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International Journal of Dermatology Jun 2022Squamous and basal cell carcinomas with perineural invasion are typically difficult to treat because of their propensity to metastasize, their aggressive nature, and the... (Review)
Review
Squamous and basal cell carcinomas with perineural invasion are typically difficult to treat because of their propensity to metastasize, their aggressive nature, and the concept of skip lesions. Perineural invasion is an under-recognized and underdiagnosed condition even though the literature points to its high rate of incidence in squamous cell carcinoma and a nonnegligible incidence rate in basal cell carcinoma. Perineural invasion has been linked to higher recurrence rates and poorer prognosis. This review has been written to aid clinicians in identifying and managing the condition as early as possible by describing the clinical and microscopic manifestations of perineural invasion.
Topics: Carcinoma, Basal Cell; Carcinoma, Squamous Cell; Humans; Neoplasm Invasiveness; Skin Neoplasms
PubMed: 34370865
DOI: 10.1111/ijd.15817 -
Anesthesiology Jun 2023The authors hypothesized that both perineural and systemic dexamethasone as adjuncts to bupivacaine increase the duration of an ulnar nerve block compared with... (Randomized Controlled Trial)
Randomized Controlled Trial
BACKGROUND
The authors hypothesized that both perineural and systemic dexamethasone as adjuncts to bupivacaine increase the duration of an ulnar nerve block compared with bupivacaine alone, and that systemic dexamethasone is noninferior to perineural dexamethasone.
METHODS
The authors performed bilateral ulnar nerve blocks with 3 ml bupivacaine 5 mg/ml in 16 healthy volunteers on two trial days. According to randomization, subjects received adjunct treatment with 1 ml dexamethasone 4 mg/ml + 1 ml of saline (perineural condition) in one arm and 2 ml saline in the other arm (systemic condition, through absorption and redistribution of the contralaterally administered perineural dexamethasone) on one trial day; and 2 ml saline in one arm (placebo condition) and 2 ml of lidocaine in the other arm (lidocaine condition) on the other trial day. The primary outcome was the duration of the sensory nerve block assessed by temperature discrimination.
RESULTS
Mean sensory block duration was 706 ± 94 min for the perineural condition, 677 ± 112 min for the systemic condition, and 640 ± 121 min for the placebo condition. The duration of the sensory nerve block was greater with perineural dexamethasone versus placebo (mean difference 66 min (95% CI, 23 to 108). Block duration was similar between systemic dexamethasone and placebo (mean difference 36 min; 95% CI, -30 to 103).
CONCLUSIONS
Perineural dexamethasone as an adjunct to bupivacaine in healthy volunteers resulted in a greater duration of an ulnar nerve block when compared with placebo. Systemic dexamethasone resulted in a similar duration as placebo.
Topics: Humans; Dexamethasone; Anesthetics, Local; Healthy Volunteers; Bupivacaine; Nerve Block; Lidocaine; Pain, Postoperative; Double-Blind Method
PubMed: 36912613
DOI: 10.1097/ALN.0000000000004557 -
Current Opinion in Anaesthesiology Oct 2023Moderate-to-severe pain is common and remains a significant problem. Compared with opioid analgesia alone, single-shot peripheral nerve blockade has been associated with... (Review)
Review
PURPOSE OF REVIEW
Moderate-to-severe pain is common and remains a significant problem. Compared with opioid analgesia alone, single-shot peripheral nerve blockade has been associated with improved pain relief and the potential of decreased side effects. Single-shot nerve blockade, however, is limited by its relatively short duration of action. In this review, we aim to summarize the evidence related to local anaesthetic adjuncts for peripheral nerve blockade.
RECENT FINDINGS
Dexamethasone and dexmedetomidine exhibit characteristics that most closely resemble the ideal local anaesthetic adjunct. In upper limb block, dexamethasone has been demonstrated to be superior to dexmedetomidine regardless of administration route for the duration of sensory and motor blockade as well as the duration of analgesia. No clinically significant differences between intravenous and perineural dexamethasone were found. Perineural and intravenous dexamethasone have the potential to prolong sensory blockade to a greater extent than motor blockade. The evidence indicates that the mechanism of action of perineural dexamethasone in upper limb block is systemic in nature. Unlike perineural dexmedetomidine, intravenous dexmedetomidine has not been shown to result in differences in the characteristics of regional blockade compared with local anaesthetic alone.
SUMMARY
Intravenous dexamethasone is the local anaesthetic adjunct of choice, increasing the duration of sensory and motor blockade as well as the duration of analgesia by 477, 289 and 478 min, respectively. In view of this, we recommend consideration of the intravenous administration of dexamethasone at a dose of 0.1-0.2 mg/kg for all patients undergoing surgery whatever the level of postoperative pain, mild, moderate or severe. Further research should focus on the potential synergism of action between intravenous dexamethasone and perineural dexmedetomidine.
Topics: Humans; Anesthetics, Local; Dexamethasone; Dexmedetomidine; Pain, Postoperative; Peripheral Nerves
PubMed: 37314172
DOI: 10.1097/ACO.0000000000001272 -
Eye (London, England) Apr 2023Perineural invasion (PNI) in cutaneous squamous cell carcinoma (SCC) of the periocular region is a prognostic marker of adverse tumour outcomes. PNI carries a... (Review)
Review
Perineural invasion (PNI) in cutaneous squamous cell carcinoma (SCC) of the periocular region is a prognostic marker of adverse tumour outcomes. PNI carries a well-established risk of tumour recurrence, regional metastasis and higher likelihood of mortality. This review will explore and stratify the risks conferred by histological PNI parameters. The radiological features of perineural spread (PNS) and the imaging sequences that delineate these findings will also be highlighted. Surgical excision with en face margin control is the preferred technique for achieving histological clearance. Adjuvant radiotherapy improves treatment outcomes in the setting of concomitant high-risk features. For locally advanced or metastatic cutaneous SCC, immunotherapy represents a novel treatment alternative. This review will provide an algorithm for the diagnosis and management of periocular SCC with PNI and PNS.
Topics: Humans; Carcinoma, Squamous Cell; Skin Neoplasms; Neoplasm Recurrence, Local; Treatment Outcome; Radiotherapy, Adjuvant; Neoplasm Invasiveness; Prognosis; Retrospective Studies
PubMed: 36400852
DOI: 10.1038/s41433-022-02306-w -
American Journal of Clinical Dermatology Sep 2021Perineural invasion is an infiltrative process of peripheral nerves by the primary neoplasm within the immediate vicinity. Aggressive forms of keratinocyte carcinomas,... (Review)
Review
Perineural invasion is an infiltrative process of peripheral nerves by the primary neoplasm within the immediate vicinity. Aggressive forms of keratinocyte carcinomas, such as basal cell and squamous cell carcinomas, may feature perineural invasion, which is often associated with tumor recurrence and poorer prognosis. Diagnosis requires a high clinical suspicion. Imaging and histopathology are used to assess for extent of disease while surgical excision with complete circumferential peripheral and margin assessment is the treatment goal. However, there is still significant uncertainty about adjuvant chemotherapy and definitive management guidelines. Here, we summarize the current understanding of this complex pathogenic process, the clinical presentation, and the significance of perineural inflammation. We also discuss the recommendations about staging, prognosis, adjuvant radiotherapy, and general guidelines for managing keratinocyte carcinomas with perineural invasion. A better understanding of perineural invasion is essential to improve diagnosis, tailor interventions, and mitigate patient morbidity and mortality.
Topics: Carcinoma, Squamous Cell; Humans; Keratinocytes; Neoplasm Invasiveness; Neoplasm Recurrence, Local; Peripheral Nervous System Neoplasms
PubMed: 34105084
DOI: 10.1007/s40257-021-00615-6 -
Journal of Neurological Surgery. Part... Apr 2016Perineural invasion (PNI) is the neoplastic invasion of nerves. PNI is widely recognized as an important adverse pathological feature of many malignancies, including... (Review)
Review
Perineural invasion (PNI) is the neoplastic invasion of nerves. PNI is widely recognized as an important adverse pathological feature of many malignancies, including pancreatic, prostate, and head and neck cancers and is associated with a poor prognosis. Despite widespread acknowledgment of the clinical significance of PNI, the mechanisms underlying its pathogenesis remain largely unknown. Recent theories of PNI pathogenesis have placed a significant emphasis on the active role of the nerve microenvironment, with PNI resulting from well-orchestrated reciprocal interactions between cancer and host. Elucidating the mechanisms involved in PNI may translate into targeted therapies for this ominous process.
PubMed: 27123385
DOI: 10.1055/s-0036-1571835 -
Clinical Radiology Feb 2017Palatal tumours are relatively rare and of variable aetiology, rendering radiological evaluation a daunting process for many. A systematic approach to the imaging of a... (Review)
Review
Palatal tumours are relatively rare and of variable aetiology, rendering radiological evaluation a daunting process for many. A systematic approach to the imaging of a palatal lump is therefore essential. The hard and soft palates are oral cavity and oropharyngeal structures, respectively. They have different tissue compositions, and therefore, lesions occur with different frequencies at each site. The hard palate has the highest concentration of minor salivary glands in the upper aerodigestive tract and most tumours here are salivary in origin, whereas most tumours at the soft palate are epithelial in origin, i.e., squamous cell carcinomas, in line with other oropharyngeal subsites. The most common malignant tumours of the palate, after squamous cell carcinoma, are minor salivary gland tumours, predominantly adenoid cystic and mucoepidermoid carcinomas. These tumours have a propensity to spread perineurally; understanding the anatomy and imaging features of perineural spread is vital, as it can have significant implications for patient management and tumour resectability. When confronted with a palatal lump, it is important to consider the following: its location on the hard or soft palate; whether it is mucosal or submucosal; the frequently occurring lesions at that site; the most suitable imaging techniques (ultrasound, computed tomography, magnetic resonance imaging); whether there are typical imaging features for any of the common lesions; and whether there are aggressive features, such as bone erosion or perineural spread. This approach allows the radiologist to narrow the differential diagnosis and assist the clinicians with planning treatment.
Topics: Diagnosis, Differential; Humans; Image Enhancement; Magnetic Resonance Imaging; Palatal Neoplasms; Tomography, X-Ray Computed; Ultrasonography
PubMed: 27986264
DOI: 10.1016/j.crad.2016.10.007 -
Frontiers in Genetics 2022Carcinomas of the oral cavity and oropharynx belong among the ten most common malignancies in the human population. The prognosis of head and neck squamous cell... (Review)
Review
Carcinomas of the oral cavity and oropharynx belong among the ten most common malignancies in the human population. The prognosis of head and neck squamous cell carcinoma (HNSCC) is determined by the degree of invasiveness of the primary tumor and by the extent of metastatic spread into regional and distant lymph nodes. Moreover, the level of the perineural invasion itself associates with tumor localization, invasion's extent, and the presence of nodal metastases. Here, we summarize the current knowledge about different aspects of epigenetic changes, which can be associated with HNSCC while focusing on perineural invasion (PNI). We review epigenetic modifications of the genes involved in the PNI process in HNSCC from the omics perspective and specific epigenetic modifications in OSCC or other neurotropic cancers associated with perineural invasion. Moreover, we summarize DNA methylation status of tumor-suppressor genes, methylation and demethylation enzymes and histone post-translational modifications associated with PNI. The influence of other epigenetic factors on the HNSCC incidence and perineural invasion such as tobacco, alcohol and oral microbiome is overviewed and HPV infection is discussed as an epigenetic factor associated with OSCC and related perineural invasion. Understanding epigenetic regulations of axon growth that lead to tumorous spread or uncovering the molecular control of axon interaction with cancer tissue can help to discover new therapeutic targets for these tumors.
PubMed: 35571032
DOI: 10.3389/fgene.2022.848557 -
Advances in Anatomic Pathology Mar 2017Perineural invasion (PNI) is characterized as tumoral or nontumoral cells invading in or around the nerves. The neural invasion is considered as a histopathologic... (Review)
Review
Perineural invasion (PNI) is characterized as tumoral or nontumoral cells invading in or around the nerves. The neural invasion is considered as a histopathologic characteristic for malignancy and is considered a mechanism for its spread. Both of these patterns usually portend a poor prognosis and very often are markers to prompt additional treatment. There are also some nonmalignancies representing PNI, including benign neoplasms, mimicking lesions, and disorders, such as chronic pancreatitis and endometriosis. The previously recommended terms are PNI, spread, or infiltration. To distinguish PNI in malignancies from that in nonmalignancies, we propose the term "perineural pseudoinvasion" to convey their nonmalignant behavior. Despite the low prevalence, awareness of this benign pseudoinvasion is necessary to avoid aggressive treatment and its misdiagnosis with malignancies. We conducted a systematic search in PubMed and Scopus databases up to December 2015 to find articles reporting PNI in nonmalignancies. After screening, 63 articles were identified as relevant. There were also 2 review articles discussing PNI in nonmalignancies. We aim to present an overview of the perineural pseudoinvasion and to discuss the previously published review articles.
Topics: Biomarkers, Tumor; Humans; Lymphatic Metastasis; Myofibroma; Neoplasm Invasiveness; Neoplasms; Prognosis
PubMed: 28181952
DOI: 10.1097/PAP.0000000000000143 -
The British Journal of Radiology Aug 2022Acetabular paralabral cysts are common and are almost always associated with labral tears. Uncommonly, they extend into the periacetabular soft tissues or may propagate...
OBJECTIVE
Acetabular paralabral cysts are common and are almost always associated with labral tears. Uncommonly, they extend into the periacetabular soft tissues or may propagate along peripheral nerves causing pain and hip dysfunction. The aim was to evaluate the clinical and MRI presentations of such cases including perineural propagation.
METHODS
Retrospective cross-sectional study with a search of electronic health records for cases of acetabular paralabral cysts demonstrating perineural propagation was performed. Clinical and MR imaging features were tabulated after re-review by experienced musculoskeletal radiologists, and available outcomes were recorded. Descriptive statistics were performed.
RESULTS
14 cases were recorded. The mean age was 56.9 years (range = 30-79 years) and female:male ratio was 1:2.6. The commonest presenting complaint was hip pain (10/14, 71.4%). Other complaints included groin pain, perineal pain and hip dysfunction. No symptoms were attributed to the acetabular paralabral cyst in 3/14 patients (21.4%). None had foot drop. The cysts were multilocular in all cases and were homogenously T2 hyperintense in 13/14 (92.9%). Labral tears were identified in 11/14 cases (78.6%). The sciatic nerve was most commonly involved in 5/14 cases (35.7%) with the obturator, medial femoral cutaneous nerve, femoral nerve, superior and inferior gluteal nerves also affected.No intervention was undertaken in 9/14 cases (64.3%). 5/14 (35.7%) underwent image guided aspiration and corticosteroid injection. 4/5 such patients reported reduced pain following the procedure.
CONCLUSION
Paralabral cysts demonstrating perineural propagation are uncommon and exhibit varied presentations. Most patients who underwent image-guided or surgical interventions reported an improvement in symptoms.
ADVANCES IN KNOWLEDGE.
This is the first description of a series of patients with acetabular paralabral cysts demonstrating perineural propagation in the literature. A comprehensive description of their clinical and imaging characteristics and interventions/outcomes where relevant is provided.
Topics: Acetabulum; Adult; Aged; Arthralgia; Arthroscopy; Cross-Sectional Studies; Cysts; Female; Humans; Magnetic Resonance Imaging; Male; Middle Aged; Retrospective Studies
PubMed: 35762342
DOI: 10.1259/bjr.20211306