-
Journal of Neurological Surgery. Part... Apr 2016We present a review of the imaging findings of large nerve perineural spread within the skull base. The MRI techniques and reasons for performing different sequences are... (Review)
Review
We present a review of the imaging findings of large nerve perineural spread within the skull base. The MRI techniques and reasons for performing different sequences are discussed. A series of imaging examples illustrates the appearance of perineural tumor spread with an emphasis on the zonal staging system.
PubMed: 27123387
DOI: 10.1055/s-0036-1571836 -
Biomedical Papers of the Medical... Dec 2019Oral squamous cell carcinoma (OSCC) is a growing problem worldwide. Several biological and molecular criteria have been established for making a prognosis of OSCC. One...
Oral squamous cell carcinoma (OSCC) is a growing problem worldwide. Several biological and molecular criteria have been established for making a prognosis of OSCC. One of the most important factors affecting the risk of tumor recurrence and overall prognosis is perineural invasion and bone invasion. Perineural invasion is defined as a tumor spreading and the ability of tumor cells to penetrate around or through the nerve tissue. Perineural invasion can cause the tumor to spread to distant areas from the primary tumor location. One possible explanation for this is the formation of microenvironment in the perineural space which may contain cellular factors that act on both nerve tissue and some types of tumor tissues. Bone invasion by OSCC has major implications for tumor staging, choice of treatment, outcome and quality of life. Oral SCCs invade the mandibular or maxillary bone through an erosive, infiltrative or mixed pattern that correlates with clinical behavior. Bone resorption by osteoclasts is an important step in the process of bone invasion by oral SCCs. Some cytokines (e.g. TNFα and PTHrP) lead to receptor activator of NF-κB ligand (RANKL) expression or osteoprotegerin (OPG) suppression in oral SCC cells and in cancer stromal cells to induce osteoclastogenesis. Oral SCCs provide a suitable microenvironment for osteoclastogenesis to regulate the balance of RANKL and OPG. A more molecular-based clinical staging and tailor-made therapy would benefit patients with bone invasion by OSCC.
Topics: Adult; Aged; Aged, 80 and over; Biomarkers, Tumor; Bone Neoplasms; Carcinoma, Squamous Cell; Cytokines; Female; Humans; Male; Middle Aged; Mouth Neoplasms; Neoplasm Invasiveness; Neoplasm Recurrence, Local; Nerve Sheath Neoplasms; Predictive Value of Tests; Prognosis
PubMed: 31435075
DOI: 10.5507/bp.2019.032 -
Insights Into Imaging Aug 2018Meckel's cave is a dural recess in the posteromedial portion of the middle cranial fossa that acts as a conduit for the trigeminal nerve between the prepontine cistern... (Review)
Review
UNLABELLED
Meckel's cave is a dural recess in the posteromedial portion of the middle cranial fossa that acts as a conduit for the trigeminal nerve between the prepontine cistern and the cavernous sinus, and houses the Gasserian ganglion and proximal rootlets of the trigeminal nerve. It serves as a major pathway in perineural spread of pathologies such as head and neck neoplasms, automatically upstaging tumours, and is a key structure to assess in cases of trigeminal neuralgia. The purpose of this pictorial review is threefold: (1) to review the normal anatomy of Meckel's cave; (2) to describe imaging findings that identify disease involving Meckel's cave; (3) to present case examples of trigeminal and non-trigeminal processes affecting Meckel's cave.
TEACHING POINTS
• Meckel's cave contains the trigeminal nerve between prepontine cistern and cavernous sinus. • Assessment is essential for perineural spread of disease and trigeminal neuralgia. • Key imaging: neural enhancement, enlargement, perineural fat/CSF effacement, skull base foraminal changes.
PubMed: 29671218
DOI: 10.1007/s13244-018-0604-7 -
Magnetic Resonance Imaging Clinics of... Feb 2022Perineural tumor spread (PNTS) is one of the important methods of tumoral spread in head and neck cancers. It consists of a complex process that entails the production... (Review)
Review
Perineural tumor spread (PNTS) is one of the important methods of tumoral spread in head and neck cancers. It consists of a complex process that entails the production of certain chemicals or the production of certain cell receptors. Histologic type and primary tumor site play an important role in PNTS. Any nerve could be affected; however, the trigeminal and facial nerves are the most involved nerves. Magnetic resonance imaging and computed tomography detect the primary and secondary signs of PNTS. Functional imaging such as diffusion-weighted imaging and hybrid imaging act as problem-solving techniques.
Topics: Head and Neck Neoplasms; Humans; Magnetic Resonance Imaging; Neoplasm Invasiveness; Tomography, X-Ray Computed
PubMed: 34802584
DOI: 10.1016/j.mric.2021.06.017 -
Journal of Neurological Surgery. Part... Apr 2016We present a review of the imaging surveillance following treatment for large nerve perineural spread in the skull base. The expected appearance and possible... (Review)
Review
We present a review of the imaging surveillance following treatment for large nerve perineural spread in the skull base. The expected appearance and possible complications following surgery and radiotherapy are discussed. Imaging examples of the possible sites of disease recurrence are also presented.
PubMed: 27123395
DOI: 10.1055/s-0036-1571840 -
Insights Into Imaging Aug 2016The pterygopalatine fossa (PPF) is a small, clinically inaccessible, fat-filled space located in the deep face that serves as a major neurovascular crossroad between the... (Review)
Review
UNLABELLED
The pterygopalatine fossa (PPF) is a small, clinically inaccessible, fat-filled space located in the deep face that serves as a major neurovascular crossroad between the oral cavity, nasal cavity, nasopharynx, orbit, masticator space, and the middle cranial fossa. Due to its inherent complex location and connections, it can potentially act as a natural conduit for the spread of inflammatory and neoplastic diseases across the various deep spaces in the head and neck. This review aims to acquaint the reader with the imaging anatomy of the PPF, its important communications, and to identify some major pathological conditions that can involve the PPF, especially in conditions where its involvement can have serious diagnostic and therapeutic implications, such as in perineural tumour spread.
TEACHING POINTS
• The PPF is a small neurovascular junction in the deep face with important to-and-fro connections. • Awareness of anatomy of the PPF and its communications helps to simplify imaging of its pathology. • Perineural tumour spread is clinically the most important pathology in this region.
PubMed: 27230518
DOI: 10.1007/s13244-016-0498-1 -
Anticancer Research Aug 2016To identify differentially expressed genes (DEGs) between perineural invasion-positive (PP) and -negative (PN) cutaneous squamous cell cancers (CSCC).
AIM
To identify differentially expressed genes (DEGs) between perineural invasion-positive (PP) and -negative (PN) cutaneous squamous cell cancers (CSCC).
MATERIALS/METHODS
Forty CSCC samples with and without perineural invasion were processed for RNA isolation and hybridization to Affymetrix-U219 DNA microarrays. Raw gene expression data were normalized by Robust Multi-array Averaging (RMA) and log2 transformed. Gene expression-based classification models were created and accuracies evaluated using leave-one-out cross-validation.
RESULTS
At a stringent limma p-value (p<0.001), 24 genes were differentially expressed between PP and PN samples. The cross-validated performance of the eight classification models exhibited a mean accuracy of 85-95%. Diagonal linear discriminant was most accurate at 95%, followed by Bayesian compound covariate at 94%. The poorest accuracy (85%) was observed for 1-Nearest neighbor and Support vector machines.
CONCLUSION
Gene expression may distinguish between PP and PN CSCC. Understanding these gene patterns may potentiate more timely diagnosis of perineural invasion and guide comprehensive therapies.
Topics: Bayes Theorem; Biomarkers, Tumor; Epithelial Cells; Gene Expression Regulation, Neoplastic; Humans; Neoplasm Invasiveness; Neoplasm Proteins; Neoplasms, Squamous Cell; Nerve Sheath Neoplasms; Oligonucleotide Array Sequence Analysis; Skin Neoplasms; Support Vector Machine
PubMed: 27466506
DOI: No ID Found -
Insights Into Imaging Dec 2018Perineural tumour spread (PNTS) in head and neck oncology is most often caused by squamous cell carcinoma. The most frequently affected nerves are the trigeminal and... (Review)
Review
Perineural tumour spread (PNTS) in head and neck oncology is most often caused by squamous cell carcinoma. The most frequently affected nerves are the trigeminal and facial nerves. Up to 40% of patients with PNTS may be asymptomatic. Therefore, the index of suspicion should be high when evaluating imaging studies of patients with head and neck cancer. This review describes a "quick search checklist" of easily detected imaging signs of PNTS. TEACHING POINTS: • A distinctive feature of head and neck tumours is growth along nerves. • Perineural tumour spread is most often caused by squamous cell carcinoma. • There are several key findings for the detection of perineural tumour spread.
PubMed: 30446949
DOI: 10.1007/s13244-018-0672-8 -
Regional Anesthesia and Pain Medicine Jun 2022This randomized trial compared perineural dexamethasone with combined perineural dexamethasone-dexmedetomidine for ultrasound-guided infraclavicular block. We...
BACKGROUND
This randomized trial compared perineural dexamethasone with combined perineural dexamethasone-dexmedetomidine for ultrasound-guided infraclavicular block. We hypothesized that the combination of perineural adjuvants would result in a longer motor block.
METHODS
Fifty patients undergoing upper limb surgery with ultrasound-guided infraclavicular block (using 35 mL of lidocaine 1%-bupivacaine 0.25% with epinephrine 5 µg/mL) were randomly allocated to receive perineural dexamethasone (2 mg) or combined perineural dexamethasone (2 mg)-dexmedetomidine (50 µg). After the performance of the block, a blinded observer assessed the success rate (defined as a minimal sensorimotor composite score of 14 out of 16 points at 30 min), the onset time (defined as the time required to reach a minimal composite score of 14 points) as well as the incidence of surgical anesthesia (defined as the ability to complete surgery without local infiltration, supplemental blocks, intravenous opioids or general anesthesia).Postoperatively, the blinded observer contacted patients with successful blocks to inquire about the duration of motor block, sensory block and postoperative analgesia.
RESULTS
No intergroup differences were observed in terms of success rate, onset time and surgical anesthesia. Compared with dexamethasone alone, combined dexamethasone-dexmedetomidine provided longer durations of motor block (21.5 (2.7) vs 17.0 (3.9) hours; p<0.001; 95% CI 2.6 to 6.4), sensory block (21.6 (3.6) vs 17.2 (3.6) hours; p<0.001; 95% CI 2.2 to 6.5), and postoperative analgesia (25.5 (9.4) vs 23.5 (5.6) hours; p=0.038; 95% CI 1.0 to 7.7).
CONCLUSION
Compared with perineural dexamethasone (2 mg) alone, combined perineural dexamethasone (2 mg)-dexmedetomidine (50 µg) results in longer durations of sensorimotor block and analgesia. Further studies are required to determine the optimal dosing combination for dexamethasone-dexmedetomidine.
TRIAL REGISTRATION NUMBER
ClinicalTrials.gov identifier: NCT04875039.
PubMed: 35728840
DOI: 10.1136/rapm-2022-103760 -
Cancers Feb 2023Perineural invasion (PNI) as the fourth way for solid tumors metastasis and invasion has attracted a lot of attention, recent research reported a new point that PNI... (Review)
Review
Perineural invasion (PNI) as the fourth way for solid tumors metastasis and invasion has attracted a lot of attention, recent research reported a new point that PNI starts to include axon growth and possible nerve "invasion" to tumors as the component. More and more tumor-nerve crosstalk has been explored to explain the internal mechanism for tumor microenvironment (TME) of some types of tumors tends to observe nerve infiltration. As is well known, the interaction of tumor cells, peripheral blood vessels, extracellular matrix, other non-malignant cells, and signal molecules in TME plays a key role in the occurrence, development, and metastasis of cancer, as to the occurrence and development of PNI. We aim to summarize the current theories on the molecular mediators and pathogenesis of PNI, add the latest scientific research progress, and explore the use of single-cell spatial transcriptomics in this invasion way. A better understanding of PNI may help to understand tumor metastasis and recurrence and will be beneficial for improving staging strategies, new treatment methods, and even paradigm shifts in our treatment of patients.
PubMed: 36900158
DOI: 10.3390/cancers15051360