Background: Head and neck squamous cell carcinoma (HNSCC) exists within a microenvironment rich in immune cells. Macrophages are particularly abundant in and around tumor tissue, and have been implicated in the growth, malignancy, and persistence of HNSCC ( 1 ). However, current literature reports variable degrees of association between the density of tumor-associated macrophages (TAMs) and clinicopathologic markers of disease ( 2 , 3 ). These inconsistent findings may be a result of differences in approach to TAM detection. Authors have measured total TAMs in tumor tissue, while others have stained tumor samples for individual subtypes of TAMs, which include pro-inflammatory (M1-like) and immunosuppressive (M2-like). Our aim is to more clearly define the prognostic significance of the phenotypes of tumor-associated macrophages in HNSCC. Methods: We conducted a meta-analysis of the existing publications investigating the relationship between TAMs (total and M2-like subtype) and T stage, nodal involvement, vascular invasion, lymphatic invasion, and tumor differentiation ( Figure 1 ). A total of 12 studies were included. Forest plots and risk ratios were generated to report overall effect. Results: Higher density of both total and M2-like subtype of TAMs in the tumor microenvironment is associated with advanced T stage, increased rates of nodal positivity, presence of vascular invasion, and presence of lymphatic invasion ( p < 0.0001; Figures 2–9 ). There is no significant association between TAM density, either total or M2-like subtype, and tumor differentiation ( Figures 10 , 11 ). Conclusions: Increased density of TAMs, including those of the M2-like phenotype, correlate with poor clinicopathologic markers in HNSCC. Our findings warrant additional investigation into the subpopulations of TAMs, the mechanisms behind their recruitment and differentiation, and the associated influence of each phenotype on tumor growth and invasion. A greater understanding of TAM dynamics in HNSCC is critical for directing further research and employing TAM-targeted adjunct therapies.

Objective To determine the frequency at which patients with osteocutaneous free flap reconstruction of the head and neck develop long-term complications and identify predisposing perioperative factors. Study Design A prospectively maintained database of free flaps performed at a single institution over a 10-year period was queried. Setting Single tertiary care referral center. Subjects and Methods In total, 250 osseous or osteocutaneous free flaps (OCFFs) for mandibular or maxillary reconstruction were analyzed. Data were collected on demographics, preoperative therapy, resection location, adjuvant treatment, complications, and subsequent surgeries, and multivariate analysis was performed. Subgroup analysis based on perioperative factors was performed. Results The median follow-up time was 23 months. In 185 patients with at least 6 months of follow-up, 17.3% had at least 1 long-term complication, most commonly wound breakdown, fistula or plate extrusion (13.5%), osteoradionecrosis or nonunion (6.5%), and infected hardware (5.9%). Prior chemoradiotherapy and cancer diagnosis predisposed patients to long-term complications. At the 5-year follow-up, 21.7% of patients had experienced a long-term complication. Conclusions Long-term complications after OCFF occurred in 17% of patients. In this series, a preoperative history of chemoradiation and those undergoing maxillary reconstruction were at high risk for the development of long-term complications and thus warrant diligent follow-up. However, OCFFs can often enjoy long-term viability and survival, even in the case of perioperative complications and salvage surgery.

Objective To describe the natural history of bone segment union in head and neck free flap procedures and detail the association of poor segment union with postoperative complications. Study Design Case series with chart review. Setting Single tertiary care referral center. Subjects and Method Patients with mandibular or maxillary defects reconstructed with osseous or osteocutaneous free flaps were analyzed (n = 104). Postoperative computed tomography or positron emission tomography/computed tomography scans were reviewed for signs of osseointegration and nonunion. Postoperative wound complications were correlated with imaging findings. Result Thirty-seven percent of appositions had partial union on nonunion. Appositions between osteotomized free flap segments form complete unions at a higher rate than appositions with native bone (65% vs 53%, P = .0006). If an apposition shows a gap of ≥1 mm, the chances of failing to form a complete union are greatly increated (79% vs 8%, P = .0009). Radiographic nonunion was associated with an increased likelihood of postoperative wound complications (40% vs 19%, P = .025) and in most cases was present before development of complications. Conclusion Radiographic evidence of partial union or nonunion of free flap osseous segments greatly exceeds reported rates of clinically evident nonunion. Unions likely form between free flap appositions before unions to the native bone. If initial bone segments are >1-mm apart, the chance of progression to complete union is low. Incomplete osseointegration appears to be a marker for development of wound complications.

BACKGROUND The use of the pipeline embolization device (PED; Medtronic, Dublin, Ireland) in the posterior circulation has been limited and infrequently reported compared to other off-label utilizations. Posterior inferior cerebellar artery aneurysms (PICAA) constitute 1 of the least reported posterior circulation aneurysms treated with PED. No clinical studies have addressed the treatment of these aneurysms with flow diversion exclusively. OBJECTIVE To appraise the feasibility and the safety of PED in the treatment of PICAAs. METHODS Data on 12 consecutive patients, treated between 2011-2017 with PED for their PICAA, was retrospectively reviewed. To control confounding, we used multivariable logistic regression and propensity score conditioning. RESULTS Of 534 patients, 12 (9/12, 75% males) were identified and constituted our study population. The average aneurysm size was 8.47 mm (SD = 2.6, 3.7-14). Patients were followed-up for an average of 10.3 months (SD = 11 mo). Two of 12 (16.7%) had a prior history of subarachnoid hemorrhage. Eight of 12 (67%) of the aneurysms were saccular, 3/12 (25%) were dolichoectatic, and 1/12 (8%) was a small blister aneurysm. Eleven of 12 (92%) aneurysms were treated with 1 PED; 2/12 (16.7%) patients received combined pipeline assisted coiling. All patients had a complete occlusion, regression, and resolution of their aneurysm(s). PED deployment was neither complicated with any hemorrhagic or clinically significant thromboembolic events nor with device migration in any of our patients. Three of 12 (25%) patients had a benign intrastent stenosis. No mortality, among our 12 patients, was noted throughout the follow-up period. CONCLUSION PED, deployed by specialized experts, should be safe in treating PICAA. It can be contemplated as a novel alternative treatment of aneurysms located at the PICA-VA bifurcation or within the PICA.