Hongchuan Guo

Resection of Anterior Cranial Base Meningiomas with Intra- and Extracranial Involvement via a Purely Endoscopic Endonasal Approach

Objective: The complete resection of anterior cranial base meningiomas with intra- and extracranial involvement is always challenging. We describe our experience of treating such meningiomas via a purely endoscopic endonasal approach (EEA). Methods: Eight patients with intra- and extradural meningiomas were operated via EEA. In this study, we describe the operative technique, and analyze the degree of resection, complications and the clinical outcomes. Results: The complete resection of meningiomas with intra- and extracranial involvement was achieved in all patients using EEA. Preoperative visual symptoms were improved or resolved in all cases. One patient experienced a postoperative cerebrospinal fluid leak and delayed meningitis. No patient in our series experienced a new neurological deficit after surgery or recurrence in the follow-up period (18–60 months). Conclusion: Our limited experience indicates that EEA is feasible and safe for the complete resection of anterior cranial base meningiomas with intra- and extracranial involvement in one stage in selected cases.

The PI3K inhibitor GDC-0941 enhances radiosensitization and reduces chemoresistance to temozolomide in GBM cell lines.

Glioblastoma multiforme (GBM) is among the most lethal of all human tumors. It is the most frequently occurring malignant primary brain tumor in adults. The current standard of care (SOC) for GBM is initial surgical resection followed by treatment with a combination of temozolomide (TMZ) and ionizing radiation (IR). However, GBM has a dismal prognosis, and survivors have compromised quality of life owing to the adverse effects of radiation. GBM is characterized by overt activity of the phosphoinositide 3-kinase (PI3K) signaling pathway. GDC-0941 is a highly specific PI3K inhibitor with promising anti-tumor activity in human solid tumors. It is being evaluated in Phase II clinical trials for the treatment of breast and non-squamous cell lung cancer. We hypothesized that GDC-0941 may act as an antitumor agent and potentiate the effects of TMZ and IR. In this study, GDC-0941 alone induced cytotoxicity and pro-apoptotic effects. Moreover, combined with the standard GBM therapy (TMZ and IR), it suppressed cell viability, showed enhanced pro-apoptotic effects, augmented autophagy response, and attenuated migratory/invasive capacity in three glioma cell lines. Protein microarray analyses showed that treatment with TMZ+GDC-0941+IR induced higher levels of p53 and glycogen synthase kinase 3-beta (GSK3-β) expression in SHG44GBM cells than those induced by other treatments. This was verified in all cell lines by western blot analysis. Furthermore, the combination of TMZ and GDC-0941 with or without IR reduced the levels of p-AKT and O6-methylguanine DNA methyltransferase (MGMT) in T98G cells. The results of this study suggest that the combination of TMZ, IR, and GDC-0941 is a promising choice for future treatments of GBM.

Identification of cranial nerves around trigeminal schwannomas using diffusion tensor tractography: a technical note and report of 3 cases

BackgroundThere are no large series studies identifying the locations of cranial nerves (CNs) around trigeminal schwannomas (TSs); however, surgically induced cranial neuropathies are commonly observed after surgeries to remove TSs. In this study, we preoperatively identified the location of CNs near TSs using diffusion tensor tractography (DTT).MethodsAn observational study of the DTT results and intraoperative findings was performed. We preoperatively completed tractography from images of patients with TSs who received surgical therapy. The result was later validated during tumorectomy.ResultsA total of three consecutive patients were involved in this study. The locations of CNs V-VIII in relation to the tumor was clearly revealed in all cases, except for CN VI in case 3.The predicted fiber tracts were in agreement with intraoperative observations.ConclusionsIn this study, preoperative DTT accurately predicted the location of the majority of the nerves of interest. This technique can be applied by surgeons to preoperatively visualize nerve arrangements.

Endoscopic endonasal removal of pituitary adenomas with paraclival internal carotid artery invasion.

Objective: To retrospectively evaluate the effectiveness of the endoscopic endonasal removal of pituitary adenomas (PAs) with paraclival internal carotid artery (ICA) invasion. Methods: Between February 2002 and August 2009, 14 consecutive patients underwent ‘pure’ extended endonasal transsphenoidal endoscopic surgery for PAs with paraclival ICA invasion. The clinical outcomes of the patients were evaluated, including symptoms, the extent of the tumor, the amount of tumor removed and any complications. Results: Tumor removal, as assessed by intraoperative endoscopic inspection, postoperative magnetic resonance imaging and clinical evaluation, revealed total resection (cured) in 10 out of 14 PA patients, 1 subtotal resection (controlled), and 3 partial resections (improved). Three patients had recurrences and 2 underwent re-resection. A cerebrospinal fluid leak was seen in 1 patient. There were no cases of meningitis. All of the patients who had symptoms were discharged. Conclusion: Extended endonasal transsphenoidal endoscopic surgery for PAs with paraclival ICA invasion is a safe and effective alternative procedure after proper training. Moreover, the technique is less invasive and effective and requires less time than traditionally utilized procedures.

Trigeminal Neuralgia Secondary to Osteoid Osteoma of the Petrous Bone: Report of 4 Cases and Brief Review of Literature

OBJECTIVE To retrospectively analyze clinical data of 4 patients with trigeminal neuralgia (TN) secondary to osteoid osteoma (OO) of the petrous bone and discuss treatment for this rare disease. METHODS Between January 2008 and December 2016, 4 patients in whom TN secondary to petrous bone OO was diagnosed received surgical treatment in Xuan Wu Hospital of Capital Medical University. We summarized the characteristics and treatments of this rare disease through retrospective review of the clinical information, imaging features, surgical details, and follow-up outcomes of the 4 patients. RESULTS Among the 4 patients, 2 were men; mean age was 39.3 ± 12.3 years (range, 26-52 years). All patients presented with symptoms of typical TN. Preoperative bone window computed tomography scan of the brain showed a regular bony lesion located at the petrous bone, contacting the trigeminal nerve. All patients experienced total relief of symptoms after surgical resection of the lesion by retrosigmoid sinus approach. During a mean follow-up of 14.2 months (range, 7-23 months), no preoperative symptoms recurred. CONCLUSIONS TN secondary to petrous bone OO is extremely uncommon. Surgical decompression is an effective treatment for patients with petrous bone OO and associated TN.

Circulating and tumor‑infiltrating myeloid‑derived suppressor cells in cervical carcinoma patients

Myeloid-derived suppressor cells (MDSCs) serve an immunosuppressive role in human tumors. Human Lin-/low human leukocyte antigen-antigen D related (HLA-DR-) cluster of differentiation (CD)-11b+CD33+ MDSCs are closely linked with tumor staging, progression, clinical therapeutic efficacy and prognosis for various types of tumors. The present study employed multiparametric flow cytometry to measure the proportion of Lin-/lowHLA-DR-CD11b+CD33+ MDSCs in the peripheral blood of 105 cervical cancer patients and 50 healthy subjects. The level of MDSC was higher in tumor patients than in the normal control group and this was closely associated with clinical staging. Further analysis of tumor-infiltrating MDSCs was performed in 22 patients. The MDSC proportions in tumor tissue were significantly higher than those in the corresponding adjacent tissue. The phenotypic characteristics of Lin-/lowHLA-DR-CD11b+CD33+ MDSCs were then evaluated and the results revealed that they express high CD13 and CD39, and low CD115, CD117, CD124 and programmed cell death ligand 1; they were also devoid of CD14, CD15 and CD66b. MDSCs and T-cells from peripheral blood were sorted by flow cytometry for co-culture experiments. Lin-/lowHLA-DR-CD11b+CD33+ MDSCs from patients significantly inhibited the proliferation of CD4 and CD8 T-cells. Furthermore, functional analysis verified that MDSCs from cervical cancer patients could inhibit interleukin-2 and interferon-γ production from T-cells. In addition, the associations between peripheral circulating MDSCs and tumor infiltrating MDSCs, and tumor relapse and metastasis were analyzed. The number of peripheral MDSCs and MDSCs in tumor tissue were observed to be associated with relapse-free survival. Thus, MDSCs in the peripheral blood and tumors of cervical cancer patients have a significant immunosuppressive effect, and are associated with cervical cancer staging and metastasis. These results suggest that targeting MDSCs may increase antitumor immunity and increase the efficacy of cervical cancer therapies.

Surgical treatment of trigeminal neuralgia with no neurovascular compression: A retrospective study and literature review

The objective of the current study is to summarize the experiences of 360-degree circumferential arachnoid dissection for TN in patients without NVC. Clinical data from 19 TN patients without NVC who underwent 360-degree circumferential arachnoid dissection were retrospectively analyzed. All patients underwent preoperative examinations of three-dimensional time-of-flight magnetic resonance angiography (3D-TOF-MRA) and three-dimensional nuclear magnetic resonance of constructive interference in steady state (3D-CISS) to identify the neurovascular structures around the trigeminal nerve. Surgical outcomes were evaluated based on the Barrow Neurological Institute (BNI) Pain Intensity Scale, and severity of pain was determined using the visual analogue scale (VAS) score. Preoperative imaging showed that no patients had NVC compression. The preoperative BNI pain score was IV among 9 patients and V among other 10 patients. The preoperative VAS score was 7.89 ± 0.658. After the operation, pain disappeared in all 19 patients, and transient facial numbness occurred in 3 patients. During follow-up, pain in 2 of 19 patients (10.5%) recurred at postoperative 20 and 23 months. This study demonstrated that 360-degree circumferential arachnoid dissection is an alternative treatment for trigeminal neuralgia in patients with no neurovascular compression, especially when a thickened arachnoid, angulation, or torsion of the trigeminal nerve root was found during the operation. However, further study is needed to compare the outcomes of different surgical strategies and prove the efficacy of 360-degree circumferential arachnoid dissection in cases without neurovascular compression (NVC).

Endoscopic Approach to Remove Intra-extracranial Tumors in Various Skull Base Regions: 10-year Experience of a Single Center

Background: Some problems have been found in the usually adopted combined approach for the removal of intra-extracranial tumors in skull base. Herein, we described a pure endoscopic transnasal or transoral approach (ETA) for the removal of intra-extracranial tumors in various skull base regions. Methods: Retrospectively, clinical data, major surgical complications, pre- and postoperative images, and follow-up information of a series of 85 patients with intra-extracranial tumors in various skull base regions who were treated by surgery via ETA in our skull base center during the past 10 years were reviewed and analyzed. Results: Gross total tumor removal was achieved in 80/85 cases (94.1%) in this study. All 37 cases with tumors in anterior skull base and all 14 cases with tumors in jugular foramen received total tumor removal. Thirteen and three cases with tumors in clivus received total and subtotal tumor removal, respectively. Total and subtotal tumor removal was performed for 16 cases and 2 cases in lateral skull base, respectively. The complications in this study included: cerebrospinal fluid leakage (n = 3), meningitis (n = 3), and new cranial nerve deficits (n = 3; recovered in 3 months after surgery). In the follow-up period of 40–151 months (median: 77 months), seven patients (8.8%) out of the 80 cases of total tumor removal experienced recurrence. Conclusions: Complete resection of intra-extracranial growing tumors in various skull base regions can be achieved via the pure ETA in one stage in selected cases. Surgical procedure for radical removal of tumors is feasible and safe.

Endoscopic transoral approach for extracranial hypoglossal schwannoma.

Objective: Hypoglossal nerve schwannoma, especially when inside the extracranial region, is extremely rare. This report describes a new endoscopic transoral approach for the removal of extracranial hypoglossal schwannoma. Patients and Methods: Three patients (1 male and 2 females, aged 58–63 years) with extracranial hypoglossal schwannoma in the paroccipital condyle and the jugular foramen were treated solely by an endoscopic transoral approach. All patients presented signs of hypoglossal nerve paresis with hemiatrophy of the tongue. In addition, one of them had glossopharyngeal nerve paresis, and vagus nerve paresis was found in another patient. Results: In all patients, tumors underwent successful radical intracapsular removal by the endoscopic transoral approach, as confirmed by the postoperative examinations and MRI. No complications occurred during or after surgery, except that 1 patient had swallowing difficulties and a temporary right vagus palsy during the first day after surgery. All patients were followed up for 6 months, and the lack of any recurrence has been confirmed. Muscle bulk, motor and swallowing functions, and the vagus palsy improved in all patients. Conclusion: The endoscopic transoral approach is a safe and useful surgical technique for the removal of intracapsular tumors, including extracranial hypoglossal schwannomas, which involves minimal invasion.