNI. At a median follow-up of 6.3 years, 428 locoregional recurrence events were observed yielding a 7-year LRR of 7.1% (95% CI 5.5-9.1) for those with PNI and 4.7% (95% CI 4.2-5.3; p = 0.01) for those without. On univariate analysis throughout the entire cohort, presence of PNI was significantly associated with an increased risk of LRR (HR 1.39, 95% CI 1.08-1.78, p < 0.01). Accounting for differences in salient clinicopathologic and treatment parameters by multivariable Fine-Gray regression modeling, the association between PNI and LRR was potentiated (HR 1.57, 95% CI 1.2-2.07, p = 0.001). We further conducted propensity score matching to balance clinicopathologic parameters and treatments between the two groups (PNI vs not), again showing a similar significant association between PNI and LRR (HR 1.46, 95% CI 1.03-2.08, p = 0.034). PNI is significantly associated with LRR following the definitive treatment of invasive breast cancer. The excess risk conferred by PNI is similar in magnitude to that observed with LVI, or by ER/PR negativity. Breast cancer prognostication and therapeutic decision-making should consider the presence of PNI among other salient risk factors. Larger studies among more uniform breast cancer presentations may elucidate the extent to which these findings apply across breast cancer subtypes and stages.

Cancer-Associated Neurogenesis and Nerve-Cancer Cross-talk

In this review, we highlight recent discoveries regarding mechanisms contributing to nerve-cancer cross-talk and the effects of nerve-cancer cross-talk on tumor progression and dissemination. High intratumoral nerve density correlates with poor prognosis and high recurrence across multiple solid tumor types. Recent research has shown that cancer cells express neurotrophic markers such as nerve growth factor, brain-derived neurotrophic factor, and glial cell-derived neurotrophic factor and release axon-guidance molecules such as ephrin B1 to promote axonogenesis. Tumor cells recruit new neural progenitors to the tumor milieu and facilitate their maturation into adrenergic infiltrating nerves. Tumors also rewire established nerves to adrenergic phenotypes via exosome-induced neural reprogramming by p53-deficient tumors. In turn, infiltrating sympathetic nerves facilitate cancer progression. Intratumoral adrenergic nerves release noradrenaline to stimulate angiogenesis via VEGF signaling and enhance the rate of tumor growth. Intratumoral parasympathetic nerves may have a dichotomous role in cancer progression and may induce Wnt-β-catenin signals that expand cancer stem cells. Importantly, infiltrating nerves not only influence the tumor cells themselves but also impact other cells of the tumor stroma. This leads to enhanced sympathetic signaling and glucocorticoid production, which influences neutrophil and macrophage differentiation, lymphocyte phenotype, and potentially lymphocyte function. Although much remains unexplored within this field, fundamental discoveries underscore the importance of nerve-cancer cross-talk to tumor progression and may provide the foundation for developing effective targets for the inhibition of tumor-induced neurogenesis and tumor progression.

Heterozygous APC germline mutations impart predisposition to colorectal cancer

Familial adenomatous polyposis (FAP) is an inherited syndrome caused by a heterozygous adenomatous polyposis coli (APC) germline mutation, associated with a profound lifetime risk for colorectal cancer. While it is well accepted that tumorigenic transformation is initiated following acquisition of a second mutation and loss of function of the APC gene, the role of heterozygous APC mutation in this process is yet to be discovered. This work aimed to explore whether a heterozygous APC mutation induces molecular defects underlying tumorigenic transformation and how different APC germline mutations predict disease severity. Three FAP-human embryonic stem cell lines (FAP1/2/3-hESC lines) carrying germline mutations at different locations of the APC gene, and two control hESC lines free of the APC mutation, were differentiated into colon organoids and analyzed by immunohistochemistry and RNA sequencing. In addition, data regarding the genotype and clinical phenotype of the embryo donor parents were collected from medical records. FAP-hESCs carrying a complete loss-of-function of a single APC allele (FAP3) generated complex and molecularly mature colon organoids, which were similar to controls. In contrast, FAP-hESCs carrying APC truncation mutations (FAP1 and FAP2) generated only few cyst-like structures and cell aggregates of various shape, occasionally with luminal parts, which aligned with their failure to upregulate critical differentiation genes early in the process, as shown by RNA sequencing. Abnormal disease phenotype was shown also in non-pathological colon of FAP patients by the randomly distribution of proliferating cells throughout the crypts, compared to their focused localization in the lower part of the crypt in healthy/non-FAP patients. Genotype/phenotype analysis revealed correlations between the colon organoid maturation potential and FAP severity in the carrier parents. In conclusion, this study suggest that a single truncated APC allele is sufficient to initiate early molecular tumorigenic activity. In addition, the results hint that patient-specific hESC-derived colon organoids can probably predict disease severity among FAP patients.

A systematic review of nerve-sparing surgery for high-risk prostate cancer

INTRODUCTION

We provide a systematic analysis of nerve-sparing surgery (NSS) to assess and summarize the risks and benefits of NSS in high-risk prostate cancer (PCa).

EVIDENCE ACQUISITION

We have undertaken a systematic search of original articles using 3 databases: Medline/PubMed, Scopus, and Web of Science. Original articles in English containing outcomes of nerve-sparing radical prostatectomy (RP) for high-risk PCa were included. The primary outcomes were oncological results: the rate of positive surgical margins and biochemical relapse. The secondary outcomes were functional results: erectile function (EF) and urinary continence.

EVIDENCE SYNTHESIS

The rate of positive surgical margins differed considerably, from zero to 47%. The majority of authors found no correlation between NSS and a positive surgical margin rate. The rate of biochemical relapse ranged from 9.3% to 61%. Most of the articles lacked data on odds ratio (OR) for positive margin and biochemical relapse. The presented results showed no effect of nerve sparing (NS) on positive margin (OR=0.81, 0.6-1.09) or biochemical relapse (hazard ratio [HR]=0.93, 0.52-1.64). A strong association between NSS and potency rate was observed. Without NSS, between 0% and 42% of patients were potent, with unilateral 79-80%, with bilateral - up to 90-100%. Urinary continence was not strongly associated with NSS and was relatively good in both patients with and without NSS.

CONCLUSIONS

NSS may provide benefits for patients with urinary continence and significantly improves EF in high-risk patients. Moreover, it is not associated with an increased risk of relapse in short- and middle-term follow-up. However, the advantages of using such a surgical technique are unclear.

Laparoscopic pelvic exenteration and laterally extended endopelvic resection for postradiation recurrent cervical carcinoma: Technical feasibility and short-term oncologic outcome

OBJECTIVE

Surgery is the only treatment for cervical cancer recurrence in a previously irradiated field. Pelvic exenteration (PE) and laterally extended endopelvic resection (LEER) are indicated for select patients; however, morbidity and mortality rates remain high, and new treatment modalities are required. Laparoscopy optimizes visualization and allows meticulous dissection while also reducing intraoperative blood loss and postoperative complications without worsening the outcomes. We aimed to clarify the feasibility and outcomes of laparoscopic PE and LEER for previously irradiated recurrent cervical cancer.

METHODS

We prospectively investigated the outcomes of laparoscopic PE and LEER in 28 patients with recurrent cervical carcinoma after radiotherapy.

RESULTS

Seventeen laparoscopic PEs for central recurrences and 11 laparoscopic LEERs for lateral recurrences were performed. The median operation time and blood loss were 454mins and 285 mL in the PE group, and 562mins and 325 mL in the LEER group, respectively, with no conversions to laparotomy. R0 resection was achieved in all patients in the PE group and 73% in the LEER group. The morbidity and mortality rates were 41% and 0% in PE group, and 55% and 0% in LEER group, respectively. The 2-year disease-free survival and overall survival were 68.9% and 76% in the PE group, and 27.3% and 29.6% in the LEER group, respectively.

CONCLUSION

Laparoscopic PE is feasible for previously irradiated central recurrent cervical cancer and has acceptable outcomes. Laparoscopic LEER is also feasible for lateral recurrence, but oncologic outcome may be modest in this limited preliminary study. Further studies using a larger sample size with a longer follow-up period is warranted to determine the indications for laparoscopic LEER.

Perineural Invasion and Postoperative Complications are Independent Predictors of Early Recurrence and Survival Following Curative Resection of Gastric Cancer

Purpose

To investigate the clinicopathological and prognostic factors related to early gastric cancer recurrence after curative resection.

Patients and Methods

Between October 2006 and August 2018, a total of 149 patients with recurrence of gastric cancer/adenocarcinoma of the esophagogastric junction after curative resection were enrolled from our treatment group. A retrospective clinical analysis was performed on these patients with gastric cancer recurrence after curative resection.

Results

Among the 149 patients, 99 (66.4%) had only one recurrence pattern, and 50 (33.6%) had multiple recurrence patterns. The median recurrence-free survival (RFS) was 18.2 months (95% CI 15.0–21.4). Ninety-four patients (63.1%) experienced early recurrence (recurrence within 24 months after curative resection), and 55 patients (36.9%) experienced late recurrence (recurrence beyond 24 months after curative resection). The univariate analysis showed that perineural invasion (P=0.002), depth of invasion (P=0.026), postoperative chemotherapy (P=0.036) and postoperative complications (P=0.004) were significant factors associated with early recurrence after curative resection for gastric cancer. Perineural invasion (P=0.003), postoperative chemotherapy (P=0.036) and postoperative complications (P=0.042) were independent factors associated with early recurrence after curative resection in the multivariate analysis. The survival analysis showed that perineural invasion (P=0.011) and postoperative complications (P=0.007) were independent prognostic factors. The median survival time of early recurrence patients was significantly shorter than that of late recurrence patients (25.4 vs 62.9 months, P<0.001).

Conclusion

Perineural invasion, postoperative chemotherapy and postoperative complications were independent factors associated with early recurrence after curative resection. Patients with early recurrence after curative resection had poorer survival.

Nerves in cancer

The contribution of nerves to the pathogenesis of malignancies has emerged as an important component of the tumour microenvironment. Recent studies have shown that peripheral nerves (sympathetic, parasympathetic and sensory) interact with tumour and stromal cells to promote the initiation and progression of a variety of solid and haematological malignancies. Furthermore, new evidence suggests that cancers may reactivate nerve-dependent developmental and regenerative processes to promote their growth and survival. Here we review emerging concepts and discuss the therapeutic implications of manipulating nerves and neural signalling for the prevention and treatment of cancer.

Cdc42 Mediates Cancer Cell Chemotaxis in Perineural Invasion

Perineural invasion (PNI) is an ominous form of cancer progression along nerves associated with poor clinical outcome. Glial derived neurotrophic factor (GDNF) interacts with cancer cell RET receptors to enable PNI, but downstream events remain undefined. We demonstrate that GDNF leads to early activation of the GTPase Cdc42 in pancreatic cancer cells, but only delayed activation of RhoA and does not affect Rac1. Depletion of Cdc42 impairs pancreatic cancer cell chemotaxis toward GDNF and nerves. An siRNA library of guanine nucleotide exchange factors was screened to identify activators of Cdc42. ARHGEF7 (β-Pix) was required for Cdc42 activation and chemotaxis toward nerves, and also colocalizes with RET under GDNF stimulation. Cdc42 enables PNI in an in vitro dorsal root ganglia coculture model, and controls the directionality of migration but does not affect cell speed or cell viability. In contrast, Rac1 was necessary for cell speed but not directionality, while the RhoA was not necessary for either cell speed or directionality. Cdc42 was required for PNI in an in vivo murine sciatic nerve model. Depletion of Cdc42 significantly diminished the length of PNI, volume of PNI, and motor nerve paralysis resulting from PNI. Activated Cdc42 is expressed in human salivary ductal cancer cells invading nerves. These findings establish the GDNF-RET-β-Pix-Cdc42 pathway as a directional regulator of pancreatic cancer cell migration toward nerves, highlight the importance of directional migration in PNI, and offer novel targets for therapy. IMPLICATIONS: Cdc42 regulates cancer cell directional migration toward and along nerves in PNI.

Weighted Gene Co-Expression Network Analysis Identified Cancer Cell Proliferation as a Common Phenomenon During Perineural Invasion

Purpose

Perineural invasion (PNI) is the neoplastic invasion of nerves by cancer cells, a process that may prove to be another metastatic route besides direct invasion, lymphatic spread, and vascular dissemination. Given the increasing incidence and association with poor prognosis, revealing the pathogenesis of perineural invasion is of great importance.

Materials and methods

Four datasets related to PNI were downloaded from the Gene Expression Omnibus database and used to construct weighted gene co-expression network analysis (WGCNA). The intersection of potential pathways obtained from further correlation and enrichment analyses of different datasets was validated by the coculture model of Schwann cells (SCs), flow cytometry and immunohistochemistry (IHC).

Results

GSE7055 and GSE86544 datasets were brought into the analysis for there were some significant modules related to PNI, while GSE103479 and GSE102238 datasets were excluded for insignificant differences. In total, 13,841 genes from GSE86544 and 10,809 genes from GSE7055 were used for WGCNA. As a consequence, 19 and 26 modules were generated, respectively. The purple module of GSE86544 and the dark gray module of GSE7055 were positively correlated with perineural invasion. Further correlation and enrichment analyses of genes from the two modules suggested that these genes were mainly enriched in cell cycle processes; especially, the terms S/G2/M phase were enriched. Three kinds of cells grew vigorously after coculture with SCs ex vivo. The Ki67 staining of the cervical cancer samples revealed that the Ki67 index of cancer cells surrounding nerves was higher than of those distant ones.

Conclusion

Our work has identified cancer cell proliferation as a common response to neural cancerous microenvironments, proving a foundation for cancer cell colonization and metastasis.

Perineural and lymphovascular invasion predicts for poor prognosis in locally advanced rectal cancer after neoadjuvant chemoradiotherapy and surgery

Background: Perineural invasion (PNI) and lymphovascular invasion (LVI) are associated with poor prognosis in colorectal cancer, but their clinical significance is still controversial for patients with locally advanced rectal cancer (LARC) who had received neoadjuvant chemoradiotherapy (nCRT) and surgical resection. The aim of this study was to confirm the correlation between PNI and/or LVI and clinical prognosis and to further confirm whether PNI and/or LVI can be used as potential prognostic indicators of adjuvant chemotherapy after nCRT and surgery in LARC.

Methods: From February 2002 to December 2012, a total of 181 patients with LARC who had received nCRT and surgical resection were retrospectively reviewed. Overall survival (OS) and disease-free survival (DFS) were determined by the Kaplan-Meier method, log-rank test, and Cox proportional hazard regression model.

Results: The median follow-up time was 48 months (range, 3 to 162 months). All the PNI-positive and/or LVI-positive patients showed adverse DFS and OS (P<0.001). In multivariate analysis, PNI and LVI were independent prognostic factors for DFS. PNI, rather than LVI, was also an independent prognostic factor for OS. In a subgroup analysis, PNI-positive, rather than LVI-positive, may benefit from adjuvant chemotherapy.

Conclusion: For patients with LARC undergoing nCRT and surgery, PNI-positive and/or LVI positive were associated with poorer DFS and OS. And PNI-positive, rather than LVI-positive, may benefit from adjuvant chemotherapy.

Perineural invasion in cervical cancer: pay attention to the indications of nerve-sparing radical hysterectomy

Perineural invasion (PNI) in early-stage cervical cancer, is associated with multiple high-risk factors and represents a poor outcome in the patients. For nerve-sparing radical hysterectomy (NSRH) to become a standard and widely used treatment for cervical cancer, we need to define its oncological safety, and to establish standardized surgical procedures and indications of NSRH. Here, we review the definition and mechanisms, and clinical significance of PNI in cervical cancer, and discuss the indications of NSRH. PNI should be regarded as one of the main pathological features of cervical cancer and a factor affecting prognosis. A deeper understanding of PNI in cervical cancer, hopefully, will provide clear indications of NSRH.

Salivary gland stem cells: A review of development, regeneration and cancer

Salivary glands are responsible for maintaining the health of the oral cavity and are routinely damaged by therapeutic radiation for head and neck cancer as well as by autoimmune diseases such as Sjögren's syndrome. Regenerative approaches based on the reactivation of endogenous stem cells or the transplant of exogenous stem cells hold substantial promise in restoring the structure and function of these organs to improve patient quality of life. However, these approaches have been hampered by a lack of knowledge on the identity of salivary stem cell populations and their regulators. In this review we discuss our current knowledge on salivary stem cells and their regulators during organ development, homeostasis and regeneration. As increasing evidence in other systems suggests that progenitor cells may be a source of cancer, we also review whether these same salivary stem cells may also be cancer initiating cells.

Should reporting of peri-neural invasion and extra prostatic extension be mandatory in prostate cancer biopsies? correlation with outcome in biopsy cases treated conservatively

The identification of perineural invasion (PNI) and extraprostatic extension (ECE) in prostate cancer (PC) biopsies is time consuming and can be difficult. Although this is required information in many datasets, there is little evidence on their effect on outcome in patients treated conservatively. Cases of PC were identified from three cancer registries in the UK from men with clinically localized prostate cancer diagnosed by needle biopsy from 1990-2003. The endpoint was prostate cancer death (DOD). Patients treated radically within 6 months, those with objective evidence of metastases or who had prior hormone therapy were excluded. Follow-up was through cancer registries up until 2012. Deaths were divided into those from PC and those from other causes, according to WHO criteria. 988 biopsy cases (6522 biopsy cores) were centrally reviewed by three uropathologists and assigned a Gleason score and Grade Group (GG). The presence of both PNI and ECE was recorded. Of 988 patients, PNI was present in 288 (DOD = 75) and ECE in 23 (DOD = 5). On univariable analysis PNI was highly significantly associated with DOD (hazard ratio [HR] 2.28, 95% CI: 1.68, 3.1, log-rank test p-value = 4.8 × 10-8), but ECE was not (log-rank test p-value = 0.334). On multivariable analysis with GG, serum PSA (per 10%), clinical stage and extent of disease (per 10%), PNI lost significance (HR 1.16, 95% CI: 0.83, 1.63, likelihood ratio test p-value = 0.371). The utility of routinely examining prostate biopsies for ECE and PNI is doubtful as it is not independently associated with higher grade, stage or prognosis.

Effects of perineural invasion on biochemical recurrence and prostate cancer-specific survival in patients treated with definitive external beam radiotherapy

OBJECTIVES

Perineural invasion (PNI) has not yet gained universal acceptance as an independent predictor of adverse outcomes for prostate cancer treated with external beam radiotherapy (EBRT). We analyzed the prognostic influence of PNI for a large institutional cohort of prostate cancer patients who underwent EBRT with and without androgen deprivation therapy (ADT).

MATERIAL AND METHODS

We, retrospectively, reviewed prostate cancer patients treated with EBRT from 1993 to 2007 at our institution. The primary endpoint was biochemical failure-free survival (BFFS), with secondary endpoints of metastasis-free survival (MFS), prostate cancer-specific survival (PCSS), and overall survival (OS). Univariate and multivariable Cox proportional hazards models were constructed for all survival endpoints. Hazard ratios for PNI were analyzed for the entire cohort and for subsets defined by NCCN risk level. Additionally, Kaplan-Meier survival curves were generated for all survival endpoints after stratification by PNI status, with significant differences computed using the log-rank test.

RESULTS

Of 888 men included for analysis, PNI was present on biopsy specimens in 187 (21.1%). PNI was associated with clinical stage, pretreatment PSA level, biopsy Gleason score, and use of ADT (all P<0.01). Men with PNI experienced significantly inferior 10-year BFFS (40.0% vs. 57.8%, P = 0.002), 10-year MFS (79.7% vs. 89.0%, P = 0.001), and 10-year PCSS (90.9% vs. 95.9%, P = 0.009), but not 10-year OS (67.5% vs. 77.5%, P = 0.07). On multivariate analysis, PNI was independently associated with inferior BFFS (P<0.001), but not MFS, PCSS, or OS. In subset analysis, PNI was associated with inferior BFFS (P = 0.04) for high-risk patients and with both inferior BFFS (P = 0.01) and PCSS (P = 0.05) for low-risk patients. Biochemical failure occurred in 33% of low-risk men with PNI who did not receive ADT compared to 8% for low-risk men with PNI treated with ADT (P = 0.01).

CONCLUSION

PNI was an independently significant predictor of adverse survival outcomes in this large institutional cohort, particularly for patients with NCCN low-risk disease. PNI should be carefully considered along with other standard prognostic factors when treating these patients with EBRT. Supplementing EBRT with ADT may be beneficial for select low-risk patients with PNI though independent validation with prospective studies is recommended.

Perineural invasion in early-stage cervical cancer and its relevance following surgery

Perineural invasion (PNI) is the neoplastic invasion of nerves by cancer cells, a process that has attracted attention as a novel prognostic factor for cancer. The present study aimed to investigate the prognostic value of PNI in patients with early-stage cervical cancer (International Federation of Gynecology and Obstetrics stage IA2-IIA). A total of 210 patients who underwent radical hysterectomy and pelvic lymphadenectomy between 2007 and 2012 were included in the current study, of whom 8.57% (18/210) exhibited PNI. Patients with PNI were more likely to exhibit adverse histopathological features, such as increased tumor size, depth of stromal invasion, parametrial invasion, lymphovascular space invasion and lymph nodes metastases (all P<0.05). Patients with PNI exhibited shorter disease-free and overall survival (P=0.002 and P=0.017, respectively). However, PNI was not identified as an independent risk factor for either recurrence or death by multivariate analysis. Furthermore, 88.9% (16/18) of patients with PNI received adjuvant therapy following surgery. PNI was significantly associated with well-established indicators for adjuvant therapy. In conclusion, PNI was associated with multiple high-risk factors and its presence was indicative of a poor outcome in patients with early-stage cervical cancer, which may influence management decisions regarding adjuvant therapy.

Neural Invasion is a Significant Contributor to Peritoneal Recurrence in Signet Ring Cell Gastric Carcinoma

BACKGROUND

Gastric signet ring cell carcinoma (SRC) has shown a favorable outcome in early stages but has a worse prognosis than non-SRC in advanced stages. However, the cause for this stage-dependent prognostic impact has not been determined. This study aimed to compare clinicopathologic features and recurrence patterns between gastric SRC and non-SRC in a cohort of Eastern patients.

METHODS

This study reviewed the prospectively collected data of 764 patients undergoing curative resection for gastric cancer from 2005 to 2008. The demographics, clinicopathologic characteristics, disease-specific survival (DSS) rate, and recurrence-free survival (RFS) rate of the patients were analyzed.

RESULTS

The SRC patients (n = 176) had a worse prognosis than the non-SRC patients (n = 588), especially in stages T3 and T4. Peritoneal recurrence and the incidence of neural invasion (NI) were significantly increased in the SRC patients, albeit only in stages T3 and T4. In the T3 and T4 patients with NI, peritoneal recurrence occurred more frequently in SRC than in non-SRC (28.7% vs. 13.7%; p = 0.001), but not in the T3 and T4 patients without NI. Only in the patients with NI, SRC led to a significantly shorter DSS (67.6 vs. 90.7 months; p = 0.008) and RFS (67.1 vs. 80.3 months; p = 0.036) than non-SRC.

CONCLUSIONS

This report is the first to present the relationship between NI and peritoneal recurrence as the cause of stage-dependent prognoses for SRC. A better understanding of NI may lend insight into cancer spread and recurrence, especially in gastric SRC.

Quantitative perineural invasion is a prognostic marker in prostate cancer

This study aimed to investigate the prognostic value of a quantitative, detailed, yet practical analysis of perineural invasion in radical prostatectomy specimens in a high-risk prostate cancer cohort. A total of 114 patients with prostate cancer who underwent radical prostatectomy between 2000 and 2013 were analysed. Using S100 protein immunohistochemistry assisted in the detection of nerves. In the area of closest proximity of the tumour to the dorso-lateral margins, nerves were counted and the infiltration of nerves was categorised (0-3). Category 0 was nerves without immediate tumour-cell-contact. All nerves being fully surrounded by tumour (classical perineural carcinosis) were categorised group 3. Two further categories discriminated between nerves that were touched either by carcinoma cells below 50% of the circumference (category 1) or above (category 2). Perineural carcinosis (Pn1) was seen in 61.4% of cases and correlated positively with ISUP grades, pT categories and presence of intraductal carcinoma but failed significance on Kaplan-Meier analysis. A more quantitative analysis of percentual perineural involvement did demonstrate significant survival differences: cases with less than one Pn1-positive nerve in 5 high power fields had longer survival times. Incomplete perineural involvement (category 1-2) did not have a prognostic value, endorsing the current definition of perineural carcinosis as full circumferential encasement of a nerve by tumour cells. A quantitative analysis of the percentage of nerves positive for perineural invasion has a higher prognostic value than the classical dichotomous statement on the mere presence of perineural invasion.

Extramural perineural invasion in pT3 and pT4 rectal adenocarcinoma as prognostic factor after preoperative chemoradiotherapy

Perineural invasion (PNI) is widely studied in malignant tumors, and its prognostic significance is well demonstrated in the head and neck and prostate carcinomas, but its significance in rectal cancer is controversial. Most studies have focused on evaluating mural PNI (mPNI); however, extramural PNI (ePNI) may influence the prognosis after rectal cancer resection. We evaluated the prognostic value of ePNI compared with mPNI and with non-PNI, in rectal resections after preoperative chemoradiotherapy in 148 patients with pT3 and pT4 rectal carcinomas. PNI was identified in 35 patients (23.6%), 60% of which were in the mPNI group. Factors associated with PNI were tumor invasion depth, lymph node metastasis, lymphovascular invasion, and venous invasion; patients with PNI were more likely to have positive resection margins (65.7% versus 11.6%). ePNI, compared with mPNI, was associated with female sex (64.3% versus 28.6%), positive surgical margins (42.8% versus 28.6%), recurrence (50% versus 28.6%), and death (92.9% versus 28.6%). The 5-year disease-specific survival rate was 78.1% for patients without PNI, compared with 63.7% for the mPNI group and 26.4% for the ePNI group (P<.001). On multivariate analysis, the independent adverse prognostic factors were ePNI (odds ratio [OR], 22.17; 95% confidence interval [CI], 17.03-24.58; P<.001), overall recurrence (OR, 9.19; CI, 6.11-10.63; P=.002), clinical stage IV (OR, 8.56; CI, 6.34-9.47; P=.003), and positive surgical margin (OR, 3.95; CI, 2.00-4.28; P=.047). In conclusion, we demonstrated the prognostic effect of ePNI for disease-specific survival in surgically resected pT3-pT4 rectal cancer patients with preoperative chemoradiotherapy.

Perineural Invasion and Risk of Lethal Prostate Cancer

Background: Prostate cancer has a propensity to invade and grow along nerves, a phenomenon called perineural invasion (PNI). Recent studies suggest that the presence of PNI in prostate cancer has been associated with cancer aggressiveness.Methods: We investigated the association between PNI and lethal prostate cancer in untreated and treated prostate cancer cohorts: the Swedish Watchful Waiting Cohort of 615 men who underwent watchful waiting, and the U.S. Health Professionals Follow-Up Study of 849 men treated with radical prostatectomy. One pathologist performed a standardized histopathologic review assessing PNI and Gleason grade. Patients were followed from diagnosis until metastasis or death.Results: The prevalence of PNI was 7% and 44% in the untreated and treated cohorts, respectively. PNI was more common in high Gleason grade tumors in both cohorts. PNI was associated with enhanced tumor angiogenesis, but not tumor proliferation or apoptosis. In the Swedish study, PNI was associated with lethal prostate cancer [OR 7.4; 95% confidence interval (CI), 3.6-16.6; P < 0.001]. A positive, although not statistically significant, association persisted after adjustment for age, Gleason grade, and tumor volume (OR 1.9; 95% CI, 0.8-5.1; P = 0.17). In the U.S. study, PNI predicted lethal prostate cancer independent of clinical factors (HR 1.8; 95% CI, 1.0, 3.3; P =0.04).Conclusions: These data support the hypothesis that perineural invasion creates a microenvironment that promotes cancer aggressiveness.Impact: Our findings suggest that PNI should be a standardized component of histopathologic review, and highlights a mechanism underlying prostate cancer metastasis. Cancer Epidemiol Biomarkers Prev; 26(5); 719-26. ©2017 AACR.

Lymph node or perineural invasion is associated with low miR-15a, miR-34c and miR-199b levels in head and neck squamous cell carcinoma

Background

MicroRNAs (miRNAs or miRs) are post-transcriptional regulators of eukaryotic cells and knowledge of differences in miR levels may provide new approaches to diagnosis and therapy.

Methods

The present study measured the levels of nine miRs in head and neck squamous cell carcinomas (HNSCC) and determined whether clinical pathological features are associated with differences in miR levels. SET (I2PP2A) and PTEN protein levels were also measured, since their levels can be regulated by miR-199b and miR-21, respectively. Nine miRs (miR-15a, miR-21, miR-29b, miR-34c, miR-100, miR-125b, miR-137, miR-133b and miR-199b) were measured by real time qRT-PCR in HNSCC samples from 32 patients and eight resection margins. SET (I2PP2A) and PTEN protein levels were estimated by immunohistochemistry in paired HNSCC tissues and their matched resection margins.

Results

In HNSCC, the presence of lymph node invasion was associated with low miR-15a, miR-34c and miR-199b levels, whereas the presence of perineural invasion was associated with low miR-199b levels. In addition, miR-21 levels were high whereas miR-100 and miR-125b levels were low in HNSCC compared to the resection margins. When HNSCC line HN12, with or without knockdown of SET, were transfected with miR-34c inhibitor or miR-34c mimic, the miR-34c inhibitor increased cell invasion capacity while miR-34c mimic decreased the cell invasion.

Conclusions

We showed that the levels of specific miRs in tumor tissue can provide insight into the maintenance and progression of HNSCC.

General significance

MiRNAs are up- or down-regulated during cancer development and progression; they can be prognosis markers and therapeutic targets in HNSCC.

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Association between miR-15a, miR-34c and miR-199b levels and lymph node metastasis in HNSCC.

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miR-199b is reduced while SET protein is accumulated in HNSCC.

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Levels of miR-34c control invasion in HNSCC.

In Vitro Modeling of Cancerous Neural Invasion: The Dorsal Root Ganglion Model

One way that solid tumors disseminate is through neural invasion. This route is well-known in cancers of the head and neck, prostate, and pancreas. These neurotropic cancer cells have a unique ability to migrate unidirectionally along nerves towards the central nervous system (CNS). The dorsal root ganglia (DRG)/cancer cell model is a three dimensional (3D) in vitro model frequently used for studying the interaction between neural stroma and cancer cells. In this model, mouse or human cancer cell lines are grown in ECM adjacent to preparations of freshly dissociated cultured DRG. In this article, the DRG isolation protocol from mice, and implantation in petri dishes for co-culturing with pancreatic cancer cells are demonstrated. Five days after implantation, the cancer cells made contact with the DRG neurites. Later, these cells formed bridgeheads to facilitate more extensive polarized, neurotropic migration of cancer cells.

Prognostic factors in the patients with T2N0M0 colorectal cancer

BACKGROUND

The 5-year survival rate of the patients with stage I colorectal cancer is about 90%; therefore, adjuvant therapy has not been recommended after radical resection; however, about 16-26% of T2N0M0 patients will be dead at 5 years despite radical curative resection. It indicated that there is a defined group of patients who are at high risk for relapse or metastasis despite radical operation. This study aimed to find the patients with T2N0M0 colorectal cancer at high risk for relapse or metastasis.

METHODS

From January 1993 to December 2014, 812 patients with histologically confirmed stage T2N0M0 primary colorectal cancer treated by radical surgery with complete clinical follow-up data were eligible for this study. The medical records of all patients were collected and were retrospectively analyzed. Survival rates were calculated using Kaplan-Meier method, and survival cures were compared using the log-rank test. Cox proportional hazards model was used to analyze the significant factors defined in univariate test.

RESULTS

The 5-year and 10-year overall survival rates were 81.9 and 67.7%, respectively. Male gender, old age, lymphovascular permeation, perineural invasion, and poor differentiation were associated with low cancer-specific survival rates in Kaplan-Meier analysis. Multivariate analyses revealed old age, lymphovascular permeation, perineural invasion, and poor differentiation as significant independent factors predicting worse prognosis (P < 0.05).

CONCLUSIONS

Old age, lymphovascular permeation, perineural invasion, and poor differentiation are risk factors for the worse prognostic patients with T2N0M0 colorectal patients who would potential benefit from more aggressive therapy.

The presence of lymphovascular and perineural infiltration after neoadjuvant therapy and oesophagectomy identifies patients at high risk for recurrence

Background:

In patients treated for oesophageal cancer the importance of lymphovascular and perineural invasion (PNI) after neoadjuvant therapy has yet to be established. The aim of this study was to assess the incidence and prognostic significance of these factors in a consecutive series of patients with cancer of the oesophagus or gastro-oesophageal junction (GOJ) who underwent neoadjuvant therapy followed by oesophagectomy.

Methods:

Clinical and pathology results from patients with potentially curable adenocarcinoma, or squamous cell carcinoma of the oesophagus or GOJ were reviewed. Patients were treated with neoadjuvant chemotherapy or chemoradiation followed by transthoracic oesophagectomy and two-field lymphadenectomy. The presence of venous invasion (VI), lymph vessel invasion (LI) and perineural invasion (PNI) were correlated with clinical outcomes.

Results:

A total of 396 patients underwent oesophagectomy after neoadjuvant therapy for oesophageal cancer. Venous invasion was identified in 150 (38%) of patients, LI in 203 (51%) patients and PNI in 204 (52%) patients. In all, 123 (31%) patients had no evidence of either VI, LI or PNI. A total of 96 (24%) had a combination of two factors and 94 (24%) had all three factors. The presence of VI, LI and PNI was significantly related to tumour stage (P=0.001). Median overall survival was 170.8 months when all three factors were absent, 44.0 months when one factor was present, 27.1 months when two factors were present and 16.0 months when all were present. Multivariate analyses revealed VI, LI and PNI or a combination of these factors were independent predictors of prognosis.

Conclusions:

In oesophageal cancer patients treated with neoadjuvant therapy followed by oesophagectomy the presence of VI, LI and PNI has an important prognostic impact and may identify patients at high risk of recurrence who would benefit from adjuvant therapies.

Perineural invasion correlates with postoperative distant metastasis and poor overall survival in patients with PT1-3N0M0 esophageal squamous cell carcinoma

The aim of this study was to determine the prognostic value of perineural invasion (PNI) in patients with PT1-3N0M0 esophageal squamous cell carcinoma (ESCC) who underwent curative resection. A total of 148 patients with PT1-3N0M0 ESCC, who underwent surgery in Zhejiang Cancer Hospital (Hangzhou, People's Republic of China), between 2006 and 2009, were evaluated in this retrospective study. The effects of PNI on distant metastasis-free survival (DMFS) and overall survival (OS) were assessed using Kaplan-Meier analysis. Independent prognostic factors were identified by multivariate Cox analysis. Positive PNI was identified in 25.0% of all the cases. The depth of invasion (PT stage) was closely associated with the PNI positivity (P<0.001). The 5-year DMFS rate and OS rate of the PNI-positive patients were significantly worse than those of the PNI-negative patients (DMFS: 37.2% vs 62.3%, P=0.009; OS: 31.3% vs 74.3%, P,0.001). Multivariate analysis indicated that the positivity of PNI was an independent prognostic factor for both DMFS (hazard ratio [HR] =2.35, P=0.039) and OS (HR =3.56, P=0.002). Our results suggest that PNI was a predictor of distant metastasis and independently associated with prognosis of patients with PT1-3N0M0 ESCC.

Perineural Invasion Is an Independent Pathologic Indicator of Recurrence in Vulvar Squamous Cell Carcinoma

OBJECTIVES

Vulvar squamous cell carcinoma (vSCC) is a gynecologic malignancy diagnosed in nearly 4500 women in the United States each year. Current criteria for treatment planning provide inadequate assessment of aggressive vSCC cases, resulting in insufficient use of adjuvant treatments and high rates of vSCC recurrence. Perineural invasion (PNI) is a pathologic feature inconsistently included in the assessment of vSCC, because its relevance to clinical outcomes in these women is not well defined. The purpose of this study was to determine the association between PNI and relevant clinical parameters such as recurrence.

METHODS

A total of 103 cases of vSCC were evaluated for PNI using pathology report review and immunohistochemistry dual-chromogen staining for S100 and AE1/3. Medical records were reviewed for clinical and follow-up data. Data were analyzed using univariate and multivariate logistic regression statistical methods.

RESULTS

Patients with vSCC containing PNI had a greater risk for cancer recurrence than those whose tumors did not contain PNI (odds ratio=2.8, P=0.0290). There was no significant correlation between the presence of PNI and nodal involvement, stage, or lymphovascular invasion. Tumors with PNI had greater depth of invasion (DOI) (P=0.0047); however, DOI was not associated with recurrence (P=0.2220). When analyzed using a multivariable logistic regression model, PNI was an independent predictor of recurrence in vSCC (adjusted odds ratio=2.613, P=0.045).

CONCLUSIONS

PNI is an independent indicator of risk for recurrence in vSCC. The association of PNI with increased risk for recurrence, independent of DOI, nodal involvement, lymphovascular invasion, or stage, should encourage practicing pathologists to thoroughly search for and report the presence of PNI in vSCC.

Adjuvant chemotherapy for the perineural invasion of colorectal cancer

BACKGROUND

To evaluate the association of perineural invasion (PNI) with outcomes in patients after colorectal resection of colorectal cancer (CRC) and to assess the effect of PNI on the response to adjuvant chemotherapy.

PATIENTS AND METHODS

Data were retrospectively reviewed for 178 patients with consecutive stages I-III CRC who underwent curative surgery between January 1999 and December 2004. PNI data were examined, and the overall survival (OS) and disease-free survival rates were analyzed.

RESULTS

PNI was detected in 36 of 178 patients (20%) and positively correlated with lymphatic invasion (P = 0.020), venous invasion (P = 0.037), and the incidence of metastasis or recurrence (P = 0.029). Five-year disease-free survival was 46% and 68% (P < 0.001) and the 5-y OS was 64% and 80% (P < 0.001) for patients with and without PNI, respectively. In stage III CRC, multiple regression analysis identified PNI as a strong negative prognostic factor of OS; among PNI-positive patients, median OS with adjuvant chemotherapy was almost twofold higher than that without adjuvant chemotherapy (6 versus 2.8 y; P = 0.017).

CONCLUSIONS

PNI was a poor predictor of survival among patients with stage III CRC, and adjuvant chemotherapy may attenuate the adverse effects of PNI on survival.

Prognostic significance of the concomitant existence of lymphovascular and perineural invasion in locally advanced gastric cancer patients who underwent curative gastrectomy and adjuvant chemotherapy

OBJECTIVE

In this study, we evaluated the prognostic significance of the concomitant existence of lymphovascular invasion and perineural invasion in patients with advanced gastric cancer.

METHODS

A total of 206 consecutive patients with Stage II or III gastric cancer who underwent curative D2 gastrectomy and adjuvant chemotherapy from April 2004 to December 2011 were analyzed. Patients were classified into four groups according to the presence (+) or absence (-) of lymphovascular invasion and perineural invasion: lymphovascular invasion-/perineural invasion- (n = 33), lymphovascular invasion+/perineural invasion- (n = 31), lymphovascular invasion-/perineural invasion+ (n = 54) and lymphovascular invasion+/perineural invasion+ (n = 88).

RESULTS

A total of 136 patients (66.0%) received 5-fluorouracil plus cisplatin adjuvant chemotherapy and 70 patients (34.0%) received TS-1. During the median follow-up period of 35.18 months, the median disease-free survival times for lymphovascular invasion-/perineural invasion-, lymphovascular invasion+/perineural invasion- and lymphovascular invasion-/perineural invasion+ were not reached at the time of analysis; however, median disease-free survival for lymphovascular invasion+/perineural invasion+ was the worst (36.73 months, P = 0.001). The median overall survival in the four groups was also not reached at the time of analysis; however, median overall survival with lymphovascular invasion+/perineural invasion+ was the poorest (P = 0.002). In a multivariate analysis, lymphovascular invasion+/perineural invasion+ was an independent prognostic factor for both disease-free survival (hazard ratio = 1.940, 95% confidence interval 1.157-3.252, P = 0.012) and overall survival (hazard ratio = 2.973, 95% confidence interval 1.561-5.662, P = 0.001).

CONCLUSIONS

The concomitant existence of lymphovascular and perineural invasion has a significant prognostic impact on disease-free survival and overall survival in patients with Stage II or III gastric cancer.

Perineural invasion as a prognostic factor for cervical cancer: a systematic review and meta-analysis

BACKGROUND

Recent observational studies have reported that perineural invasion (PNI) may be a negative prognostic factor in cervical cancer.

OBJECTIVES

The purpose of this meta-analysis is to systematically analyse the effect of PNI on overall survival and disease-free survival.

SEARCH STRATEGY

The PubMed and Cochrane clinical trials databases were searched for articles with publication dates up to September 2013.

SELECTION CRITERIA

Retrospective observational studies with survival analysis for perineural invasion after radical hysterectomy plus lymphadenectomy of cervical cancer were selected.

DATA COLLECTION AND ANALYSIS

Trial characteristics and outcomes and quality measures based on the Newcastle-Ottawa scale (NOS) were independently extracted. The overall survival and disease-free survival of patients with PNI were measured using a hazard ratio (HR) for time to event outcomes.

MAIN RESULTS

The meta-analysis of these studies demonstrated that cervical cancer with PNI was associated with a lower overall survival rate (HR 2.21, 95 % CI 1.36-3.59, P = 0.001). Although the disease-free survival was lower in the PNI group (HR 1.35, 95 % CI 0.78-2.31, P = 0.28), the results were not statistically significant.

CONCLUSION

Patients with PNI-positive cervical cancer have a poor overall survival rate; therefore, we can conclude that perineural invasion (PNI) is an adverse prognostic factor in cervical cancer. Based on these results, PNI should be an independent prognostic factor for cervical cancer and the decision to proceed with adjuvant therapy after surgery.

Downregulation of p53 promotes in vitro perineural invasive activity of human salivary adenoid cystic carcinoma cells through epithelial-mesenchymal transition-like changes

Salivary adenoid cystic carcinoma (SACC) is a malignant tumor that is characterized by perineural invasion (PNI). p53 is an essential tumor-suppressor gene and p53 mutations play a critical role in tumor occurrence and progression (e.g., pancreatic, prostate and head and neck cancer). However, the regulatory role of the p53 gene in SACC and the PNI process remains unknown. In the present study, we employed RNA interference technique to downregulate p53 gene expression in SACC-83 cells to explore the role of p53 in the PNI process. Our results showed that the downregulation of the p53 gene induced significant 'epithelial-mesenchymal transition (EMT)-like changes' in SACC-83 cells, including decreased expression levels of epithelial markers (E-cadherin, EMA and CK5) and increased expression levels of mesenchymal markers (vimentin, N-cadherin and C-cadherin). The downregulation of p53 also caused a lower apoptotic index of Annexin V-FITC/PI and a lower number of SACC-83 cells in the second G0/G1 phase of the cell cycle. Furthermore, the downregulation of the p53 gene resulted in a significant increase in PNI activity in the SACC-83 cells. Thus, our findings revealed that downregulation of p53 promoted in vitro PNI activity through 'EMT-like changes' in SACC-83 cells. The present study suggests the essential regulatory role of p53 in the PNI activity of SACC cells, and implies that p53 may be a new target gene for the clinical treatment of SACC.

The clinicopathological significance of neurogenesis in breast cancer

Background

Recent reports support a novel biological phenomenon about cancer related neurogenesis. However, little is known about the clinicopathological significance of neurogenesis in breast cancer.

Methods

A total of 196 cases, including 20 of normal tissue, 14 of fibroadenoma, 18 of ductal carcinoma in situ (DCIS) and 144 of invasive ductal carcinoma (IDC) of the breast were used. The tissue slides were immunostained for protein gene product (PGP) 9.5 and S 100 to identify nerves. The correlation between the expression of PGP 9.5 and clinicopathological characteristics in IDC of the breast was assessed.

Results

While the PGP 9.5 positive nerve fibers are identified in all cases of normal breast tissue controls and in the tumor stroma of 61% (89/144) cases of invasive ductal carcinomas, PGP 9.5 positive nerve fibers are not seen in the tumor stroma of cases of fibroadenoma and DCIS. The percentage of tumors that exhibited neurogenesis increased from tumor grade I to tumor grade II and III (29.4% vs 71.8%, p < 0.0001). In addition, patients with less than 3 years of disease-free survival tended to have a higher positive expression of PGP 9.5 compared to patients with an equal or more than 3 years of disease-free survival (64.8% vs 46.7%, p = 0.035). Furthermore, moderate/strong expression of PGP 9.5 was found to be significantly related to microvessel density (MVD, p = 0.014). Interestingly, PGP 9.5 expression was significantly associated with higher MVD in the ER-negative (p = 0.045) and node-negative (p = 0.039) subgroups of IDC of the breast.

Conclusions

This data indicates that neurogenesis is associated with some aggressive features of IDC including tumor grade and patient survival as well as angiogenesis, especially in ER-negative and node-negative subtypes of IDC of the breast. Thus, neurogenesis appears to be associated with breast cancer progression and may play a role in therapeutic guidance for patients with ER-negative and node-negative invasive breast cancer.

GFRα1 released by nerves enhances cancer cell perineural invasion through GDNF-RET signaling

The ability of cancer cells to invade along nerves is associated with aggressive disease and diminished patient survival rates. Perineural invasion (PNI) may be mediated by nerve secretion of glial cell line-derived neurotrophic factor (GDNF) attracting cancer cell migration through activation of cell surface Ret proto-oncogene (RET) receptors. GDNF family receptor (GFR)α1 acts as coreceptor with RET, with both required for response to GDNF. We demonstrate that GFRα1 released by nerves enhances PNI, even in the absence of cancer cell GFRα1 expression. Cancer cell migration toward GDNF, RET phosphorylation, and MAPK pathway activity are increased with exposure to soluble GFRα1 in a dose-dependent fashion. Dorsal root ganglia (DRG) release soluble GFRα1, which potentiates RET activation and cancer cell migration. In vitro DRG coculture assays of PNI show diminished PNI with DRG from GFRα1(+/-) mice compared with GFRα1(+/+) mice. An in vivo murine model of PNI demonstrates that cancer cells lacking GFRα1 maintain an ability to invade nerves and impair nerve function, whereas those lacking RET lose this ability. A tissue microarray of human pancreatic ductal adenocarcinomas demonstrates wide variance of cancer cell GFRα1 expression, suggesting an alternate source of GFRα1 in PNI. These findings collectively demonstrate that GFRα1 released by nerves enhances PNI through GDNF-RET signaling and that GFRα1 expression by cancer cells enhances but is not required for PNI. These results advance a mechanistic understanding of PNI and implicate the nerve itself as a key facilitator of this adverse cancer cell behavior.

Variation in reporting of cancer extent and benign histology in prostate biopsies among European pathologists

It is not known how uropathologists currently report histopathological features of prostate biopsies such as core length, tumor extent, perineural invasion, and non-tumor-associated features such as inflammation and hyperplasia in needle biopsies. A web-based survey was distributed among 661 members of the European Network of Uropathology. Complete replies were received from 266 pathologists in 22 European countries. Total core lengths were reported by 64 %. The numbers of cores positive for cancer was given by 79 %. Linear cancer extent was reported by 81 %, most often given in millimeters for each core (53 %) followed by the estimation of percentage of cancer in each core (40 %). A gap of benign tissue between separate cancer foci in a single core would always be subtracted by 48 % and by 63 % if cancer foci were minute and widely separated. Perineural invasion was reported by 97 %. Fat invasion by tumor was interpreted as extraprostatic extension by 81 %. Chronic and active/acute inflammation was always reported by 32 and 56 % but only if pronounced by 54 and 39 %, respectively. While most (79 %) would never diagnose benign prostatic hyperplasia on needle biopsy, 21 % would attempt to make this diagnosis. Reporting practices for prostate biopsies are variable among European pathologists. The great variation in some methodologies used suggests a need for further international consensus, in order for retrospective data to be comparable between different institutions.

Oral carcinoma with perineural invasion has higher nerve growth factor expression and worse prognosis

BACKGROUND

This study elucidated the association between histopathological factors and the prognosis of oral carcinoma. As the histopathological factors were determined from the surgical specimen and this can only be used for the choices of postoperative regimens, this study also investigated the linkage between prognostic factors and the expression of key molecules to examine the feasibility of markers as predictors.

METHODS

Clinicopathological factors of 101 oral carcinomas were cross-analyzed with disease-free survival. The expression of nerve growth factor (NGF) and its receptor, tyrosine kinase A receptor, was assayed with immunohistochemistry.

RESULTS

Nodal metastasis was the most crucial clinical predictor for disease-free survival. Perineural invasion (PNI) was an independent histopathological predictor for both nodal metastasis (P = 0.004) and disease-free survival (P = 0.019). Patients with advanced tumor and PNI exhibited the high hazard for tumor progression and poor disease-free survival. NGF immunoreactivity in tumors was correlated with PNI (P = 0.005) and neck lymph node metastasis (P = 0.036).

CONCLUSION

Perineural invasion is the indicator of worst prognosis. As NGF immunoreactivity was found to be associated with PNI and nodal metastasis, the NGF immunoreactivity of oral carcinoma revealed by diagnostic biopsy suggests that alternative therapeutic approaches might be appropriate.

The severity of neural invasion is associated with shortened survival in colon cancer

PURPOSE

Neural invasion (NI) is a histopathologic feature of colon cancer that receives little consideration. Therefore, we conducted a morphologic and functional characterization of NI in colon cancer.

EXPERIMENTAL DESIGN

NI was investigated in 673 patients with colon cancer. Localization and severity of NI was determined and related to patient's prognosis and survival. The neuro-affinity of colon cancer cells (HT29, HCT-116, SW620, and DLD-1) was compared with pancreatic cancer (T3M4 and SU86.86) and rectal cancer cells (CMT-93) in the in vitro three-dimensional (3D)-neural-migration assay and analyzed via live-cell imaging. Immunoreactivity of the neuroplasticity marker GAP-43, and the neurotrophic-chemoattractant factors Artemin and nerve growth factor (NGF), was quantified in colon cancer and pancreatic cancer nerves. Dorsal root ganglia of newborn rats were exposed to supernatants of colon cancer, rectal cancer, and pancreatic cancer cells and neurite density was determined.

RESULTS

NI was detected in 210 of 673 patients (31.2%). Although increasing NI severity scores were associated with a significantly poorer survival, presence of NI was not an independent prognostic factor in colon cancer. In the 3D migration assay, colon cancer and rectal cancer cells showed much less neurite-targeted migration when compared with pancreatic cancer cells. Supernatants of pancreatic cancer and rectal cancer cells induced a much higher neurite density than those of colon cancer cells. Accordingly, NGF, Artemin, and GAP-43 were much more pronounced in nerves in pancreatic cancer than in colon cancer.

CONCLUSION

NI is not an independent prognostic factor in colon cancer. The lack of a considerable biologic affinity between colon cancer cells and neurons, the low expression profile of colonic nerves for chemoattractant molecules, and the absence of a major neuroplasticity in colon cancer may explain the low prevalence and impact of NI in colon cancer.

Neurogenesis in colorectal cancer is a marker of aggressive tumor behavior and poor outcomes

BACKGROUND

Colorectal cancer staging criteria do not rely on examination of neuronal tissue. The authors previously demonstrated that perineural invasion is an independent prognostic factor of outcomes in colorectal cancer. For the current study, they hypothesized that neurogenesis occurs in colorectal cancer and portends an aggressive tumor phenotype.

METHODS

In total, samples from 236 patients with colorectal cancer were used to create a tissue array and database. Tissue array slides were immunostained for protein gene product 9.5 (PGP9.5) to identify nerve tissue. The correlation between markers of neurogenesis and oncologic outcomes was determined. The effect of colorectal cancer cells on stimulating neurogenesis in vitro was evaluated using a dorsal root ganglia coculture model.

RESULTS

Patients whose tumors exhibited high degrees of neurogenesis had 50% reductions in 5-year overall survival and disease-free survival compared with patients whose tumors contained no detectable neurogenesis (P = .002 and P = .006, respectively). Patients with stage II disease and high degrees of neurogenesis had greater reductions in 5-year overall survival and disease-free survival compared with lymph node-negative patients with no neurogenesis (P = .002 and P = .008, respectively). Patients with stage II disease and high degrees of neurogenesis had lower 5-year overall survival and disease-free survival compared with patients who had stage III disease with no neurogenesis (P = .01 and P = .008, respectively). Colorectal cancer cells stimulated neurogenesis and exhibited evidence of neuroepithelial interactions between nerves and tumor cells in vitro.

CONCLUSIONS

Neurogenesis in colorectal cancer appeared to play a critical role in colorectal cancer progression. Furthermore, the current results indicated that neurogenesis functions as an independent predictor of outcomes and may play a role in therapy stratification for patients with lymph node-negative disease.

Perineural invasion predicts increased recurrence, metastasis, and death from prostate cancer following treatment with dose-escalated radiation therapy

PURPOSE

To assess the prognostic value of perineural invasion (PNI) for patients treated with dose-escalated external-beam radiation therapy for prostate cancer.

METHODS AND MATERIALS

Outcomes were analyzed for 651 men treated for prostate cancer with EBRT to a minimum dose ≥75 Gy. We assessed the impact of PNI as well as pretreatment and treatment-related factors on freedom from biochemical failure (FFBF), freedom from metastasis (FFM), cause-specific survival (CSS), and overall survival.

RESULTS

PNI was present in 34% of specimens at biopsy and was significantly associated with higher Gleason score (GS), T stage, and prostate-specific antigen level. On univariate and multivariate analysis, the presence of PNI was associated with worse FFBF (hazard ratio = 1.7, p <0.006), FFM (hazard ratio = 1.8, p <0.03), and CSS (HR = 1.4, p <0.05) compared with absence of PNI; there was no difference in overall survival. Seven-year rates of FFBF, FFM, and CCS were 64% vs. 80%, 84% vs. 92%, and 91% vs. 95% for those patients with and without PNI, respectively. On recursive partitioning analysis, PNI predicted for worse FFM and CSS in patients with GS 8-10, with FFM of 67% vs. 89% (p <0.02), and CSS of 69% vs. 91%, (p <0.04) at 7 years for those with and without PNI, respectively.

CONCLUSIONS

The presence of PNI in the prostate biopsy predicts worse clinical outcome for patients treated with dose-escalated external-beam radiation therapy. Particularly in patients with GS 8-10 disease, the presence of PNI suggests an increased risk of metastasis and prostate cancer death.

Prognostic factors for the development of biochemical recurrence after radical prostatectomy

Prostate cancer is one of the most common cancers in Western countries and is associated with a considerable risk of mortality. Biochemical recurrence following radical prostatectomy is a relatively common finding, affecting approximately 25% of cases. The aim of our paper was to identify factors that can predict the occurrence of biochemical recurrence, so the patient can be properly counselled pre- and postoperatively. Medline review of the literatures was done followed by a group discussion on the chosen publications and their valuable influence. Preoperative serum total PSA and clinical stage, together with prostatectomy Gleason grade, tumour volume, and perineural and vascular invasions, were the most important variables found to influence outcome.

Invasion of the hypoglossal nerve by adenoid cystic carcinoma of the tongue: case report and review of the literature

Adenoid cystic carcinoma (ACC) is a rare but highly aggressive malignancy mainly originating from the salivary glands. ACC is well known for its propensity toward neural invasion (NI). NI is the process of neoplastic invasion in and along nerves. It is a distinct and well-documented phenomenon in ACC; however, it is an underestimated route of metastatic spread. Multiple distant metastases can be established through NI route, and NI is believed to portend a poor prognosis. Despite increasing recognition of NI in many malignancies, the molecular mechanism behind NI is not well established. We present a unique case of hypoglossal nerve invasion by ACC arising from the minor salivary glands in the tongue of a 34-year-old man. We also review and discuss current theories on the pathogenesis and mechanism of NI.

The severity of neural invasion is a crucial prognostic factor in rectal cancer independent of neoadjuvant radiochemotherapy

OBJECTIVE

To provide a comprehensive characterization of neural invasion (NI) in rectal adenocarcinoma (RC), to establish a novel NI-severity scoring system, and to assess the prognostic value of NI with emphasis on its localization and severity.

BACKGROUND

The literature merely contains small-scale studies with limited histopathological characterization of NI in RC.

METHODS

Neural invasion was thoroughly characterized in 296 patients with locally advanced uT3-RC (139 with primary resection and 157 with neoadjuvant radiochemotherapy [nRCTx]). To identify the precise localization of NI, we investigated the main tumor, peritumoral area, adjacent normal tissue, and all lymph nodes. To classify the clinical impact of NI, an NI severity score was established and related to patient prognosis.

RESULTS

Neural invasion was detected in 32% of patients with primary resection and in 19% (P = 0.010) receiving nRCTx. The major location of NI was found in the peritumoral area. The prevalence of NI in the main tumor within the primary resection group was 6%, whereas it was absent in the nRCTx group (P = 0.002). Increasing NI severity, but not NI localization, was associated with a significantly poorer survival and increased local recurrence rate in both groups. Multivariate analysis (including TNM-stage, grading, and Carcinoembryonic antigen (CEA)) revealed NI prevalence and severity as independent prognostic factors.

CONCLUSIONS

Neural invasion in RC has a heterogeneous appearance in regard to its localization and its severity. nRCTx seems to have a suppressive effect on NI. Neural invasion severity might be applied as a novel tool to estimate accurately patient's prognosis and thus should be considered in pathology reports.