Tumor treating fields suppress tumor cell growth and neurologic decline in models of spinal metastases.

Spinal metastases can result in severe neurologic compromise and decreased overall survival. Despite treatment advances, local disease progression is frequent, highlighting the need for novel therapies. Tumor treating fields (TTFields) impair tumor cell replication and are influenced by properties of surrounding tissue. We hypothesized that bone's dielectric properties will enhance TTFields-mediated suppression of tumor growth in spinal metastasis models. Computational modeling of TTFields intensity was performed following surgical resection of a spinal metastasis and demonstrated enhanced TTFields intensity within the resected vertebral body. Additionally, luciferase-tagged human KRIB osteosarcoma and A549 lung adenocarcinoma cell lines were cultured in demineralized bone grafts and exposed to TTFields. Following TTFields exposure, the bioluminescence imaging (BLI) signal decreased to 10%-80% of baseline, while control cultures displayed a 4.48- to 9.36-fold increase in signal. Lastly, TTFields were applied in an orthotopic murine model of spinal metastasis. After 21 days of treatment, control mice demonstrated a 5-fold increase in BLI signal compared with TTFields-treated mice. TTFields similarly prevented tumor invasion into the spinal canal and development of neurologic symptoms. Our data suggest that TTFields can be leveraged as a local therapy within minimally conductive bone of spinal metastases. This provides the groundwork for future studies investigating TTFields for patients with treatment-refractory spinal metastases.

Quantification of MRI Artifacts in Carbon Fiber Reinforced Polyetheretherketone Thoracolumbar Pedicle Screw Constructs prior to Spinal Stereotactic Radiosurgery.

PURPOSE: Carbon fiber reinforced polyetheretherketone (CFRP) is a nonmetallic material that is a subject of growing interest in the field of spinal instrumentation manufacturing. The radiolucency and low magnetic susceptibility of CFRP has potential to create less interference with diagnostic imaging compared with titanium implants. However, an objective comparison of the image artifact produced by titanium and CFRP implants has not been described. Spinal oncology, particularly after resection of spinal tumors and at the time of spinal stereotactic radiosurgery planning, relies heavily on imaging interpretation for evaluating resection, adjuvant treatment planning, and surveillance. We present a study comparing measurements of postoperative magnetic resonance imaging artifacts between titanium and CFRP pedicle screw constructs in the setting of separation surgery for metastatic disease. METHODS AND MATERIALS: The diameter of the signal drop around the screws (pedicle screw artifact) and the diameter of the spinal canal free from artifacts (canal visualization) were measured in consecutive patients who had spinal instrumentation followed by spinal stereotactic radiosurgery in the June 2019 to May 2022 timeframe. The spinal cord presented a shift at the screw level in sagittal images which was also measured (Sagittal Distortion, SagD). RESULTS: Fifty patients, corresponding to 356 screws and 183 vertebral levels, were evaluated overall. CFRP produced less artifacts in all the 3 parameters compared with titanium: mean pedicle screw artifact (CFRP = 5.8 mm, Ti = 13.2 mm), canal visualization (CFRP = 19.2 mm, Ti = 15.5 mm), and SagD (CFRP = .5 mm, Ti = 1.9 mm), all P < .001. In practice, these findings translate into better-quality magnetic resonance imaging. CONCLUSIONS: The initial perceived advantages are easier evaluation of postoperative imaging, facilitating radiation treatment planning, recurrence detection, and avoidance in repeating a suboptimal computed tomography myelogram. Further clinical studies analyzing long-term outcomes of patients treated with CFRP implants are necessary.

Anatomy of the posterior Fossa: a comprehensive description for pediatric brain tumors.

Posterior fossa tumors are the most common pediatric brain tumors, and present unique challenges in terms of their location and surgical management. The posterior fossa comprehends complex anatomy and represents the smallest and deepest of the three cranial base fossae. An in-depth understanding of posterior fossa anatomy is crucial when it comes to the surgical resection of pediatric brain tumors. Mastering the knowledge of posterior fossa anatomy helps the neurosurgeon in achieving a maximal and safe volumetric resection, that impacts in both overall and progression free survival. With the advancements in microsurgery, the telovelar approach has emerged as the workhorse technique for the resection of posterior fossa tumors in pediatric patients. This approach involves meticulously dissecting of the natural clefts present in the cerebellomedullary fissure, making a comprehensive understanding of the underlying anatomy key for its success.

An Overview of Robotic Colorectal Surgery Adoption and Training in Brazil.

Background and Objectives: Robotic surgical systems have rapidly become integrated into colorectal surgery practice in recent years, particularly for rectal resections, where the advantages of robotic platforms over conventional laparoscopy are more pronounced. However, as with any technological advancement, the initial high costs can be a limiting factor, leading to unequal health service access, especially in middle- and lower-income countries. Materials and Method: A narrative review was conducted with the objective of providing an overview of the escalating adoption, current training programmes, and certification process of robotic colorectal surgery in Brazil. Results: Brazil has witnessed a rapid increase in robotic platforms in recent years. Currently, there are 106 robotic systems installed nationwide. However, approximately 60% of the medical facilities which adopted robotic platforms are in the Southeast region, which is both the most populous and economically prosperous in the country. The Brazilian Society of Coloproctology recently established clear rules for the training programme and certification of colorectal surgeons in robotic surgery. The key components of the training encompass theoretical content, virtual robotic simulation, observation, assistance, and supervised procedures in colorectal surgery. Although the training parameters are well established, no colorectal surgery residency programme in Brazil has yet integrated the teaching and training of robotic surgery into its curriculum. Thus far, the training process has been led by private institutions and the industry. Conclusion: Despite the fast spread of robotic platforms across Brazil, several challenges still need to be addressed to democratise training and promote the widespread use of these platforms. It is crucial to tackle these obstacles to achieve greater integration of robotic technology in colorectal surgery throughout the country.

Lateral ventricle subependymoma resected with a transcallosal approach: illustrative case.

BACKGROUND: Subependymomas are World Health Organization grade I tumors, and 30% occur in the lateral ventricles. Surgery is the mainstay of treatment, and the transcallosal or transcortical/transsulcal approaches are preferred for those tumors occurring near the foramen of Monro or atrium. Visualization, proximity to the fornix and basal ganglia, hydrocephalus, and brain retraction during surgery make these operations challenging. The authors present the case of a 65-year-old male with a subependymoma located in the left lateral ventricle. The tumor was completely resected using an interhemispheric/transcallosal approach. OBSERVATIONS: The authors analyze the anatomopathological features of subependymoma, along with the clinical behavior and therapeutic options. The authors discuss in detail the advantages and disadvantages of the interhemispheric/transcallosal approach for resection of these tumors. LESSONS: Subependymomas are slow-growing lesions with an indolent yet complicated course making surgical removal challenging yet feasible using the correct techniques. The interhemispheric transcallosal approach offers an excellent route for the resection of large subependymomas, but there is still a significant risk for postoperative complications.

Carbon Fiber-Reinforced Polyetheretherketone Spinal Implants for Treatment of Spinal Tumors: Perceived Advantages and Limitations.

PURPOSE: Carbon-fiber reinforced polyetheretherketone (CFRP)-based spinal implants are an alternative to titanium, offering less image artifact as their metallic counterparts while maintaining similar biomechanical and biocompatibility properties. Its use in the management of spinal tumors has been reported, however the perceived advantages related to improved imaging quality, radiation treatment planning, and detection of tumor recurrence have not been fully assessed. METHODS: We performed a retrospective review of medical records amongst oncologic patients treated at MD Anderson Cancer Center with CFRP implants. Histology, tumor location, construct features, time of follow-up, adjuvant radiation, recurrences, overall survival, and hardware-related complications were recorded. RESULTS: Sixty-nine consecutive patients were assessed (22 primary tumors, 47 metastases) and the median time for follow-up was 5.4 months. Amongst the cohort, a total of 491 CFRP pedicle screws were implanted. Hardware complications were observed in 5 cases (7.04%). Adjuvant radiation was completed in 8 patients with primary tumors and 29 patients with spinal metastases. A total of 28 patients (40.5%) from the combined primary and metastatic cohorts experienced systemic disease progression, with 12 patients (17.3%) demonstrating local recurrences. Amongst primary and metastatic tumors, overall survival (p = 0.363) and rate of local recurrence (p = 0.112) were similar. CONCLUSION: This largest series of CFRP implants demonstrates safe and effective spinal stabilization for patients with both primary and metastatic tumors. Enhanced postoperative imaging led to minimal imaging artifacts which facilitated postoperative radiation planning and the ability to detect local recurrence.

Pneumoretroperitoneum and Sepsis After Transanal Endoscopic Resection of a Rectal Lateral Spreading Tumor.

Transanal endoscopic microsurgery is considered a safe, appropriate, and minimally invasive approach, and complications after endoscopic microsurgery are rare. We report a case of sepsis and pneumoretroperitoneum after resection of a rectal lateral spreading tumor. The patient presented with rectal mucous discharge. Colonoscopy revealed a rectal lateral spreading tumor. The patient underwent an endoscopic transanal resection of the lesion. He presented with sepsis of the abdominal focus, and imaging tests revealed pneumoretroperitoneum. A new surgical intervention was performed with a loop colostomy. Despite the existence of other reports on pneumoretroperitoneum after transanal endoscopic microsurgery, what draws attention to this case is the association with sepsis.

Do young patients have different clinical presentation of colorectal cancer causing delay in diagnosis?

PURPOSE: The incidence of colorectal cancer is increasing among young patients. In these patients, colorectal cancer is believed to have a poorer prognosis because it is more aggressive and diagnosed at later stages; however, the behavior of these tumors in young patients remains to be elucidated. We investigated the impact of time interval between onset of symptoms and diagnosis (TISD) at the pathologic stage of colorectal cancer in young patients. METHODS: The medical records of 215 patients with colorectal adenocarcinoma were reviewed. Patients were divided into two groups according to age. The young group (age < 50 years) consisted of 66 patients, and the older group (age ≥ 50 years) of 149 patients. Clinical variables, TISD, pathologic stage, operative mortality, and oncologic outcomes were compared between groups. RESULTS: The older group had less abdominal pain (74.0 vs. 56.0 %, p = 0.0129). In multivariate analysis, the following variables were independently associated with tumor pathologic stage: personal history of inflammatory bowel disease (p < 0.0001), family history of familial adenomatous polyposis (p = 0.00100), and smoking (p = 0.0070). Both groups had similar rates regarding pathologic stage (I, 15 vs. 22 %; II, 22 vs. 24 %; III, 27 vs. 16 %; IV, 37 vs. 38 %, p = 0.3380). There was no difference in overall survival [45 (69 %) vs. 84 (61 %), p = 0.2482] and cancer-free survival [36 (63 %) vs. 83 (62 %), p = 0.9218] between groups. CONCLUSIONS: Young patients with colorectal cancer had clinical and pathological presentation similar to that of older patients.

Anorectal manometry evaluation in adult women with clinical and urodynamic diagnostics of overactive bladder.

BACKGROUND: Anorectal manometry is a diagnostic method often used in clinical practice for assessing functional anorectal disorders and pelvic floor. The dysfunctional voiding, anorectal and pelvic floor has been considered as contributing factors of the symptoms of overactive bladder. AIM: To evaluate the results with anorectal manometry in adult women with clinical and urodynamic diagnostics of overactive bladder. METHODS: Twenty-five adult women (mean age 45.5 ± 11.9 years) with clinical and urodynamic diagnostic of overactive bladder underwent anorectal manometry and the results of this assessment were compared to a control group of eighteen women (mean age 33.9 ± 10.7 years) with no urinary or intestinal disorders and without clinical criteria for diagnosis of overactive bladder. RESULTS: Paradoxical puborectalis contraction occurred in six patients in the overactive bladder group and none of the controls. There were no significant between group differences in the following manometric parameters: rectoanal inhibitory reflex, rectal sensitivity, maximum tolerable volume, resting pressure, and hypertonia at rest. Mean squeeze pressure was 182.2 mmHg in the overactive bladder group versus 148.1 mmHg in the control group. CONCLUSION: Women with overactive bladder had increased incidence of paradoxical puborectalis contraction than women in the control group.