Search

Pathogen emergence (PE) is a complex phenomenon with major public health implications. Over the past decades, numerous underlying mechanisms facilitating the emergence of pathogenic bacteria have been elucidated. In this review, we highlight the diverse molecular and environmental drivers associated with PE, with an emphasis on the interplay of canonical gene transfer mechanisms and the increasingly appreciated role of genetic variations, providing a more coherent picture of this process. Given the interactive and multifactorial nature of PE, we contend that the development of approaches that embrace the integration of these factors is indispensable in order to truly comprehend this complex phenomenon and develop strategies to mitigate this threat.

Due to the risk of occult cervical metastasis, elective neck dissection (END) is recommended in the management of patients with early oral cavity squamous cell carcinoma (OSCC) and a clinically node-negative (cN0) neck. This paper presents a systematic review and meta-analysis of studies that recorded isolated regional recurrence (RR) in the pathologically node-negative neck dissection (pN0) neck following END in order to quantify the failure rate. Pubmed and Ovid databases were systematically searched for relevant articles published between January 2009 and January 2019. Studies reporting RR following END in patients with OSCC who had no pathological evidence of lymph node metastasis were eligible for inclusion in this meta-analysis. In addition, a selection of large head and neck units were invited to submit unpublished data. Search criteria produced a list of 5448 papers, of which 18 studies met the inclusion criteria. Three institutions contributed unpublished data. This included a total of 4824 patients with median follow-up of 34 months (2.8 years). Eight datasets included patients staged T1-T4 with RR 17.3% (469/2711), 13 datasets included patients staged T1-T2 with RR 7.5% (158/2113). Overall across all 21 studies, isolated neck recurrence was identified in 627 cases giving a RR of 13.0% (627/4824) on meta-analysis. Understanding the therapeutic effectiveness of END provides context for evaluation of clinical management of the cN0 in these patients. A pathologically negative neck does not guarantee against future recurrence.

The evaluation of speech outcomes after resection and reconstruction of the oral tongue remains largely unsystematic. A cross-sectional study was performed to analyse the speech outcomes of patients who underwent curative treatment with appropriate reconstruction. Sixty-nine patients were assessed for speech intelligibility and phonetics using a validated speech intelligibility assessment tool in the local language. Volume defects were classified as class I (less than one third), II (one third to half), III (half to two-thirds), or IV (two-thirds to total glossectomy). Defect location was defined as lateral, tip, or sulcus. The χ2 test and Kruskal-Wallis test were used to test volume and location as predictors. Twenty-six patients had class I defects, 29 had class II defects, seven had class III defects, and seven had class IV defects. Twenty-two patients (31.9%) received adjuvant radiotherapy. Mean vowel, consonant, word, and paragraph intelligibility were 99.27%, 86.86%, 85.52%, and 88.72%, respectively. The incremental volume of the glossectomy defect was significantly correlated with speech intelligibility scores and phonatory alterations. In classes II and III, tip resection significantly affected interdental sounds. All patients in class III had affected alveolar and alveo-palatal sounds. The results positively corroborated the volume and location of the glossectomy defect to a classification system.

The aim of this study was to identify patterns of tumor growth as revealed on magnetic resonance imaging (MRI) and to evaluate the correlation of these patterns with histopathologic features and rates of recurrence, disease-free survival (DFS), and overall survival (OS).In a retrospective analysis of patients with tongue carcinoma, tumor advancing margins, patterns of tumor enhancement, and enhancement beyond tumor margins were studied on MRI. Histopathologic findings included differentiation, margin status, perineural invasion (PNI), and lymphovascular invasion (LVI). MRI and histopathologic features were correlated with outcomes.Ill-defined tumor margins and enhancement beyond tumor margins were associated with recurrences (P ≤ .001) regardless of perineural invasion or LVI. DFS and OS were adversely affected by ill-defined tumor margins (P ≤ .010). DFS was also affected by enhancement beyond the tumor margins (P.001). A heterogeneous pattern of enhancement showed a trend toward a decrease in DFS and OS (P = .088 and .092, respectively). Advancing tumor margins on MRI were independent predictors of overall survival. MRI characteristics exhibited significant associations with histopathologic margins, PNI, and LVI.Ill-defined advancing tumor margins, a heterogeneous pattern of enhancement, and enhancement beyond the tumor margins on MRI adversely affect outcomes and prognosis in tongue carcinoma.

Objectives To study the determinants of locoregional control (LRC) on stage I/II oral squamous cell carcinoma (OSCC) classified by AJCC 8th edition. Methods Retrospective analysis from 296 patients of pT1-2N0 oral OSCC treated with surgery (wide local excision and selective neck dissection). Those receiving adjuvant therapy were excluded. Multivariate analysis was performed for impact of adverse pathological features (APFs) on LRC. Results In stage I, LRC was impacted by perineural invasion (PNI) (HR 7.72, p = 0.010, 95% CI 1.64–36.26) and moderate/poor differentiation (MD/PD) (HR 3.04, p = 0.049, 95% CI 0.99–9.25). In stage II, LRC was impacted by depth of invasion (DOI) (HR 1.59, p = 0.014, 95% CI 1.099–2.32), PNI (HR = 2.86, p = 0.005, 95% CI 1.36–5.98). Combined MD/PD and PNI were associated with worse LRC than either feature individually (HR = 4.12, p Conclusion PNI and differentiation accurately predict LRC in AJCC 8th edition classified stage I/II OSCC. PNI was a stronger predictor of locoregional failure than DOI in stage II disease. By incorporating these parameters, we can improve precision in staging of early OSCC and identify potential candidates for treatment escalation to improve outcomes.

According to the eighth edition of the AJCC Cancer Staging Manual (AJCC8), a depth of invasion (DOI)10mm is classified as pT3, representing a locally advanced tumour requiring postoperative radiotherapy (PORT). When node-negative, however, evidence regarding whether PORT improves loco-regional control or survival is unclear. To clarify this, two cohorts of patients were studied: (1) patients classified as pT3N0 by the seventh edition of the AJCC manual (AJCC7), with DOI10mm and a tumour diameter4cm (17 patients who received PORT), and (2) patients classified as pT1N0 and pT2N0 by AJCC7, with DOI10mm and a tumour diameter4cm (55 patients who did not receive PORT). Loco-regional control and survival were analysed. PORT was found not to impact overall survival or disease-free survival. It was also found not to impact local, regional, or distant recurrence. Although the two subsets of patients considered here (DOI10mm with tumour diameter below or above 4cm) were previously distinct, they are both considered pT3 in AJCC8. Data from this study indicate that the routine administration of PORT to patients with a DOI10mm may not be warranted in the absence of other risk features such as nodal disease or close margins.

Objectives The purpose of this paper is to report the technique and outcomes of the use of gastro-omental free flap reconstruction in glossectomy defects. Materials and Methods This is a prospective case series of 9 patients of tongue squamous cell carcinoma, who underwent either subtotal or partial glossectomy and reconstruction with gastro–omental free flap. The flap anatomy, surgical technique and the outcomes including the swallowing and speech are presented. Results Five patients underwent partial glossectomy and 4 had sub-total glossectomy. The median age was 43 years; and the median follow up was 11.4 months. Laparoscopic harvest was done in 8 patients. There was one flap loss. Seven patients underwent postoperative radiotherapy. Functional evaluation was done in 5 patients who were disease free. Four could tolerate soft diet orally, one patient was on liquid to pureed diet. Speech was intelligible in 4. None of the patients had any complications related to laparotomy or laparoscopy. Conclusion Gastro-omental flap provided a secretory mucosal surface and was beneficial in the saliva depleted patients post radiotherapy. The laparoscopic harvest of this flap has minimized donor site morbidity. One patient had a flap loss. Two patients reported superficial ulcerations on the surface, one of them had to undergo surgical debulking to correct it while the other healed with conservative measures. Speech and swallowing outcomes of the reconstructed tongue was good, especially in patients with partial glossectomy. The reconstructed gastric mucosal flaps tolerated the adjuvant radiation well.

The use of postoperative radiotherapy (PORT) in early stage oral cancer with adverse pathologic features (APFs) is controversial. Prognostically relevant APFs reviewed were perineural invasion, lymphovascular invasion, depth of invasion, worst pattern of invasion, and margin status. The current literature remains divided with regard to the benefit of treatment escalation in these patients; although these patients are at high risk for recurrence, the morbidity of PORT needs to be balanced against the likely benefit in disease control. A wide heterogeneity in the literature exists, likely as a result of differences in treatment protocols. We performed a literature review of the role of PORT in early-stage oral cancer with APFs. Based on the current evidence, the decision to administer adjuvant therapy needs to be made on an individual basis; patients with >1 APF are likely to benefit from PORT, and the use of risk-scoring systems may help in decision making.

In developing countries, oral squamous cell carcinoma (OSCC) is predominantly a cancer affecting older males who smoke tobacco. In countries with effective public health strategies, smoking rates are declining rapidly. It is not clear if patients who develop OSCC without these traditional risk factors represent a clinically distinct cohort with different prognosis. A recent analysis found that elderly non-smoking females with OSCC had significantly worse prognosis, concluding that this was a distinct patient population with poorer survival. The primary aim of this study was to determine the effect of gender and age on prognosis in OSCC, and the interaction between these two variables.Multinational multi-institutional data were collected from six sites. The primary outcome of interest was disease specific survival (DSS). Time to local, regional, and distant recurrence were investigated as secondary outcomes.3379 patients with OSCC were included. Males had significantly worse DSS compared to females (HR 1.24, 95% CI 1.08-1.43, p = 0.003). Females70 years of age had significantly better DSS compared to females ≥70 years of age (HR 0.69, 95% CI 0.51-0.94, p 0.001) but elderly females had similar DSS to males, regardless of age. When age was divided into three groups, the middle-aged group (45-69 years) had a significantly better DSS compared to elderly patients (HR 0.87, 95%CI 0.78-0.96, p 0.001), however younger patients had similar DSS to elderly patients. When the effect of age (young v middle v elderly) was compared in each gender, young and middle-aged females had the most favourable DSS (log-rank p 0.001). Middle-aged females who smoked had a 10% survival advantage compared to middle-aged males that smoked at five years.Age, gender, tumour subsite, and smoking status are important drivers of survival in OSCC. However, gender appears to be the most important predictor with young and middle-aged females having the most favourable prognosis.

Over the last few decades evidence has accumulated for increasing incidence of oral cavity squamous cell carcinoma (OSCC) in a younger cohort. Prior studies examining the effect of age at diagnosis on prognosis have produced conflicting data.A multi-institutional cohort study was performed across 6 different sites in Australia, Canada, India and Singapore. Disease-free (DFS), overall (OS) and disease-specific (DSS) survival were analysed. The association of the number of adverse features with survival outcomes was investigated.From 3179 patients, age was a significant predictor of OS with patients older than 45 years having a 66% increased risk of death (HR 1.66, 95%CI 1.33 - 2.07, p 0.001). The number of adverse features was a significant predictor of OS with 3 or more adverse features having a 199% increased risk (HR 2.99, 95%CI 2.61-3.43. p 0.001). The estimate effect was greater in patients ≤ 45 years (HR 3.49 vs HR 2.81). Age was not a significant predictor of DSS with similar rates of death from OSCC in multivariable models. The number of adverse features was a significant predictor of DFS with ≥ 3 adverse features having a 140% increased risk of death. The number of adverse features was a significant predictor of DSS with ≥ 3 adverse features having a 230% increased risk of disease specific death.Age is not an independent predictor of disease specific mortality in OSCC. Differences in outcomes are due to the confounding effect of adverse clinicopathological features and the ability to tolerate surgery and adjuvant therapy.

Recently, there have been significant developments in our understanding of salivary gland pathology, and new entities, such as mammary analogue secretory carcinoma, have been described. Attempts are being made to identify effective therapeutic agents for salivary duct carcinomas by using molecular diagnostic techniques. Concepts such as high-grade transformation have been described, which not only influence macroscopic and microscopic evaluation of a specimen but, given the high incidence of metastases and morbidity, also carry significant treatment implications. Specific chromosomal translocations, which can be detected by fluorescent in situ hybridization, can augment diagnostic accuracy and carry prognostic implications. The landscape of benign salivary gland lesions is changing with better understanding of chronic sclerosing sialadenitis related to IgG4. This multiorgan inflammatory condition may primarily present as a salivary gland lesion and clinically and radiologically mimic a salivary gland malignancy. Histology and immunohistochemistry play a critical role in its accurate diagnosis. The purpose of this article is to review these changes, with an emphasis on their effect on patient management. Given their diagnostic, prognostic, and therapeutic implications, it is critical that surgeons, oncologists, pathologists, and those involved in caring for patients with salivary gland tumors are aware of these changes while considering management options.

Purpose Antithrombotic agents have been used in microvascular surgeries. Low Molecular Weight Dextran (Dextran 40) though used, is not without complications. Materials and methods Retrospective analysis of 172 consecutive flaps. A comparison was done between two groups of patients (86 flaps each) with and without the use of Dextran 40, in terms of safety and efficacy. Results 168 patients underwent 172 microvascular free flaps for reconstruction of head and neck oncologic defects during the study period. The mean age was 55.6 years (range 18–85 years). The groups were comparable in terms of pulmonary, cardiac co-morbidity and history of any prior radiotherapy. Of the 172 flaps, 26 flaps required re-exploration. 21 flaps could be salvaged. There were five total flap failures. The free flap survival rate was 95.9%. The five free flap failures included one radial forearm free flap, two fibular free flaps and two antero-lateral thigh flaps. There were six partial flap losses. Fourteen flaps had venous thrombosis. Four flaps had arterial thrombosis, of which one each in both the groups could not be salvaged. There were seven patients with postoperative hematoma requiring surgical intervention. All of these free flaps survived after hematoma evacuation. None of the patients developed ARDS or required prolonged ventilator support. No patient had dextran related anaphylactoid reactions. 38 patients (43.7%) in Group A had post-operative atelectasis and 21 (25.6%) patients in Group B had this complication. This difference was statistically significant ( p = 0.01). Six patients in Group A developed post-operative pneumonia while five patients in Group B developed this complication. This difference was statistically not significant ( p = 0.93). The mean duration of intensive care unit stay was 6.8 and 6.9 h respectively for the Groups A and B. Similarly, the mean hospital stay was 14.1 and 13.4 days respectively for the groups A and B. These differences were also not significantly different among the groups. Conclusions Though Dextran 40 did not result in any significant adverse local or systemic complications, it is not useful as a post operative antithrombotic agent in head and neck oncologic defect reconstruction with free tissue transfer.