[Anatomical classification and application of chimeric myocutaneous medial thigh perforator flap in head and neck reconstruction]

Objective: To explore the anatomical classification and application of chimeric myocutaneous medial thigh perforator (MTP) flap in head and neck reconstruction. Methods: From September 2015 to December 2018, the clinical data of 74 patients (62 males and 12 females, age ranging from 31 to 69 years, with a mean age of 50.2 years) with oral tumor, who underwent radical resection in Hunan Cancer Hospital, including 39 cases of tongue carcinoma, 24 cases of gingival carcinoma and 11 cases of buccal cancer, 26 cases of stage T4N1M0, 22 cases of stage T4N0M0,15 cases of stage T3N1M0, and 11 cases of stage T3N2M0 were retrospectively analyzed in this work.The arteries and the veins contributing to MTP were anastomosed respectively with superior thyroid arteries, while the venae comitans were anastomosed with superior thyroid venae veins or internal jugular venae vein. The size of soft tissue defect, the length, width and thickness of free medial thigh flap, the length and source of vascular pedicle were recorded. The flap survival, functional status and donor area recovery were observed. Results: The postoperative defects in size ranged from 4.0 cm×3.5 cm to 9.0 cm×5.5 cm, which were reconstructed by free chimeric myocutaneous MTP flaps. The mean length of MTP flaps was (12.5±0.4) cm, the mean width was (7.2±0.4) cm, the mean thickness was (3.5±0.2) cm. The mean pedicle length was (8.6±0.4) cm. The perforators existed consistently in all cases, and the vascular origins were classified into 6 types. There were 4 cases (5.4%) of the perforating branches originating from femoral artery between the medial femoris and the adductor longus, 6 cases (8.1%) of the perforating branches of the profunda femoral artery from the adductor longus, 16 cases (21.6%) of the perforating branches of the profunda femoral artery from the gracilis, 9 cases (12.2%) of the perforating branches of the profunda femoral artery between the gracilis and the adductor longus, 29 cases (39.2%) of the perforating branches of the profunda femoral artery from the adductor longus, and 10 cases (13.5%) of branches of the profunda femoral artery from the semimembranous muscle. All 74 flaps survived uneventfully. The donor sites and recipient sites were closed directly in all cases. All patients were followed up for 12-36 months with satisfied esthetic and functional results. Only linear scars were left in the donor sites, and the thigh function was not affected. Local recurrence happened in 4 cases, which were treated with radical resection and the left defects were reconstructed with pedicled pectoral major myocutaneous flaps. Conclusion: The chimeric myocutaneous MTP flap has good color match and texture, with abundant tissue, and consistent blood supply, and it can be harvested in various forms while leaving minimal morbidity at donor site, being an idea choice for reconstruction after surgery of oral cancer.

[Effects of pedicled rectus abdominis myocutaneous flap combined with free deep inferior epigastric artery perforator flap carrying inguinal lymphatic flap in breast reconstruction and upper limb lymphedema treatment post radical mastectomy]

Objective: To explore the effects of pedicled rectus abdominis myocutaneous (PRAM)flap combined with free deep inferior epigastric artery perforator (DIEAP) flap carrying inguinal lymphatic flap in breast reconstruction and upper limb lymphedema treatment post radical mastectomy. Methods: From October 2014 to September 2016, 9 patients with upper limb lymphedema after mastectomy were treated with PRAM flap combined with free DIEAP flap carrying inguinal lymphatic flap for breast reconstruction and upper limb lymphedema treatment in Hunan Province Cancer Hospital. The patients were all females, aged 34-66 (44±7) years. The location of deep inferior epigastric artery perforator was detected by audible Doppler ultrasound blood stream detector and computed tomography angiography for designing combined tissue flap, with length of (25.32±0.27) cm, width of (13.14±0.76) cm, and thickness of (3.55±0.34) cm. The donor site of combined tissue flap was closed by suturing, and two or more tubes for negative pressure drainage were placed according to the situation of donor site and recipient site. Operation time and average placing time of negative pressure drainage tube, postoperative condition of combined tissue flap and the donor site, reconstructed breast condition, recovery of upper limb lymphedema were documented and followed up. Results: The operation time was 290-420 (396±55) min. The average retaining time of negative pressure drainage tube in breast was 5.9 d, while the average retaining time of negative pressure drainage tube in abdomen was 4.3 d. Ecchymoma occurred in DIEAP flap of one patient and in the flap donor site of another patient. Delayed healing was also seen in the rectus abdominis myocutaneous flap of a patient, which healed eventually after dressing change, and the other flaps survived well. The appearance of reconstructed breast was good with good elasticity, and no contracture or deformation occurred in the tissue flap. The upper limb lymphedema in 7 patients was alleviated in varying degrees, with 2.0-4.0 cm reduction in circumference. During follow-up of 12-24 months of 9 patients, averaged 17.5 months, with 6 patients received long term bandage pressure therapy and physical therapy to the affected limbs after operation and all patients were satisfied with appearances of the affected limbs. Neuropathic pain in affected limbs was significantly relieved in 2 patients and stopped aggravating in the other 2 patients. Only linear scar was seen in the donor site of abdomen without affecting obviously the function of abdomen. Conclusions: The PRAM flap combined with free DIEAP flap carrying inguinal lymphatic flap is an effective way for breast reconstruction and upper limb lymphedema treatment post mastectomy.

[Research Progress of Immunotherapy and Prognostic Markers in Small Cell Lung Cancer]

近年来，虽然非小细胞肺癌患者的治疗效果得到了明显的改善，但小细胞肺癌（small cell lung cancer, SCLC）患者仍因治疗选择有限而预后很差。SCLC发病率占肺癌总体发病率的15%，具有恶性程度高、生长迅速、易发生远处转移及复发的特点，治疗十分棘手。随着免疫治疗获批于非小细胞肺癌等多种实体瘤，作为免疫源性相对较强的癌种，SCLC的相关临床研究也在开展中，并已取得一定的进展。另一方面，由于肿瘤异质性的存在，探索能够预测SCLC疗效的相关标志物对患者精准治疗至关重要。本综述阐述了目前SCLC免疫治疗及与SCLC免疫治疗相关生物标志物研究的最新进展。

Tumor microenvironment evaluation to predict pembrolizumab benefit of metastatic gastric cancer: Results from phase II clinical trial

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Background: Clinical studies support the efficacy of immune checkpoint blockades (ICBs) in a subset of patients with metastatic gastric cancer (mGC). With the aim of identifying determinants of response to ICBs, we performed molecular characterization of tissues from 61 patients with mGC who were treated with pembrolizumab as salvage treatment in a prospective phase 2 clinical trial (NCT#02589496). Methods: Of 61 patients, 60 patients underwent pretreatment biopsy and 45 specimens were of sufficiently high quality for RNA sequencing. TMEscore, which was previously established to quantify the tumor microenvironment (TME), was used to estimated TME of pretreatment specimens. The predictive value and correlation of integrative molecular characterization were systematically explored. Results: We established a methodology (TMEscore) to evaluated the TME of GC patients, which was previously found to be a robust prognostic and predictive biomarker for patients treated with ICBs. By applying ROC curve analysis, the TMEscore was found to be a best predictive biomarker (TMEscore: AUC = 0.891; CPS: AUC = 0.830; TMB: AUC = 0.672; MSI status: AUC = 0.708; EBV status: AUC = 0.727; respectively). Moreover, TMEscore was the most significant gene signature that correlated with tumor response (TMEscore: P = 1.7 × 10 −5; GEPs: P = 0.00035; ImmunoScore: P = 0.29106; CD8+ T cell fraction: P = 0.00011; Immune checkpoint score: P = 0.00149; respectively). TMB was not correlated with TMEscore (Kruskal-Wallis test, P = 0.14). A higher TMEscore was significantly associated with EBV+ and high-MSI TCGA molecular subtypes (Kruskal-Wallis test, P = 0.002) which were reported to benefit from ICBs of GC. Conclusions: These findings indicate that the assessment of TMEscore via high throughput-sequencing and PCA algorithm provides a robust biomarker for the selection of GC patients who may derive greater benefit from pembrolizumab. Our data also suggest that TMEscore may be a more accurate predictive biomarker than TMB, MSI and EBV status, and this resource may help facilitate the development of precision immunotherapy. Clinical trial information: NCT#02589496.

Nuclear Dependence of the Transverse Single-Spin Asymmetry in the Production of Charged Hadrons at Forward Rapidity in Polarized p+p, p+Al, and p+Au Collisions at sqrt[s_{NN}]=200 GeV

We report on the nuclear dependence of transverse single-spin asymmetries (TSSAs) in the production of positively charged hadrons in polarized p^{↑}+p, p^{↑}+Al, and p^{↑}+Au collisions at sqrt[s_{NN}]=200  GeV. The measurements have been performed at forward rapidity (1.4<η<2.4) over the range of transverse momentum (1.8<p_{T}<7.0  GeV/c) and Feynman x (0.1<x_{F}<0.2). We observed positive asymmetries for positively charged hadrons in p^{↑}+p collisions, and significantly reduced asymmetries in p^{↑}+A collisions. These results reveal a nuclear dependence of TSSAs for charged-hadron production in a regime where perturbative techniques are applicable. These results provide new opportunities to use p^{↑}+A collisions as a tool to investigate the rich phenomena behind TSSAs in hadronic collisions and to use TSSAs as a new handle in studying small-system collisions.

[The clinical applied analysis of the modified transoral endoscopic thyroidectomy vestibular approach]

Objective: To investigate the safety and feasibility of the modified transoral endoscopic thyroidectomy vestibular approach (TOETVA) by dissection of mental nerve in clinical practice. Methods: Totally 140 patients underwent the modified TOETVA from the Department of Head and Neck Surgery, Hunan Cancer Hospital from July 2016 to June 2018 were analyzed retrospectively. There were 130 females and 10 males, aging (35.4±9.8) years (range: 11 to 56 years). The operative time, intraoperative blood loss, postoperative hospital stay, postoperative suction drainage, postoperative pain score, postoperative cosmetic satisfaction and postoperative complications (recurrent laryngeal nerve palsy, hypoparathyroidism, infection, pneumoderm, seroma and mental nerve injury) were summarized. Results: Of the 140 patients, 1 patient was transferred to open surgery. Fifty-nine patients underwent thyroidectomy with an operation time of (100.8±18.9) minutes. Sixty-three patients underwent thyroidectomy and central lymphadenectomy with an operation time of (112.1±16.6) minutes. Eighteen cases underwent total thyroidectomy and central lymphadenectomy with an operation time of (185.3±25.9) minutes. The postoperative hospital stay was (3.76±0.98) days. The postoperative drainage was (96.8±36.2) ml. The 24-hour postoperative pain score was 2.66±1.23, the postoperative cosmetic satisfaction was 9.65±0.24. Among the postoperative complications, there were 3 cases of temporary recurrent laryngeal nerve palsy, 2 cases of permanent recurrent laryngeal nerve palsy, 4 cases of temporary hypoparathyroidism but no permanent hypoparathyroidism, 2 cases of infection, 1 case of seroma, 3 cases of pneumoderm, and no cases of mental nerve injury. Conclusion: The modified TOETVA by dissection of mental nerve is safe and feasible.

Beam Energy and Centrality Dependence of Direct-Photon Emission from Ultrarelativistic Heavy-Ion Collisions

The PHENIX collaboration presents first measurements of low-momentum (0.4<p_{T}<3  GeV/c) direct-photon yields from Au+Au collisions at sqrt[s_{NN}]=39 and 62.4 GeV. For both beam energies the direct-photon yields are substantially enhanced with respect to expectations from prompt processes, similar to the yields observed in Au+Au collisions at sqrt[s_{NN}]=200. Analyzing the photon yield as a function of the experimental observable dN_{ch}/dη reveals that the low-momentum (>1  GeV/c) direct-photon yield dN_{γ}^{dir}/dη is a smooth function of dN_{ch}/dη and can be well described as proportional to (dN_{ch}/dη)^{α} with α≈1.25. This scaling behavior holds for a wide range of beam energies at the Relativistic Heavy Ion Collider and the Large Hadron Collider, for centrality selected samples, as well as for different A+A collision systems. At a given beam energy, the scaling also holds for high p_{T} (>5  GeV/c), but when results from different collision energies are compared, an additional sqrt[s_{NN}]-dependent multiplicative factor is needed to describe the integrated-direct-photon yield.

Pathogenic germline mutation profile in Chinese lung cancers and related-driver mutation pattern

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Background: Many cancers could be driven by germline mutation exampled as BRCA1/2 in breast or ovarian cancer. However, the candidate predisposition variants for Chinese lung cancer are largely unknown. Methods: We reviewed 1797 Chinese lung cancer patients with paired tumor-normal samples sequenced by a 1021 gene panel. The annotation of germline variants within 95 selected susceptible genes was based on ACMG 2015 version guideline. Results: The frequency of patients identified with pathogenic or likely pathogenic (P/LP) germline variants were 5.95% (107 in 1797), which elevated to 10.1% (9 in 89) in patients younger than 40. Totally, 112 mutations from 35 genes were screened out. Recurrent pathogenic germline genes were BRCA2 (n = 14), FANCA (n = 9), RAD51D (n = 7), MUTYH (n = 7), ATM (n = 7) and TP53 (n = 5). The average age at diagnosis was numerically 2 years earlier in patients with P/LP (mean, 58.2 vs. 60.0, p = 0.22) than other patients without significance, but different genes contribute to discordant effects. Significantly early onset age was found in germline BRCA1/ 2 mutation (median, 52.5 versus 60.0 yrs in patients without P/LP, p = 0.0080) while later onset age was associated with germline PMS2 mutation (median, 74 versus 60.0 yrs, p = 0.0214 ). In terms of clinical actionable somatic mutation, the frequency of KRAS (15/89, 16.85% versus 121/1429, 8.47%, p = 0.012) and c-MET (6/89, 6.74% versus 31/1429, 2.17%, p = 0.018) in germline mutant patients were significantly higher, while TP53 (41/89, 46.07% versus 847/1429, 59.27%, p = 0.019) was apparently less mutated in P/LP lung cancer. As for frequency of EGFR, ALK, ROS-1, RET and BRAF, mutation frequency were not significantly different in lung cancer with germline mutation. Conclusions: Our study delineated the pathogenic germline mutation landscape in Chinese lung cancers for the first time. Predisposition genes demonstrated clinical actionable roles in onset age and therapeutic interventions. Further follow up may clarify the contribution of germline mutation to somatic mutation driven targeted therapy response and prognosis.

Molecular characterization of NSCLC-like and SCLC-like subsets in Chinese pulmonary large cell neuroendocrine carcinoma (LCNEC)

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Background: LCNEC is an aggressive, biologically heterogenous carcinoma which can be molecularly characterized as SCLC-like and NSCLC-like. Accurate distinction of molecular subset is of major clinical relevance since it may guide treatment choices in LCNEC. Here we determined the genomic characteristics of the two LCNEC subsets in a Chinese cohort to clarify their correlations with traditional lung cancer histologies. Methods: FFPE samples from 31 LCNECs were sequenced using a 520-cancer-related gene panel, with an average sequencing depth of 1353X. Comparative mutational analysis was conducted between NSCLC-like LCNECs from our cohort and adenocarcinomas from TCGA dataset. Results: Despite similar clinical features in terms of stage and age at diagnosis, NSCLC-like (42%, 13/31) and SCLC-like (32%, 10/31) subsets from LCNEC displayed distinct molecular characteristics. NSCLC-like subset harbored significant higher mutation frequencies of STK11, KEAP1 and FAT3 (53.8%, 38.5% and 38.5%, p = .007, .046 and .046), while SCLC-like subset was characterized by highly mutated RB1 (100%, p < .001) and PTEN (50%, p = .007). Compared with TCGA adenocarcinomas, NSCLC-like LCNEC displayed more frequent mutations in TP53, STK11, APC, KMT2D and SMARCA4 (76.9%, 53.8%, 30.8%, 30.8% and 23.1%; p = .043, .004, .045, .005 and .049). In addition, potential targetable alterations were present in 46.2% (6/13) pts of NSCLC-like subset. For those advanced stage pts, 2/5 NSCLC-like and 5/5 SCLC-like pts received relevant chemotherapy according to their molecular characteristics. The clinical outcomes of these pts are still under follow-up. Conclusions: This study demonstrates the distinct molecular features between NSCLC-like and SCLC-like subsets, and highlights the predominant genomic similarity and separate entities between NSCLC-like LCNEC with adenocarcinoma. Given the evidence that genomic profiling may aid in informing treatment decisions for pts with LCNEC, our study indicates that, based on accurate molecular typing, 46.2% NSCLC-like pts may benefit from potential targeted therapy and the rest of them may be more suitable to receive NSCLC-chemotherapy.

Characterization of genomic alterations in Chinese LCNEC and SCLC via comprehensive genomic profiling

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Background: LCNEC and SCLC are aggressive neuroendocrine carcinomas with overlap in clinical, histopathologic, morphologic and genomic features. Differential molecular features between the two subtypes have not been well elucidated, contributing the uncertainty for optimal clinical strategy for each subtype. Here we interrogated the genomic characteristics in LCNEC as compared to SCLC along with their histologically related subtypes: carcinoids and atypical carcinoids via comprehensive genomic profiling. Methods: FFPE samples from 31 LCNECs, 35 SCLCs, 14 carcinoids and 22 atypical carcinoids were sequenced in a CLIA-certified sequencing laboratory using 520-cancer-related gene panel, with an average sequencing depth of 1385×. Results: Comparative mutational analysis revealed that both LCNEC and SCLC sub-cohorts displayed higher rate of TP53 alterations than that of carcinoid (p < 0.001, p < 0.001). SCLC patients harbored more RB1 and PIK3CA mutations than LCNECs (p < 0.001, p = 0.014) and carcinoids (p < 0.001, p = 0.018). In addition, mutation frequencies of LRP1B, FAT1, PRKDC, NOTCH1, SPTA1, EPHA3 and KEAP1 in SCLC were significantly higher than that in carcinoid. Mutations in TP53 and RB1 occurred concurrently in 83% (29/35) SCLC patients, whereas in only 32.3% (10/31) LCNECs. We further investigated the distribution of mutations across KEGG pathways and found that mutation frequencies in both HIF-1 and Notch signaling pathways were lower in LCNEC than SCLC (p = 0.032, p = 0.025). Copy number variation (CNV) analysis revealed that LCNEC and SCLC had comparable CNVs which were significantly higher than carcinoid (p < 0.001, p < 0.001) and atypical carcinoid (p = 0.010, p = 0.028). TMB analysis also revealed a comparable TMB status of LCNEC (12.7/Mb) and SCLC (11.9/Mb), and relatively lower TMB in both carcinoid (2.4/Mb, p < 0.001, p < 0.001) and atypical carcinoid (5.6/Mb, p = 0.003, p = 0.009) than LCNEC and SCLC. Conclusions: We demonstrated the differential genomic characteristics in the four subtypes of neuroendocrine carcinomas. Compared with SCLC, LCNEC has lower mutation frequencies in RB1, PIK3CA, as well as HIF-1 and Notch signaling pathways. In addition, LCNEC and SCLC had comparable CNV and TMB status, which significantly higher than that of carcinoids and atypical carcinoid.

Pseudorapidity Dependence of Particle Production and Elliptic Flow in Asymmetric Nuclear Collisions of p+Al, p+Au, d+Au, and ^{3}He+Au at sqrt[s_{NN}]=200 GeV

Asymmetric nuclear collisions of p+Al, p+Au, d+Au, and ^{3}He+Au at sqrt[s_{NN}]=200  GeV provide an excellent laboratory for understanding particle production, as well as exploring interactions among these particles after their initial creation in the collision. We present measurements of charged hadron production dN_{ch}/dη in all such collision systems over a broad pseudorapidity range and as a function of collision multiplicity. A simple wounded quark model is remarkably successful at describing the full data set. We also measure the elliptic flow v_{2} over a similarly broad pseudorapidity range. These measurements provide key constraints on models of particle emission and their translation into flow.