Pathologic Factors Associated with Low Risk of Lymph Node Metastasis in Nonmucinous Adenocarcinoma of the Appendix.

BACKGROUND: Right hemicolectomy (RHC) for nodal staging is recommended for nonmucinous adenocarcinoma of the appendix (NMACA), but it is unclear whether a subgroup of patients at low risk for lymph node (LN) metastasis exists who may be managed with a less extensive resection. PATIENTS AND METHODS: Patients with NMACA without distant metastases who underwent margin negative resection via either RHC or appendectomy/partial colectomy (A/PC) were evaluated from the National Cancer Database (2004-2016). Patients at low risk for LN metastasis were identified. Multivariable survival analysis was performed, and 5-year overall survival (OS) was estimated. RESULTS: Of the 2487 patients included, 652 [26.2%; 95% confidence interval (CI) 24.5-28.0%] had LN metastases. T4 T stage [odds ratio (OR) 4.2, p = 0.032], poorly/undifferentiated histology (OR 2.2, p = 0.004), and lymphovascular invasion (LVI) (OR 4.4, p < 0.001) were associated with LN positivity. One hundred and thirteen patients (4.5%) had tumors at low risk for LN metastasis (T1 T stage, well/moderately differentiated tumors without LVI), and the rate of LN metastasis for this group was 1.8% (95% CI 0.5-6.2%). Conversely, the LN metastasis rate among the 2374 non-low-risk patients was 27.4% (95% CI 25.6-29.2%). Performance of A/PC instead of RHC was associated with a survival disadvantage among all patients (hazards ratio 1.5, p = 0.049), but among the low-risk cohort, 5-year OS did not differ based on resection type (88.3% A/PC versus 92.7% RHC, p = 0.305). CONCLUSIONS: Although relatively uncommon, early, pathologically favorable NMACA is associated with a very low risk of LN metastasis. These select patients may be managed with a less extensive resection without compromising oncologic outcomes.

Trends in infectious complications after partial colectomy for colon cancer over a decade: A national cohort study.

BACKGROUND: The American College of Surgeons National Surgical Quality Improvement Program helps participating hospitals track and report surgical complications with the goal of improving patient care. We sought to determine whether postoperative infectious complications after elective colectomy for malignancy improved among participating centers over time. METHODS: Patients with colon malignancies who underwent elective partial colectomy with primary anastomosis (categorized as low or non-low) were identified from the American College of Surgeons National Surgical Quality Improvement Program database (2011-2019). Thirty-day postoperative infectious complications analyzed by year included superficial, deep, and organ space surgical site infections, urinary tract infection, pneumonia, and sepsis. Trends in patient and treatment characteristics were investigated using log-linear regression along with their association with infectious outcomes. RESULTS: Of the 78,827 patients identified, 51% were female, and the median age was 68. The majority (84%) underwent partial colectomy without a low anastomosis. There was a decrease in all infectious complications except for organ space infections which increased 35% overall from 2.0 to 2.7% (P = .037), driven by patients without a low anastomosis (1.9%-2.7%, P = .01). There was no change in most patient factors associated with organ space infections, except for a notable increase in American Society of Anesthesiologists class III and IV-V patients over time, both associated with organ space infections (P < .001; P = .002). CONCLUSION: Infectious complications have decreased significantly overall after colectomy for colon cancer, whereas there has been an increase in organ space infection rates specifically. Although changing patient characteristics may contribute to this observed trend, further study is needed to better understand its etiology to help mitigate this complication.

Interlaminar stabilization for spinal stenosis in the Medicare population.

BACKGROUND CONTEXT: The number of complex fusions performed on Medicare beneficiaries, defined as ≥age 65, with lumbar spinal stenosis with or without spondylolisthesis has been increasing. Typically, these procedures are longer, more invasive and pose a greater risk for complications. Interlaminar stabilization (ILS) serves as an intermediary between decompression alone and decompression with fusion. PURPOSE: The purpose of this study was to prospectively examine the efficacy of ILS in patients ≥age 65 through comparison to fusion in the same age group and ILS in younger patients. STUDY DESIGN/SETTING: A prospective, multicentered, randomized controlled trial comparing decompression with ILS to decompression with posterolateral fusion with bilateral pedicle screw instrumentation. PATIENT SAMPLE: Patients from 21 sites in the United States underwent surgery for moderate stenosis with up to a grade 1 degenerative spondylolisthesis and failure of conservative treatment with low back pain at 1 or 2 contiguous levels from L1-L5. Preoperatively, patient-reported assessment had to meet the criteria of significant pain and disability (Visual Analog Scale [VAS back pain] ≥50 mm on a 100 mm scale; Oswestry Disability Index [ODI] of ≥20/50). OUTCOME MEASURES: The primary outcome was overall Composite Clinical Success (CCS) as determined by ODI scores, incidence of postoperative epidural injections and/or reoperations, incidence of device-related complications, and persistent or progressive neurological deficit. Secondary outcomes included patient satisfaction as measured by VAS for back and worse leg pain and Zurich Claudication Questionnaire scores. Narcotic usage data and radiographic assessment of changes in postoperative posterior disc height and foraminal height were also evaluated. METHODS: At 1- or 2-levels, 84 patients ≥age 65 underwent decompression with ILS, 57 patients ≥age 65 underwent decompression with fusion, and 131 patients

Limb Salvage and Reconstruction Options in Osteosarcoma.

Advances in chemotherapy, sophisticated imaging, and surgical techniques over the last few decades have allowed limb-salvage surgery (LSS) to become the preferred surgical treatment for bone sarcomas of the extremities. The goal of LLS is to maximize limb functionality to allow for the maintenance of quality of life without compromising overall survival and tumor local recurrence rates. Today, limb-salvage procedures are performed on 80-95% of patients with extremity osteosarcoma, and the 5-year survival rate in extremity osteosarcoma patients is now 60-75%.This chapter will focus on LSS for extremity osteosarcoma. Common types of surgical reconstruction techniques including endoprostheses, intercalary or osteoarticular allografts, vascularized fibular autografts, and allograft prosthetic composites (APC), and their complications such as infection, local recurrence, graft fracture, implant failure, and nonunion will be discussed in detail. Anatomic locations of lesions discussed include the proximal femur, distal femur, proximal tibia, distal tibia, proximal humerus, distal humerus, and forearm bones.

Spinal Stenosis in the Absence of Spondylolisthesis: Can Interlaminar Stabilization at Single and Multi-levels Provide Sustainable Relief?

BACKGROUND: In the absence of spondylolisthesis, fusion procedures are generally not recommended. However, decompression alone often does not provide long-term clinical success of intractable leg and back pain. Decompression with interlaminar stabilization (ILS) offers a new option within the clinical continuum of care by providing a nonfusion surgical alternative. The objective of this study is to examine the sustainability of decompression with ILS and to understand the clinical success at either 1 or 2 levels as a surgical treatment for nonspondylolisthesis patients with spinal stenosis. METHODS: Under an FDA-regulated investigational device exemption (IDE) study, a total of 322 patients were enrolled in the prospective, randomized trial. This investigation focuses only on the subset of patients (116 total) from this overall cohort who were treated with decompression plus ILS at 1 or 2 levels and who did not present with spondylolisthesis preoperatively. The patients were assessed before and after surgery up to 60 months. RESULTS: At 60-month follow up, there was no statistically significant difference in ODI ≥ 15 point improvement between patient populations (81.6% of 1 level, 90.3% of 2 level). At 60 months, 83.1% of 1 level and 86.3% of 2 level patients did not require a secondary surgical procedure. At 60 months, 94.7% of 1 level and 100% of 2 level reported ≥20 mm improvement in Visual Analogue Scale leg pain. Patients reported improvement in their physical state according to Short Form-12 scores (89.3% of 1 level, 88.9% of 2 level). Patient satisfaction at 60 months was 97.4% for 1 level and 93.3% for 2 level. CONCLUSIONS: The therapeutic sustainability for the treatment of spinal stenosis without spondylolisthesis with ILS at 1 or 2 levels in the lumbar region has been shown to be safe and efficacious for patients who have failed conservative treatment. CLINICAL RELEVANCE: Decompression with ILS offers a nonterminal surgical option for the treatment of the symptomology of spinal stenosis, a progressive degenerative condition, that potentially can provide longer durability and stability than decompression alone.

The 2-Level Experience of Interlaminar Stabilization: 5-Year Follow-Up of a Prospective, Randomized Clinical Experience Compared to Fusion for the Sustainable Management of Spinal Stenosis.

BACKGROUND: To alleviate the symptoms of lumbar spinal stenosis, widely accepted methods of surgical treatment include decompression alone and decompression with fusion. As an alternative to these methods, interlaminar stabilization (ILS) devices with decompression were introduced. There is a large amount of research dedicated to examining the efficacy of ILS devices in single-level procedures, but fewer studies focus on their efficacy in 2-level procedures. The purpose of this study was to compare decompression with instrumented posterolateral fusion to decompression with interlaminar stabilization in patients who require surgical treatment at 2 levels for lumbar spinal stenosis at 5 years postoperation. METHODS: Of the 322 patients enrolled in the Investigational Device Exemption clinical trial, 116 required surgical treatment at 2 levels. The ILS group consisted of 77 patients, and the fusion group consisted of 39 patients. Efficacy was measured using composite clinical success (CCS). Patients achieve CCS if they achieve all 4 of the following outcomes: ≥15-point improvement from baseline Oswestry Disability Index (ODI); no reoperation or epidural injections; no persistent, new, or increasing neurological deficits; and no major device-related complications. RESULTS: There was a 91% rate of follow-up within the participant population in the 5-year data. There was a difference trending toward significance between groups for the absence of reoperation or epidural injection, with 68.8% of ILS patients and only 51.3% of fusion patients meeting this criteria (P = .065); 13.0% of ILS patients and 25.7% of fusion patients required secondary surgery. The percentage of patients achieving overall CCS was much greater in the ILS group than the fusion group, with 55.1% (38/69) of ILS patients and only 36.4% (12/33) of fusion patients achieving CCS at month 60 (P = .077). With regard to the ODI, the visual analog scale back and worse leg pain, the Short Form-12, and the Zurich Claudication Questionnaire, both groups had significantly better results at every follow-up time point when compared to their respective baseline scores. CONCLUSIONS: The 2-level ILS patient group performed as well as, if not better than, the 2-level fusion group across almost all outcome measures, demonstrating both clinical outcome success and favorably low reoperation rates in patients who received ILS surgery. CLINICAL RELEVANCE: This is the first 5-year analysis of the 2-level ILS experience, which supplements previous studies that describe the advantages of ILS by extending such advantages to 2-level cases.

Optimizing surface characteristics for cell adhesion and proliferation on titanium plasma spray coatings on polyetheretherketone.

BACKGROUND: Titanium plasma spray coating on polyetheretherketone (PEEK) is a recent innovation to interbody spacer technology. The inherent hydrophobic properties of standard, uncoated PEEK implants can hamper cell attachment and bone healing during fusion. The addition of titanium coating not only offers initial stability due to increased surface roughness but also long-term stability due to bony ongrowth created from osteoconductive microenvironment on the device surface. The previously established hydrophilic and osteophilic properties of commercially pure titanium (CPTi) can potentially provide an ideal environment promoting cell attachment and bony ongrowth when applied at the end plate level of the fusion site. Because the surface material composition and topography is what seems to directly affect cell adhesion, it is important to determine the ideal titanium coating for the highest effectiveness. PURPOSE: The purpose of the study is to determine whether there is an optimal surface roughness for the titanium coatings and whether different polishing methods have a greater effect than roughness or topography in mediating cell adhesion to the surface. STUDY DESIGN/SETTING: The study was divided into two phases. In Phase 1, the effects of varying surface roughnesses on identical polishing method were compared. In Phase 2, the effect of varying polishing methods was compared on identical surface roughnesses. METHODS: Coating thickness, porosity, and surface roughness were characterized using an optical microscope as per ASTM F 1854 standards. For both phases, PEEK coupons with plasma-sprayed CPTi were used, and human mesenchymal stem cells (hMSCs) at an initial density of 25,000 cells/cm2 were seeded and cultured for 24 hours before fixation in 10% formalin. The cultured hMSCs were visualized by 4',6-diamidino-2-phenylindole (DAPI) staining, a fluorescent stain that binds to the DNA of living cells. Samples were imaged using an environmental scanning electron microscope (eSEM) (Carl Zeiss Microscopy, Thornwood, NY, USA) using a backscattered detector. RESULTS: Image analysis of the CPTi coatings showed uniform and rough surfaces. For Phase 1, roughness was evaluated as fine, medium, and coarse. The eSEM image analysis and cell counting by DAPI demonstrated that hMSCs have a tendency to form stronger adhesion and greater pseudopodia extensions on fine roughness surfaces. Individual hMSCs were seen forming cytoplasmic processes extending across the width of a pore. There was a 4- and 20-fold reduction in adhered hMSCs with an increase to medium and coarse roughnesses, respectively. For Phase 2, studied groups are (1) medium CPTi coating with zirconia polishing, (2) medium CPTi coating with CPTi polishing, and (3) fine CPTi coating with CPTi polishing. The eSEM image analysis and cell counting by DAPI demonstrated that hMSCs have a tendency to form stronger adhesion and greater pseudopodia extensions on Group 3 over the other two groups. There was a twofold reduction in adhered hMSCs on medium roughness relative to fine. No difference in cell adhesion was found between Groups 1 and 2. Individual hMSCs were seen forming cytoplasmic processes extending across the width of a pore. CONCLUSIONS: Previously, it was accepted without much scrutiny that surface coatings were beneficial. This study begins to discover that surface topography directly affects the potential for cells to adhere and proliferate and lead to greater surgical efficacy.