Subtotal Resection Group Research Articles

Deep learning radiomic nomogram outperforms the clinical model in distinguishing intracranial solitary fibrous tumors from angiomatous meningiomas and can predict patient prognosis.

To evaluate the value of a magnetic resonance imaging (MRI)-based deep learning radiomic nomogram (DLRN) for distinguishing intracranial solitary fibrous tumors (ISFTs) from angiomatous meningioma (AMs) and predicting overall survival (OS) for ISFT patients. In total, 1090 patients from Beijing Tiantan Hospital, Capital Medical University, and 131 from Lanzhou University Second Hospital were categorized as primary cohort (PC) and external validation cohort (EVC), respectively. An MRI-based DLRN was developed in PC to distinguish ISFTs from AMs. We validated the DLRN and compared it with a clinical model (CM) in EVC. In total, 149 ISFT patients were followed up. We carried out Cox regression analysis on DLRN score, clinical characteristics, and histological stratification. Besides, we evaluated the association between independent risk factors and OS in the follow-up patients using Kaplan-Meier curves. The DLRN outperformed CM in distinguishing ISFTs from AMs (area under the curve [95% confidence interval (CI)]: 0.86 [0.84-0.88] for DLRN and 0.70 [0.67-0.72] for CM, p < 0.001) in EVC. Patients with high DLRN score [per 1 increase; hazard ratio (HR) 1.079, 95% CI: 1.009-1.147, p = 0.019] and subtotal resection (STR) [per 1 increase; HR 2.573, 95% CI: 1.337-4.932, p = 0.004] were associated with a shorter OS. A statistically significant difference in OS existed between the high and low DLRN score groups with a cutoff value of 12.19 (p < 0.001). There is also a difference in OS between total excision (GTR) and STR groups (p < 0.001). The proposed DLRN outperforms the CM in distinguishing ISFTs from AMs and can predict OS for ISFT patients. The proposed MRI-based deep learning radiomic nomogramoutperforms the clinical modelin distinguishing ISFTs from AMs and can predict OS of ISFT patients, which could guide the surgical strategy and predict prognosis for patients. Distinguishing ISFTs from AMs based on conventional radiological signs is challenging. The DLRN outperformed the CM in our study. The DLRN can predict OS for ISFT patients.

Treatment Strategies and Long-Term Outcomes in Silent Corticotroph Adenomas: A Single-Center Retrospective Study of 367 Cases.

Silent corticotroph adenoma (SCA) is a high-risk pituitary neuroendocrine tumor (PitNET) which exhibits more aggressive behavior than other nonfunctioning PitNETs. Some SCAs are observed to recur after total resection (TR). We aim to discuss the long-term outcomes after endoscopic endonasal surgery for SCAs and explore optimal treatment after operation. Clinical data and intraoperative videos from 367 SCAs who underwent endoscopic endonasal surgery were retrospectively collected. Patients were categorized into TR and subtotal resection (STR) groups according to 3-month postoperative MRIs. Based on close-up intraoperative observation of the relationship between tumor and pituitary gland, diaphragm, and medial wall cavernous sinus, patients in the TR group were further subdivided into gross total resection (GTR) and near total resection (NTR) groups. Patients in the STR group were subdivided as STR followed by observation (STR + ob) and STR followed by adjuvant stereotactic radiosurgery (SRS) (STR + SRS). Kaplan-Meier analysis was used to compare the event-free survival among these subgroups. Headache (27.5%) and vision loss (55.3%) were the most common presenting symptoms. Cavernous sinus (CS) invasion was confirmed intraoperatively in 167 (45.5%) patients. After operation, 175 (47.7%), 83 (22.6%), 32 (8.7%), and 77 (21%) patients were divided into GTR, NTR, STR + ob, and STR + SRS groups, respectively. The mean follow-up time was 40.9 ± 25.8 months. There were 0, 17 (20.5%), 9 (28.1%), and 4 (5.2%) patients noted to have PitNET recurrence or progression in GTR, NTR, STR + ob, and STR + SRS groups, respectively. Event-free survival distribution in the NTR group was similar to that in the STR + ob group (P = .696), which was significantly lower than that in the STR + SRS group (P = .008). Adrenocorticotropic hormone (ACTH)-negative SCAs have lower preoperative ACTH levels and were more likely to invade CS than ACTH-positive SCAs. CS invasion was commonly seen in SCAs, often precluding GTR. Radical surgery and close follow-up were proposed. Early postoperative adjuvant SRS for remnant tumor should be considered.

Patient-Centered Neurosurgery: Improved Outcomes after Subtotal Surgical Resection and Nonframe-Based Fractionated Stereotactic Radiotherapy for Large Cerebellopontine Angle Vestibular Schwannoma

Abstract Background The novel paradigm in neurosurgery for large vestibular schwannomas (VSs) involves a combination of planned subtotal resection (STR) and scheduled postoperative fractionated stereotactic radiotherapy (FSRT). Methods This retrospective observational study aimed to evaluate and compare the outcomes of patients who underwent either near-total resection (NTR) or were treated with STR and scheduled FSRT over 6 years. We systematically coded and analyzed the data to obtain comprehensive insights into the results. Results Our study included 65 patients diagnosed with large VS, who underwent retrosigmoid craniotomy and NTR or STR for tumor removal. The mean age of the cohort was 42.6 (standard deviation: 16.2) years, with 40 (61.5%) female patients. All patients presented with asymmetrical sensory neural hearing loss and other prevalent symptoms such as headache (58) and tinnitus (58). Cerebellar signs, speech abnormalities, and pyramidal signs were also observed. Ten patients underwent NTR, and 55 underwent STR followed by an FSRT at 3 months or later based on the physical and radiological findings. Facial nerve palsy was noted in all cases of those who underwent NTR, while no instances of facial nerve palsy, lower cranial nerve palsy, posterior fossa, or brain stem injury were noted in the STR group. One patient undergoing STR experienced meningitis and died despite best possible medical management. The majority of patients showed symptom improvement, and none of the patients reported recurrence at 3-year follow-up. Conclusion The combined approach of STR and FSRT ensures safety, high tumor control rates, and favorable outcomes. It provides a sensible alternative to NTR for managing large tumors, emphasizing tumor debulking while preserving neurological function for overall benefit.

The role of surgery in recurrent ependymomas.

The role of surgery in recurrent ependymomas and its contribution to the outcome are not well defined. While gross-total resection (GTR) has shown benefit in newly diagnosed patients with improvement in progression-free survival (PFS), its impact after recurrence is not known. Its role in distant relapses or multiple local recurrences is similarly less well understood. The objective of this study was to investigate whether GTR could prolong survival after recurrence. In this paper, the authors identified patients with ependymomas who underwent surgery at Texas Children's Hospital for recurrent ependymomas between December 2000 and December 2021. Surgical treatment was stratified as GTR, subtotal resection (STR), or a biopsy. Kaplan-Meier analysis was performed for PFS and overall survival (OS), and the log-rank test was used to assess statistical significance. The Cox regression model was used for multivariable analysis. Forty children were identified with a first ependymoma recurrence and follow-up data were collected. The median age was 5.46 years (95% CI 4.52-6.39 years) with a mean follow-up of 3.92 years (95% CI 2.42-5.42 years). In 26 patients (65%), the original tumor was located in the infratentorial space. Twenty-nine patients (72.5%) presented with local recurrence. Within this group, the 5-year PFS rates for the GTR and STR groups were 40.1% and 26.8%, respectively. The 5- and 10-year OS rates were 58.3% and 50% in the GTR group and 51% and 16.7% in the STR group, respectively. Fifteen patients presented with a second recurrence. The 5-year PFS and OS rates in patients who had GTR after a second recurrence were 33% and 50%, respectively. GTR of local recurrent ependymomas can result in long-term survival in first and second recurrences. Further and larger studies are necessary to elucidate the role of surgery in distal recurrences.

Meningioma involving the superior sagittal sinus: long-term outcome after robotic radiosurgery in primary and recurrent situation.

Treatment for meningiomas involving the superior sagittal sinus (SSS) is challenging and proved to be associated with higher risks compared to other brain locations. Therapeutical strategies may be either microsurgical (sub-)total resection or adjuvant radiation, or a combination of both. Thrombosis or SSS occlusion following resection or radiosurgery needs to be further elucidated to assess whether single or combined treatment is superior. We here present tumor control and side effect data of robotic radiosurgery (RRS) in combination with or without microsurgery. From our prospective database, we identified 137 patients with WHO grade I meningioma involving the SSS consecutively treated between 2005 and 2020. Treatment decisions were interdisciplinary. Patients underwent RRS as initial/solitary treatment (group 1), as adjuvant treatment after subtotal resection (group 2), or due to recurrent tumor growth after preceding microsurgery (group 3). Positive tumor response was assessed by MRI and defined as reduction of more than 50% of volume. Study endpoints were time to recurrence (TTR), time to RRS, risk factors for decreased survival, and side effects. Overall and specific recurrence rates for treatment groups were analyzed. Side effect data included therapy-related morbidity during follow-up (FU). A total of 137 patients (median age, 58.3 years) with SSS meningiomas WHO grade I were analyzed: 51 patients (37.2%) in group 1, 15 patients (11.0%) in group 2, and 71 patients (51.8%) in group 3. Positive MR (morphological response) to therapy was achieved in 50 patients (36.4%), no response was observed in 25 patients (18.2%), and radiological tumor progression was detected in 8 patients (5.8%). Overall 5-year probability of tumor recurrence was 15.8% (median TTR, 41.6 months). Five-year probabilities of recurrence were 0%, 8.3.%, and 21.5% for groups 1-3 (p = 0.06). In multivariate analysis, tumor volume was significantly associated with extent of SSS occlusion (p = 0.026) and sex (p = 0.011). Tumor volume significantly correlated with TTR (p = 0.0046). Acute sinus venous thrombosis or venous congestion-associated bleedings did not occur in any of the groups. RRS for grade I meningiomas with SSS involvement represents a good option as first-line treatment, occasionally also in recurrent and adjuvant scenarios as part of a multimodal treatment strategy.

Surgical outcomes and risk factors for recurrence of myxopapillary ependymoma: a single-center experience.

Myxopapillary ependymomas (MPEs) are low-grade, well-circumscribed tumors that often involve the conus medullaris, cauda equina, or filum terminale. They account for up to 5% of all tumors of the spine and 13% of spinal ependymomas, with a peak incidence between 30 and 50 years of age. Because of the rarity of MPEs, their clinical course and optimal management strategy are not well defined, and long-term outcomes remain difficult to predict. The objective of this study was to review long-term clinical outcomes of spinal MPEs and identify factors that may predict tumor resectability and recurrence. Pathologically confirmed cases of MPE at the authors' institution were identified and medical records were reviewed. Demographics, clinical presentation, imaging characteristics, surgical technique, follow-up, and outcome data were noted. Two groups of patients-those who underwent gross-total resection (GTR) and those who underwent subtotal resection (STR)-were compared using the Mann-Whitney U-test for continuous and ordinal variables and the Fisher exact test for categorical variables. Differences were considered statistically significant at p ≤ 0.05. Twenty-eight patients were identified, with a median age of 43 years at the index surgery. The median postoperative follow-up duration was 107 months (range 5-372 months). All patients presented with pain. Other common presenting symptoms were weakness (25.0%), sphincter disturbance (21.4%), and numbness (14.3%). GTR was achieved in 19 patients (68%) and STR in 9 (32%). Preoperative weakness and involvement of the sacral spinal canal were more common in the STR group. Tumors were larger and spanned more spinal levels in the STR group compared with the GTR cohort. Postoperative modified McCormick Scale grades were significantly higher in the STR cohort compared with the GTR group (p = 0.00175). Seven of the 9 STR patients (77.8%) underwent reoperation for recurrence at a median of 32 months from the index operation, while no patients required reoperation after GTR, for an overall reoperation rate of 25%. Findings of this study emphasize the importance of tumor size and location-particularly involvement of the sacral canal-in determining resectability. Reoperation for recurrence was necessary in 78% of patients with subtotally resected tumors; none of the patients who underwent GTR required reoperation. Most patients had stable neurological status postoperatively.

Analysis of Early Outcomes of Pencil Beam Proton Therapy Compared with Passive Scattering Proton Therapy for Clival Chordoma

To assess the early outcomes of the following 2 types of proton therapy: passive scattering proton therapy (PSPT) and pencil beam proton therapy (PBPT). The consecutive patients who had surgery in our facility were retrospectively reviewed. Thirty-two patients were identified (PBPT 22 patients [69%]). The mean (±standard deviation [SD]) tumor size was 3.8±1.8cm, and the most common location was the upper clivus (41%). Four cases (13%) were revision surgeries referred from elsewhere, and 2 cases underwent additional surgery elsewhere to achieve near-total resection before radiation. The cerebrospinal fluid leak occurred in 3 patients (9%). The mean (±SD) prescribed dose of PSPT and PBPT was 74±3Gy and 72±3Gy, respectively (P= 0.07). The mean (±SD) fractionation of PSPT and PBPT was 39±2 and 36±2, respectively (P= 0.001). Radiation toxicities were recorded in endocrine (11 patients [34%]), ophthalmic (3 patients [9%]), otologic (7 patients [22%]), and radiation necrosis (4 patients [13%]). PSPT was associated with endocrinopathy (odds ratio [OR], 10.5; 95% confidence interval, 1.86-59.4, P= 0.008), and radiation dose was associated with otologic toxicity (OR 1.57; 95% confidence interval, 1.02-2.44; P= 0.04). The gross-near total resection group had better progression-free survival than the subtotal resection group regardless of radiation therapy (P= 0.01). Overall, 3-year progression-free survival was 73%, and 5-year overall survival was 93%. The PBPT group showed comparable outcome to the PSPT group. The degree of resection was more important than the modality of proton therapy. Further follow-up and cases are necessary to evaluate the benefit of PBPT.

SURG-25. PATTERNS OF RECURRENCES ACCORDING TO THE EXTENT OF RESECTION IN PARIETNS WITH GLIOBLASTOMA, IDH-WILDTYPE: A RETROSPECTIVE STUDY

Abstract OBJECTIVE In glioblastoma (GBM) patients, controlling the microenvironment around the tumor using various treatment modalities, including surgical intervention, is essential in determining the outcome of treatment. This study was conducted to elucidate whether recurrence patterns differ according to the extent of resection (EOR) and whether this difference affects prognosis. METHODS This single-center study included 358 eligible patients with histologically confirmed isocitrate dehydrogenase (IDH)-wild-type GBM from November 1, 2005, to December 31, 2018. Patients were assigned to one of three separate groups according to EOR: supratotal resection (SupTR), gross-total resection (GTR), and subtotal resection (STR) groups. The patterns of recurrence were classified as local, marginal, and distant based on the range of radiation. The relationship between EOR and recurrence pattern was statistically analyzed. RESULTS Observed tumor recurrence rates for each group were as follows: SupTR group, 63.4%; GTR group, 75.3%; and STR group, 80.5% (p = 0.072). Statistically significant differences in patterns of recurrences among groups were observed with respect to local recurrence (SupTR, 57.7%; GTR, 76.0%; STR, 82.8%; p = 0.036) and distant recurrence (SupTR, 50.0%; GTR, 30.1%; STR, 23.2%; p = 0.028). Marginal recurrence showed no statistical difference between groups. Both overall survival and progression-free survival were significantly increased in the SupTR group compared with the STR and GTR groups (p &amp;lt; 0.0001). CONCLUSIONS In this study, the authors investigated the association between EOR and patterns of recurrence in patients with IDH-wild-type GBM. The findings not only show that recurrence patterns differ according to EOR but also provide clinical evidence supporting the hypothesized mechanism by which distant recurrence occurs.

Patterns of recurrence according to the extent of resection in patients with IDH-wild-type glioblastoma: a retrospective study.

In glioblastoma (GBM) patients, controlling the microenvironment around the tumor using various treatment modalities, including surgical intervention, is essential in determining the outcome of treatment. This study was conducted to elucidate whether recurrence patterns differ according to the extent of resection (EOR) and whether this difference affects prognosis. This single-center study included 358 eligible patients with histologically confirmed isocitrate dehydrogenase (IDH)-wild-type GBM from November 1, 2005, to December 31, 2018. Patients were assigned to one of three separate groups according to EOR: supratotal resection (SupTR), gross-total resection (GTR), and subtotal resection (STR) groups. The patterns of recurrence were classified as local, marginal, and distant based on the range of radiation. The relationship between EOR and recurrence pattern was statistically analyzed. Observed tumor recurrence rates for each group were as follows: SupTR group, 63.4%; GTR group, 75.3%; and STR group, 80.5% (p = 0.072). Statistically significant differences in patterns of recurrences among groups were observed with respect to local recurrence (SupTR, 57.7%; GTR, 76.0%; STR, 82.8%; p = 0.036) and distant recurrence (SupTR, 50.0%; GTR, 30.1%; STR, 23.2%; p = 0.028). Marginal recurrence showed no statistical difference between groups. Both overall survival and progression-free survival were significantly increased in the SupTR group compared with the STR and GTR groups (p < 0.0001). In this study, the authors investigated the association between EOR and patterns of recurrence in patients with IDH-wild-type GBM. The findings not only show that recurrence patterns differ according to EOR but also provide clinical evidence supporting the hypothesized mechanism by which distant recurrence occurs.

Resection and radiotherapy for intracranial ependymoma: a multiinstitutional 50-year experience.

Maximal safe resection is the standard-of-care treatment for adults with intracranial ependymoma. The value of adjuvant radiotherapy remains unclear as these tumors are rare and current data are limited to a few retrospective cohort studies. In this study, the authors assembled a cohort of patients across multiple international institutions to assess the utility of adjuvant radiotherapy in this patient population. Adults with intracranial ependymoma managed surgically at the University Health Network in Toronto, Canada, the University of Oklahoma Health Sciences Center in Oklahoma City, Oklahoma, and The Ottawa Hospital in Ottawa, Canada, were included in this study. The primary end points were progression-free survival (PFS) and overall survival (OS). Clinicopathological variables were assessed in univariate and multivariate Cox proportional hazard models for prognostic significance of PFS and OS. A total of 122 patients diagnosed between 1968 and 2019 were identified for inclusion. The majority of patients had grade II ependymomas on histopathology (78%) that were infratentorially located (71%), underwent gross-total (GTR) or near-total resection (NTR; 55%), and were treated with adjuvant radiotherapy (67%). A volumetric analysis of the extent of resection in 49 patients with available tumor volume data supported the accuracy of the categorical GTR, NTR, and subtotal resection (STR) groups utilized. Independent statistically significant predictors of poorer PFS in the multivariate analysis included STR or biopsy (vs GTR/NTR; HR 5.4, 95% confidence interval [CI] 2.4-11.0, p < 0.0001) and not receiving adjuvant radiotherapy; cranial (HR 0.5, 95% CI 0.2-1.1) and craniospinal (HR 0.2, 95% CI 0.04-0.5) adjuvant radiotherapy regimens improved PFS (p = 0.0147). Predictors of poorer OS in the multivariate analysis were grade III histopathology (vs grade II: HR 5.7, 95% CI 1.6-20.2, p = 0.0064) and undergoing a biopsy/STR (vs GTR/NTR: HR 9.8, 95% CI 3.2-30.1, p = 0.0001). The results of this 50-year experience in treating adult intracranial ependymomas confirm an important role for maximal safe resection (ideally GTR or NTR) and demonstrate that adjuvant radiotherapy improves PFS. This work will guide future studies as testing for molecular ependymoma alterations become incorporated into routine clinical practice.

Clinical Outcomes and Prognostic Analysis of 101 Patients of Central Neurocytoma: A 10-Year Treatment Experience at a Single Institution

ObjectiveCentral neurocytoma (CN) is a rare type of tumor that currently lacks an optimal treatment protocol. This study aimed to explore the clinical outcomes of CN in a cohort of 101 patients and identify prognostic factors associated with multiple treatment modalities.MethodsThis monocentric study retrospectively analyzed the clinical data of 101 CN patients who underwent surgical resection. The patients were followed up, and their overall survival (OS) and progression-free survival (PFS) were calculated.ResultsFor the entire cohort, the 5- and 10-year OS rates were 88.7% and 82.8%, respectively, and the 5- and 10-year PFS rates were 86.5% and 64.9%, respectively. Of the 82 (81.19%) patients with CN who underwent gross total resection (GTR), 28 (28/82, 34.1%) also received radiotherapy (RT). Of the 19 (18.81%) patients with CN who underwent subtotal resection (STR), 11 (11/19, 57.9%) also received RT or stereotactic radiosurgery (SRS). Compared to STR, GTR significantly improved the 5-year OS (92.4% vs. 72.4%, P=0.011) and PFS (92.4% vs. 60.4%, P=0.009) rates. Radiotherapy did not affect OS in the GTR group (p=0.602), but it had a statistically significant effect on OS in the STR group (P<0.001). However, the OS (P=0.842) and PFS (P=0.915) in the STR plus radiotherapy group were comparable to those in the GTR alone group. Compared to STR alone, STR plus radiotherapy improved the 5-year PFS rate from 25% to 75% in patients with atypical CN (P=0.004). Cox regression models and a competing risk model showed that the removal degree and radiotherapy were independent prognostic factors for survival. With improvements in modern radiotherapy techniques, severe radiotherapy toxicity was not observed.ConclusionOur findings support the use of GTR whenever possible. Radiotherapy can improve the prognosis of patients who undergo STR, especially in atypical CNs having a higher tendency to relapse. Close imaging follow-up is necessary. Our findings will help clinicians to select optimal, individualized treatment strategies to improve OS and PFS for patients with CN.

Is Postoperative Radiotherapy Needed in the Management of Adult Craniopharyngiomas?

The optimal treatment of adult craniopharyngioma (CP) remains controversial. Although benign, these tumors tend to recur locally. The choice between gross total resection (GTR) versus subtotal resection (STR) with adjuvant or delayed radiotherapy (RT) is debated. The objective of this study is to review our experience with adult CPs over a 20-year period and identify an optimal management strategy. From 1999 to 2020, we reviewed all patients diagnosed with CP at our institution. We collected data regarding tumor characteristics, treatments, and toxicity. Disease progression was defined as growth on imaging. Descriptive statistics were used to assess patient characteristics. The Kaplan Meier method was used to assess progression-free survival (PFS) and corresponding 95% confidence intervals (CI) from the time since treatment initiation. Twenty-four patients with a median age of 50 were included in this study. The median follow-up was 85 months. Seven patients had initial GTR, 10 STR, and 7 STR + RT. The overall 5-year PFS was 56% (95% CI: 38-83%): 100% in the STR + RT group, 69% in the GTR group, and 18% in the STR group (p = 0.01). Of the 17 patients initially treated with surgery alone, 3 with GTR and 6 with STR required salvage RT at a median of 46 months, with no further progression after salvage RT. Our study underscores the importance of RT for local control and suggests that STR + RT should be considered a viable option in the management of these tumors as it may be associated with improved PFS compared to surgery alone.

Surgical Outcomes of Clival Chordoma Through Endoscopic Endonasal Approach: A Single-Center Experience.

ObjectiveClival chordoma is a locally aggressive tumor with low metastatic potential. In the past decade, endoscopic endonasal approach (EEA) for clival chordoma has had a higher resection rate and a lower morbidity rate than transcranial approaches. Here, we present our initial single-center experience after EEA of clival chordomas.Patients and methodsThis study retrospectively analyzed 17 consecutive patients with clival chordoma who received EEA in our department between March 2015 and September 2021. The operation was performed by a single surgeon with EEA. The clinical and pathological characteristics were analyzed along with the surgical outcomes and complications.ResultsA total of 17 consecutive patients with clival chordoma received EEA with a median follow-up of 29.2 months (range 1-79). Gross total resection (GTR) was performed in 7 cases (41%), subtotal resection (STR) in 7 case (41%) and partially resection (PR) in 3 cases (18%). Cerebrospinal fluid leakage occurred in 2 cases (12%) and meningitis developed in 3 patients (18%) which were all successfully treated with intravenous antibiotics without any complications. There were no perioperative deaths or new focal neurological deficits postoperatively. Four in 7 patients with STR have had radiotherapy while the other three chose to be monitored. Till the last follow-up, three patients in STR group who received radiotherapy (3 in 4) had no tumor regrowth, while one in STR group with radiotherapy (1 in 4) showed tumor progression. Two patients in STR group without radiotherapy (2 in 3) showed stable tumor while the left one (1 in 3) showed tumor progression. One patient in the PR group died of tumor progression 2 years postoperation and the other one showed tumor progression and died of lung cancer 1 year postoperation. In addition, 1 in 7 patients with GTR had tumor recurrence in situ after 10 months and developed surgical pathway seeding in the spinal canal in C1 after 16 months. No recurrence occurred in the other 6 cases with GTR during the follow-up.ConclusionAlthough more cases are needed, our case series showed EEA is a safe and reliable method for clival chordoma with high resection rates and low morbidity rates. GTR without tumor residuum would improve the outcome.

Fate of Residual Tumor After Subtotal Resection of a Previously Irradiated Vestibular Schwannoma: Long-Term Follow-Up of a Single-Institutional Series

The fate of residual tumor after salvage surgery for recurrent vestibular schwannoma (VS) after radiosurgery has not been elucidated so far. We reviewed our surgical series of salvage surgery for recurrent VS, with focus on the natural history of the residual tumor after salvage surgery. This study enrolled 14 patients who underwent salvage surgical resection in our institute and were followed up for >12months. The study included 3 men and 11 women with a median age of 55years (range: 16-70years). The median pre-stereotactic radiosurgery tumor volume was 6591mm3. All patients were treated using gamma knife radiosurgery. The median duration from gamma knife radiosurgery to surgery was 52months (range: 10-116months). Solid tumor growth and cyst formation were observed in 6 (42.9%) and 8 (57.1%) patients, respectively. Subtotal resection and partial resection were performed in 13 (92.8%) patients, and gross total resection was achieved in only one (7.2%) patient. Postoperative facial paresis and surgical complication occurred in 5 (35.7%) and 2 (14.3%) patients, respectively. After salvage resection for irradiated VS, no patient showed tumor progression or recurrence during the follow-up period (13 subtotal/partial resections and 1 total resection). In addition, 2 patients in the subtotal resection group showed residual tumor shrinkage after salvage surgery during the follow-up period. The behavior of residual tumors after salvage surgery for irradiated VS was stable. Adjuvant treatment for these residual tumors may not be necessary.

Surgical Outcomes of Sphenoid Wing Meningioma with Periorbital Invasion.

ObjectiveThe aim of this study was to evaluate the clinical outcome of sphenoid wing meningioma with periorbital invasion (PI) after operation. MethodsSixty one patients with sphenoid wing meningioma were enrolled in this study. Their clinical conditions were monitored after the operation and followed up more than 5 years at the outpatient clinic of a single institution. Clinical and radiologic information of the patients were all recorded including the following parameters : presence of PI, presence of peri-tumor structure invasion, pathologic grade, extents of resection, presence of hyperostosis, exophthalmos index (EI), and surgical complications. We compared the above clinical parameters of the patients with sphenoid wing meningioma in the presence or absence of PI (non-PI), then linked the analyzed data with the clinical outcome of the patients. ResultsOf 61 cases, there were 14 PI and 47 non-PI patients. PI group showed a significantly higher score of EI (1.37±0.24 vs. 1.00±0.01, p<0.001), more frequent presence of hyperostosis (85.7% vs. 14.3%, p<0.001), and lower rate of gross total resection (GTR) (35.7% vs. 68.1%, p=0.032). The lower score of pre-operative EI, the absence of both PI and hyperostosis, smaller tumor size, and the performance of GTR were associated with lower recurrence rates in the univariate analysis. However, in the multivariate analysis, the performance of GTR was the only significant factor to determine the recurrence rate (p=0.043). The incidences of surgical complications were not statistically different between the subtotal resection (STR) and GTR groups, but it was strongly associated tumor size (p=0.017). ConclusionThe GTR group showed lower recurrence rate than the STR group without differences in the surgical complications. Therefore, the GTR is strongly recommended to treat sphenoid wing meningioma with PI for the better clinical outcome.

Posterior fossa epidermoid tumors: a single-center study and proposed classification system

Background Epidermoid tumors of the cerebellopontine angle and posterior fossa account for approximately 1% of all intracranial tumors. Classifications that may guide surgical planning in the current neurosurgical practice are lacking. This study aimed to focus on the surgical outcome and suggest a classification system that may aid neurosurgeons in determining the goal of resection to minimize morbidity and mortality rates. Methods The study population comprised patients who underwent surgery and follow-up for tissue-proven epidermoid tumors between 2015 and 2020. Patients’ data, including demographic features, clinical symptomatology, the extent of surgical resection, and postoperative outcomes, were retrospectively evaluated. A new classification system was designed based on the anatomical–radiological findings and was evaluated in terms of clinical symptomatology, radiological features, surgical approach, and postoperative outcomes. Results The patient population comprised 22 women (57.9%) and 16 men (42.1%), with a mean age of 34.9 years. A practical classification system based on the radiological–anatomical vertical (1, 2, and 3) and horizontal (a, b, and c) tumor extensions was designed. No significant differences were found in the patients in terms of sex/age. The most commonly observed symptom was gait disturbance (34.2%). The preoperative tumor diameter was significantly larger in the subtotal resection (STR) group than in the gross total resection (GTR) and near-total resection (NTR) groups. Significantly more cistern involvement was observed in the STR group than in the GTR group. The GTR, NTR, and STR rates were higher in grade 1, 3, and 2 cases, respectively. The subgroup ‘a’ was correlated with higher resection rates (GTR and NTR), whereas the subgroup ‘b’ was correlated with STR. Conclusions Our suggested classification system represents a simple and practical model that may guide neurosurgeons in predicting the goal of resection during surgical planning and in minimizing potential morbidity.

Factors Associated With Abducens Nerve Palsy in Patients Undergoing Surgery for Petroclival Meningiomas.

During the surgical resection of petroclival meningiomas, preserving the cranial nerves is crucial. The abducens nerve is particularly vulnerable during surgery. However, the preoperative risk factors and postoperative prognosis of abducens nerve palsy (ANP) are poorly understood. We retrospectively analyzed 70 patients who underwent surgery for petroclival meningiomas between May 2010 and December 2019, divided into gross-total resection (GTR) and subtotal resection (STR) groups. The relationship of preoperative clinical factors with the incidence and recovery of postoperative ANP was analyzed. Postoperative ANP was observed in 23 patients (32.9%). Multivariable logistic regression revealed that the tumor-to-cerebellar peduncle T2 imaging intensity index (TCTI) (P < 0.001) and internal auditory canal invasion (P = 0.033) contributed to postoperative ANP. GTR was achieved in 37 patients (52.9%), and 10 (27.0%) of them showed ANP. STR was achieved in 33 patients (47.1%), and 13 (39.4%) of them showed ANP. Recovery from ANP took a median of 6.6 months (range, 4.5-20.3 months). At 6 months after the operation, recovery of the abducens nerve function was observed in 16 patients (69.0%); of whom, 4 (40.0%) were in the GTR group and 12 (92.3%) were in the STR group (P = 0.025). TCTI and internal auditory canal invasion were the risk factors for postoperative ANP. Although intentional STR did not prevent ANP immediately after the operation, recovery of the abducens nerve function after surgery was observed more frequently in the STR group than in the GTR group.

Multivariate Analysis and Validation of the Prognostic Factors for Skull Base Chordoma.

Background: Skull base chordoma is a rare tumor with low-grade malignancy and a high recurrence rate, the factors affecting the prognosis of patients need to be further studied. For that, we investigated prognostic factors of skull base chordoma through the database of the Surveillance, Epidemiology, and End Results (SEER) program, and validated in an independent data set from the Xiangya Hospital.Methods: Six hundred and forty-three patients diagnosed with skull base chordoma were obtained from the SEER database (606 patients) and the Xiangya Hospital (37 patients). Categorical variables were selected by Chi-square test with a statistical difference. Survival curves were constructed by Kaplan–Meier analysis and compared by log-rank test. Univariate and multivariate Cox regression analyses were used to explore the prognostic factors. Propensity score matching (PSM) analysis was undertaken to reduce the substantial bias between gross total resection (GTR) and subtotal resection (STR) groups. Furthermore, clinical data of 37 patients from the Xiangya Hospital were used as validation cohorts to check the survival impacts of the extent of resection and adjuvant radiotherapy on prognosis.Results: We found that age at diagnosis, primary site, disease stage, surgical treatment, and tumor size was significantly associated with the prognosis of skull base chordoma. PSM analysis revealed that there was no significant difference in the OS between GTR and STR (p = 0.157). Independent data set from the Xiangya Hospital proved no statistical difference in OS between GTR and STR groups (p = 0.16), but the GTR group was superior to the STR group for progression-free survival (PFS) (p = 0.048). Postoperative radiotherapy does not improve OS (p = 0.28), but it can prolong PFS (p = 0.0037). Nomograms predicting 5- and 10-year OS and DSS were constructed based on statistically significant factors identified by multivariate Cox analysis. Age, primary site, tumor size, surgical treatment, and disease stage were included as prognostic predictors in the nomograms with good performance.Conclusions: We identified age, tumor size, surgery, primary site, and tumor stage as main factors affecting the prognosis of the skull base chordoma. Resection of the tumor as much as possible while ensuring safety, combined with postoperative radiotherapy may be the optimum treatment for skull base chordoma.

Risk Factors for Anorectal Dysfunction After Interspincteric Resection in Patients With Low Rectal Cancer.

Purpose: The objective of this study was to explore the risk factors for anorectal dysfunction after intersphincteric resection in patients with low rectal cancer.Methods: A total of 251 patients who underwent intersphincteric resection from July 2014 to June 2020 were included in this study, for which the Kirwan's grade, Wexner score, and anorectal manometric index were used to evaluate the anorectal function and other parameters including demographics, surgical features, and clinical and pathological characteristics. These parameters were analysed to explore the potential risk factors for anorectal function after intersphincteric resection.Results: In the 251 included patients, 98 patients underwent partial intersphincteric resection, 87 patients underwent subtotal intersphincteric resection, and 66 patients underwent total intersphincteric resection. There were 53 (21.1%) patients who had postoperative complications, while no significant difference was observed between the three groups. Furthermore, 30 patients (45.5%) in the total intersphincteric resection group were classified as having anorectal dysfunction (Kirwan's grade 3–5), which was significantly higher than that in the partial intersphincteric resection group (27.6%) and subtotal intersphincteric resection group (29.9%). The mean Wexner score of patients that underwent total intersphincteric resection was 7.9, which was higher than that of patients that had partial intersphincteric resection (5.9, p = 0.002) and subtotal intersphincteric resection (6.4, p = 0.027). The initial perceived volume was lower in the total intersphincteric resection group than in the partial and subtotal intersphincteric resection groups at 1, 3, and 6 months after intersphincteric resection. In addition, the resting pressure, maximum squeeze pressure, and maximum tolerated volume in the total intersphincteric resection group were worse than those in the partial and subtotal groups at 3 and 6 months after intersphincteric resection. Univariate and multivariate analyses suggested that an age ≥65, total intersphincteric resection, and preoperative chemoradiotherapy were independent risk factors for anorectal dysfunction (P = 0.023, P = 0.003, and P = 0.008, respectively). Among the 66 patients who underwent total intersphincteric resection, 17 patients received preoperative chemoradiotherapy, of which 12 patients (70.6%) were classified as having anorectal dysfunction.Conclusion: The current study concluded that age ≥65, total intersphincteric resection, and preoperative chemoradiotherapy were risk factors for anorectal dysfunction after intersphincteric resection. The morbidity of anorectal dysfunction after total intersphincteric resection for patients who received preoperative chemoradiotherapy was relatively high, and the indication should be carefully evaluated.

Importance of Sufficient Petrosectomy in an Anterior Petrosal Approach: Relightening of the Kawase Pyramid

In 1985, Kawase published an anterior petrosal approach to expose the posterior cranial fossa and to minimize retraction of the temporal lobe. However, some neurosurgeons still have difficulty with removing tumors through an anterior petrosal approach because a complete understanding of the Kawase pyramid has not been achieved. We hypothesized that if anterior petrosectomy were performed with three-dimensional understanding of the Kawase pyramid, it would have a positive effect on extent of tumor resection. We performed a retrospective study of patients who underwent surgical treatment for meningioma through an anterior petrosal approach. Patients were divided into total resection and subtotal resection groups, and statistical differences between the groups were analyzed. To identify factors predictive of complete tumor removal, univariable and multivariable logistic regression analyses were performed. Width and height of the drilled internal auditory canal of the total resection group were significantly larger than those of the subtotal resection group (P= 0.001, P= 0.033). The operative angle of the total resection group was significantly larger than that of the subtotal resection group (P < 0.001). Regression analyses showed only drilled internal auditory canal width to be predictive of complete tumor removal, increasing the likelihood of complete tumor removal by 2.778-fold with an increase in drilled internal auditory canal width by 1 mm (P= 0.023). Insufficient petrosectomy during an anterior petrosal approach adversely affects the extent of tumor resection. Furthering three-dimensional understanding of the Kawase pyramid could aid in complete tumor resection and better outcomes without causing damage to the surrounding organs.