Occult Nodal Metastases in Individuals with Clinically Node-Negative Salivary Gland Malignancies

OBJECTIVES

Salivary gland malignancies comprise a heterogeneous group of pathologies, for which treatment of the clinically negative neck may vary depending on numerous factors. Herein we present data on occult nodal metastases (ONM) as well as survival and recurrence from a large series of cN0 salivary gland malignancies.

METHODS

Retrospective chart review was conducted on 532 patients, with 389 patients with major salivary gland cancers and 143 patients with minor salivary gland cancers. Demographic and treatment data were included and rates of ONM, overall survival, local recurrence, regional recurrence, and distant recurrence were analyzed.

RESULTS

We found that the overall rate of ONM for parotid was 27% (63/235), for submandibular/sublingual was 35% (18/52), and for minor was 15% (4/26). Analysis of ONM rate at each nodal level was also performed, finding higher rates of level IV and V ONM than prior studies. Submandibular/sublingual and minor salivary gland malignancies showed a predominance of ONMs at levels I-III. Our survival and recurrence rates were similar to those found in previous studies.

CONCLUSION

Our data also demonstrate a predominance of ONM in levels I-III for submandibular/sublingual and minor salivary gland cancers, suggesting elective dissection in these levels.

LEVEL OF EVIDENCE

4 Laryngoscope, 134:1705-1715, 2024.

Clinical Versus Pathologic Laryngeal Cancer Staging and the Impact of Stage Change on Outcomes

OBJECTIVES/HYPOTHESIS

Evaluate the impact and accuracy of clinical laryngeal cancer staging.

STUDY DESIGN

Retrospective cohort study.

METHODS

Two hundred sixty-five consecutive patients with laryngeal squamous cell carcinoma who underwent total laryngectomy from 2001 to 2017 were studied. Clinical versus pathologic tumor (T) and nodal (N) categories were compared. Logistic regression and Cox proportional hazards analyzed the association of stage change with perioperative factors and outcomes.

RESULTS

Forty-seven patients (17.7%, accuracy = 0.969 ± 0.010 [standard error]) changed between T1-2 and T3-4. Sixty-four patients (24.1%, accuracy = 0.866 ± 0.020) had inaccurate N category. Salvage patients were less likely to have stage change (downstage: odds ratio [OR] = 0.20, 95% confidence interval [CI]: 0.08-0.50, P < .001; upstage: OR = 0.41, 95% CI: 0.23-0.74, P = .003), but more likely to have inaccurate nodal category (39.8% vs. 11.7%, P < .001). Patients with stage change tended to have greater odds of positive/close margins (upstage: OR = 1.78, 95% CI: 0.91-3.5, P = .092) and chemotherapy (downstage: OR = 2.21, 95% CI: 0.80-6.14, P = .128; upstage: OR = 1.87, 95% CI: 0.85-4.11, P = .119). Stage change was associated with recurrence (P = .047) with downstaged patients less likely to recur (hazard ratio = 0.26, 95% CI: 0.08-0.82, P = .021). Stage change was not associated with positron emission tomography scan, subsite, time to surgery, or mortality.

CONCLUSIONS

A third of laryngeal cancer patients were downstaged or upstaged after laryngectomy with 18% and 24% of clinical T and N categories inaccurate, respectively. Stage change was less common for salvage patients and associated with risk of recurrence.

LEVEL OF EVIDENCE

3 Laryngoscope, 131:559-565, 2021.

Antibiotic resistance is lower in Staphylococcus aureus isolated from antibiotic-free raw meat as compared to conventional raw meat

The frequent use of antibiotics contributes to antibiotic resistance in bacteria, resulting in an increase in infections that are difficult to treat. Livestock are commonly administered antibiotics in their feed, but there is current interest in raising animals that are only administered antibiotics during active infections. Staphylococcus aureus (SA) is a common pathogen of both humans and livestock raised for human consumption. SA has achieved high levels of antibiotic resistance, but the origins and locations of resistance selection are poorly understood. We determined the prevalence of SA and MRSA in conventional and antibiotic-free (AF) meat products, and also measured rates of antibiotic resistance in these isolates. We isolated SA from raw conventional turkey, chicken, beef, and pork samples and also from AF chicken and turkey samples. We found that SA contamination was common, with an overall prevalence of 22.6% (range of 2.8-30.8%) in conventional meats and 13.0% (range of 12.5-13.2%) in AF poultry meats. MRSA was isolated from 15.7% of conventional raw meats (range of 2.8-20.4%) but not from AF-free meats. The degree of antibiotic resistance in conventional poultry products was significantly higher vs AF poultry products for a number of different antibiotics, and while multi-drug resistant strains were relatively common in conventional meats none were detected in AF meats. The use of antibiotics in livestock contributes to high levels of antibiotic resistance in SA found in meat products. Our results support the use of AF conditions for livestock in order to prevent antibiotic resistance development in SA.

Isolation and Host Range of Bacteriophage with Lytic Activity against Methicillin-Resistant Staphylococcus aureus and Potential Use as a Fomite Decontaminant

Staphylococcus aureus (SA) is a commensal bacterium and opportunistic pathogen commonly associated with humans and is capable of causing serious disease and death including sepsis, pneumonia, and meningitis. Methicillin-resistant SA (MRSA) isolates are typically resistant to many available antibiotics with the common exception of vancomycin. The presence of vancomycin resistance in some SA isolates combined with the current heavy use of vancomycin to treat MRSA infections indicates that MRSA may achieve broad resistance to vancomycin in the near future. New MRSA treatments are clearly needed. Bacteriophages (phages) are viruses that infect bacteria, commonly resulting in death of the host bacterial cell. Phage therapy entails the use of phage to treat or prevent bacterial infections. In this study, 12 phages were isolated that can replicate in human SA and/or MRSA isolates as a potential way to control these infections. 5 phage were discovered through mitomycin C induction of prophage and 7 others as extracellular viruses. Primary SA strains were also isolated from environmental sources to be used as tools for phage discovery and isolation as well as to examine the target cell host range of the phage isolates by spot testing. Primary isolates were tested for susceptibility to oxacillin in order to determine which were MRSA. Experiments were performed to assess the host range and killing potential of newly discovered phage, and significant reductions in bacterial load were detected. We explored the utility of some phage to decontaminate fomites (glass and cloth) and found a significant reduction in colony forming units of MRSA following phage treatment, including tests of a phage cocktail against a cocktail of MRSA isolates. Our findings suggest that phage treatment can be used as an effective tool to decontaminate human MRSA from both hard surfaces and fabrics.