A novel MAPT variant (E342K) as a cause of familial progressive supranuclear palsy.

Background: MAPT variants are a known cause of frontotemporal dementia and Parkinsonian syndrome, of which progressive supranuclear palsy syndrome (PSP) is a rare manifestation. Objective: To report a novel MAPT variant in a PSP pedigree with autosomal dominant inheritance pattern, and to produce a literature review of PSP patients with MAPT variants. Methods: A comprehensive clinical, genetic, and molecular neuroimaging investigation was conducted on a 61 years-old female proband diagnosed with PSP. We also collected the clinical presentation data and history of the patient's pedigree, and performed further genetic analysis of 4 relatives, from two generations, with and without symptoms. Results: The proband exhibited typical clinical manifestation of PSP. A cranial MRI revealed midbrain atrophy, and an FDG-PET scan suggested hypo-metabolic changes in caudate nucleus, left prefrontal lobe, both temporal poles, and midbrain. 18F-florzolo-tau-PET revealed tau-protein deposits in the thalamus and brainstem bilaterally. A gene test by whole-exome sequencing identified a novel MAPT variant [NM_005910.6, exon 11, c.1024G > A (p.E342K)], and the same variant was also identified in one affected relative and one asymptomatic relative, a probable pre-symptomatic carrier. Conclusion: The PSP pedigree caused by the novel MAPT (E342K) variant, expanded the mutational spectrum of MAPT.

Dominance of Tau Burden in Cortical Over Subcortical Regions Mediates Glymphatic Activity and Clinical Severity in PSP.

BACKGROUND: Progressive supranuclear palsy (PSP) is a tauopathy that involves subcortical regions but also extends to cortical areas. The clinical impact of different tau protein sites and their influence on glymphatic dysfunction have not been investigated. PATIENTS AND METHODS: Participants (n = 55; 65.6 ± 7.1 years; 29 women) with PSP (n = 32) and age-matched normal controls (NCs; n = 23) underwent 18 F-Florzolotau tau PET, MRI, PSP Rating Scale (PSPRS), and Mini-Mental State Examination. Cerebellar gray matter (GM) and parametric estimation of reference signal intensity were used as references for tau burden measured by SUV ratios. Glymphatic activity was measured by diffusion tensor image analysis along the perivascular space (DTI-ALPS). RESULTS: Parametric estimation of reference signal intensity is a better reference than cerebellar GM to distinguish tau burden between PSP and NCs. PSP patients showed higher cortical and subcortical tau SUV ratios than NCs ( P < 0.001 and <0.001). Cortical and subcortical tau deposition correlated with PSPRS, UPDRS, and Mini-Mental State Examination scores (all P 's < 0.05). Cortical tau deposition was further associated with the DTI-ALPS index and frontal-temporal-parietal GM atrophy. The DTI-ALPS indexes showed a significantly negative correlation with the PSPRS total scores ( P < 0.01). Finally, parietal and occipital lobe tau depositions showed mediating effects between the DTI-ALPS index and PSPRS score. CONCLUSIONS: Cortical tau deposition is associated with glymphatic dysfunction and plays a role in mediating glymphatic dysfunction and clinical severity. Our results provide a possible explanation for the worsening of clinical severity in patients with PSP.

Hyperpolarized [1-13C]-pyruvate MRS evaluates immune potential and predicts response to radiotherapy in cervical cancer.

BACKGROUND: Monitoring pyruvate metabolism in the spleen is important for assessing immune activity and achieving successful radiotherapy for cervical cancer due to the significance of the abscopal effect. We aimed to explore the feasibility of utilizing hyperpolarized (HP) [1-13C]-pyruvate magnetic resonance imaging (MRI) and magnetic resonance spectroscopy (MRS) to evaluate pyruvate metabolism in the human spleen, with the aim of identifying potential candidates for radiotherapy in cervical cancer. METHODS: This prospective study recruited six female patients with cervical cancer (median age 55 years; range 39-60) evaluated using HP [1-13C]-pyruvate MRI/MRS at baseline and 2 weeks after radiotherapy. Proton (1H) diffusion-weighted MRI was performed in parallel to estimate splenic cellularity. The primary outcome was defined as tumor response to radiotherapy. The Student t-test was used for comparing 13C data between the groups. RESULTS: The splenic HP [1-13C]-lactate-to-total carbon (tC) ratio was 5.6-fold lower in the responders than in the non-responders at baseline (p = 0.009). The splenic [1-13C]-lactate-to-tC ratio revealed a 1.7-fold increase (p = 0.415) and the splenic [1-13C]-alanine-to-tC ratio revealed a 1.8-fold increase after radiotherapy (p = 0.482). The blood leukocyte differential count revealed an increased proportion of neutrophils two weeks following treatment, indicating enhanced immune activity (p = 0.013). The splenic apparent diffusion coefficient values between the groups were not significantly different. CONCLUSIONS: This exploratory study revealed the feasibility of HP [1-13C]-pyruvate MRS of the spleen for evaluating baseline immune potential, which was associated with clinical outcomes of cervical cancer after radiotherapy. TRIAL REGISTRATION: ClinicalTrials.gov NCT04951921 , registered 7 July 2021. RELEVANCE STATEMENT: This prospective study revealed the feasibility of using HP 13C MRI/MRS for assessing pyruvate metabolism of the spleen to evaluate the patients' immune potential that is associated with radiotherapeutic clinical outcomes in cervical cancer. KEY POINTS: • Effective radiotherapy induces abscopal effect via altering immune metabolism. • Hyperpolarized 13C MRS evaluates patients' immune potential non-invasively. • Pyruvate-to-lactate conversion in the spleen is elevated following radiotherapy.

Should sub-millimeter margins be deemed positive in oral cavity squamous cell carcinoma?

BACKGROUND: While several studies have indicated that a margin status of < 1 mm should be classified as a positive margin in oral cavity squamous cell carcinoma (OCSCC), there is a lack of extensive cohort studies comparing the clinical outcomes between patients with positive margins and margins < 1 mm. METHODS: Between 2011 and 2020, we identified 18,416 Taiwanese OCSCC patients who underwent tumor resection and neck dissection. Of these, 311 had margins < 1 mm and 1013 had positive margins. To compare patients with margins < 1 mm and those with positive margins, a propensity score (PS)-matched analysis (n = 253 in each group) was conducted. RESULTS: The group with margins < 1 mm displayed a notably higher prevalence of several variables: 1) tongue subsite, 2) younger age, 3) smaller depth of invasion), 4) early tumor stage, and 5) treatment with surgery alone. Patients with margins < 1 mm demonstrated significantly better disease-specific survival (DSS) and overall survival (OS) rates compared to those with positive margins (74 % versus 53 %, 65 % versus 43 %, both p < 0.0001). Multivariable analysis further confirmed that positive margins were an independent predictor of worse 5-year DSS (hazard ratio [HR] = 1.38, p = 0.0103) and OS (HR = 1.28, p = 0.0222). In the PS-matched cohort, the 5-year outcomes for patients with margins < 1 mm compared to positive margins were as follows: DSS, 71 % versus 59 %, respectively (p = 0.0127) and OS, 60 % versus 48 %, respectively (p = 0.0398). CONCLUSIONS: OCSCC patients with a margin status < 1 mm exhibited distinct clinicopathological characteristics and a more favorable prognosis compared to those with positive resection margins.

Comparing the clinical outcomes of initial surgery and primary definitive radiotherapy with a dosage of 6600 cGy or higher in cT1-2N0M0 oral cavity squamous cell carcinoma: A nationwide cohort study.

BACKGROUND: To compare the clinical outcomes of two treatment modalities, initial surgery and primary definitive radiotherapy (RT), in Taiwanese patients diagnosed with cT1-2N0M0 oral cavity squamous cell carcinoma (OCSCC). METHODS: Between 2011 and 2019, we analyzed data for 13,542 cT1-2N0M0 patients who underwent initial surgery (n = 13,542) or definitive RT with a dosage of at least 6600 cGy (n = 145) for the treatment of OCSCC. To account for baseline differences, we employed propensity score (PS) matching, resulting in two well-balanced study groups (initial surgery, n = 580; definitive RT, n = 145). RESULTS: Before PS matching, the 5-year disease-specific survival (DSS) rates were 88% for the surgery group and 58% for the RT group. After PS matching, the 5-year DSS rates of the two groups were 86% and 58%, respectively. Similarly, the 5-year overall survival (OS) rates before PS matching were 80% for the surgery group and 36% for the RT group, whereas after PS matching, they were 73% and 36%, respectively. All these differences were statistically significant (p < 0.0001). A multivariable analysis identified treatment with RT, older age, stage II tumors, and a higher burden of comorbidities as independent risk factors for both DSS and OS. We also examined the 5-year outcomes for various subgroups (margin ≥5 mm, margin <5 mm, positive margins, RT combined with chemotherapy, and RT alone) as follows: DSS, 89%/88%/79%/63%/51%, respectively, p < 0.0001; OS, 82%/79%/68%/39%/32%, respectively, p < 0.0001. CONCLUSIONS: In Taiwanese patients with cT1-2N0M0 OCSCC, a remarkably low proportion (1.1%) completed definitive RT. A significant survival disparity of 30% was observed between patients who underwent initial surgery and those who received definitive RT. Interestingly, even patients from the surgical group with positive surgical margins exhibited a significantly superior survival compared to those in the definitive RT group.

Prognostic impact of elective tracheotomy in resected oral cavity squamous cell carcinoma: A nationwide cohort study.

BACKGROUND: Elective tracheotomy is commonly performed in resected oral squamous cell carcinoma (OCSCC) to maintain airway patency. However, the indications for this procedure vary among surgeons. This nationwide study evaluated the impact of tracheotomy on both the duration of in-hospital stay and long-term survival outcomes in patients with OCSCC. METHODS: A total of 18,416 patients with OCSCC were included in the analysis, comprising 7981 patients who underwent elective tracheotomy and 10,435 who did not. The primary outcomes assessed were 5-year disease-specific survival (DSS) and overall survival (OS). To minimize potential confounding factors, a propensity score (PS)-matched analysis was performed on 4301 patients from each group. The duration of hospital stay was not included as a variable in the PS-matched analysis. RESULTS: Prior to PS matching, patients with tracheotomy had significantly lower 5-year DSS and OS rates compared to those without (71% vs. 82%, p < 0.0001; 62% vs. 75%, p < 0.0001, respectively). Multivariable analysis identified tracheotomy as an independent adverse prognostic factor for 5-year DSS (hazard ratio = 1.10 [1.03-1.18], p = 0.0063) and OS (hazard ratio = 1.10 [1.04-1.17], p = 0.0015). In the PS-matched cohort, the 5-year DSS was 75% for patients with tracheotomy and 76% for those without (p = 0.1488). Five-year OS rates were 66% and 67%, respectively (p = 0.0808). Prior to PS matching, patients with tracheotomy had a significantly longer mean hospital stay compared to those without (23.37 ± 10.56 days vs. 14.19 ± 8.34 days; p < 0.0001). Following PS matching, the difference in hospital stay duration between the two groups remained significant (22.34 ± 10.25 days vs. 17.59 ± 9.54 days; p < 0.0001). CONCLUSIONS: While elective tracheotomy in resected OCSCC patients may not significantly affect survival, it could be associated with prolonged hospital stays.

Prognostic impact of bridge or neoadjuvant induction chemotherapy in patients with resected oral cavity cancer: A nationwide cohort study.

BACKGROUND: While surgery remains the primary treatment for oral squamous cell carcinoma (OCSCC), induction chemotherapy (IC) can be used as a bridging or neoadjuvant therapy. This nationwide study in Taiwan examines the survival outcomes of OCSCC patients who received IC before surgery. METHODS: We analyzed data from 29,891 patients with OCSCC. Of these, 29,058 initially underwent surgery (OP group), whereas 833 received IC before surgery (IC + OP group). A propensity score (PS)-matched analysis (4, 1 ratio, 3260 vs. 815 patients) was performed considering tumor subsite, sex, age, Charlson comorbidity index, clinical T1-T4b tumors, clinical N0-3 disease, and clinical stage I-IV. RESULTS: In the PS-matched cohort, the 5-year disease-specific survival (DSS) and overall survival (OS) rates were 65% and 57%, respectively. When comparing the OP and IC + OP groups, the 5-year DSS rates were 66% and 62%, respectively (p = 0.1162). Additionally, the 5-year OS rates were 57% and 56%, respectively (p = 0.9917). No significant intergroup differences in survival were observed for specific subgroups with cT4a tumors, cT4b tumors, cN3 disease, pT4b tumors, and pN3 disease. However, for patients with pT4a tumors, the OP group demonstrated superior 5-year outcomes compared to the IC + OP group, with a DSS of 62% versus 52% (p = 0.0006) and an OS of 53% versus 44% (p = 0.0060). Notably, patients with cT2-3, cN1, and c-Stage II disease in the IC + OP group were significantly more likely to achieve pT0-1 status (p < 0.05). CONCLUSIONS: Following PS matching, the IC + OP group generally exhibited similar prognosis to the OP group. However, for pT4a tumors, the OP group showed superior 5-year outcomes. While IC may not universally improve survival, it could be advantageous for patients who respond positively to the treatment.

Is elective neck dissection justified in cT2N0M0 oral cavity cancer defined according to the AJCC eighth edition staging system?

BACKGROUND: The current NCCN guidelines recommend considering elective neck dissection (END) for early-stage oral cavity squamous cell carcinoma (OCSCC) with a depth of invasion (DOI) exceeding 3 mm. However, this DOI threshold, determined by evaluating the occult lymph node metastatic rate, lacks robust supporting evidence regarding its impact on patient outcomes. In this nationwide study, we sought to explore the specific indications for END in patients diagnosed with OCSCC at stage cT2N0M0, as defined by the AJCC Eighth Edition staging criteria. METHODS: We examined 4723 patients with cT2N0M0 OCSCC, of which 3744 underwent END and 979 were monitored through neck observation (NO). RESULTS: Patients who underwent END had better 5-year outcomes compared to those in the NO group. The END group had higher rates of neck control (95% vs. 84%, p < 0.0001), disease-specific survival (DSS; 87% vs. 84%, p = 0.0259), and overall survival (OS; 79% vs. 73%, p = 0.0002). Multivariable analysis identified NO, DOI ≥5.0 mm, and moderate-to-poor tumor differentiation as independent risk factors for 5-year neck control, DSS, and OS. Based on these prognostic variables, three distinct outcome subgroups were identified within the NO group. These included a low-risk subgroup (DOI <5 mm plus well-differentiated tumor), an intermediate-risk subgroup (DOI ≥5.0 mm or moderately differentiated tumor), and a high-risk subgroup (poorly differentiated tumor or DOI ≥5.0 mm plus moderately differentiated tumor). Notably, the 5-year survival outcomes (neck control/DSS/OS) for the low-risk subgroup within the NO group (97%/95%/85%, n = 251) were not inferior to those of the END group (95%/87%/79%). CONCLUSIONS: By implementing risk stratification within the NO group, we found that 26% (251/979) of low-risk patients achieved outcomes similar to those in the END group. Therefore, when making decisions regarding the implementation of END in patients with cT2N0M0 OCSCC, factors such as DOI and tumor differentiation should be taken into account.