Production of Sustainable Aviation Fuel by Hydrocracking of n-Heptadecane Using Pt-Supported Y-Zeolite-Al2O3 Composite Catalysts.

Hydrocracking of fat or Fischer-Tropsch (FT) wax from biomass to produce the jet fuel of sustainable aviation fuel has been one of the key reactions. n-Heptadecane, which is one of the model diesel fractions produced from fat or FT wax, has hardly been used for hydrocracking of hydrocarbon for jet fuel production, while n-hexadecane has often been used as one of the model compounds for this reaction. In the present study, a HY-zeolite (50 wt %, SiO2/Al2O3 = 100)-Al2O3 (50 wt %) composite-supported Pt (0.5 wt %) catalyst [0.5Pt/Y(100)35A] was tested for hydrocracking of n-heptadecane using a fixed-bed flow reactor at a H2 pressure of 0.5 MPa, H2 flow rate of 300 mL/min, WHSV of 2.3 h-1, and a catalyst weight of 2 g. Fine-tuning of the temperature to 295 °C achieved the highest selectivity of 74% for the jet fuel fraction C8-C15 with the high conversion of 99%. The jet fuel yield reached 73%, which was almost an ideal maximum yield of 75%. Similar hydrocracking of n-hexadecane has just reported the maximum yield of 51% for jet fuel fraction. Further, 0.5Pt/Z(110)35A, which has a composition similar to that of 0.5Pt/Y(100)35A except for the type of zeolite, could not give as high yield of jet fuel as 0.5Pt/Y(100)35A because the rapid conversion to lighter fractions than the jet fuel occurred by the slight increase in the reaction temperature even at a lower temperature range.

Number of dye marks required in virtual-assisted lung mapping.

OBJECTIVES: Virtual-assisted lung mapping is a preoperative bronchoscopic multi-spot dye-marking technique used in sublobar lung resection for hardly palpable lung nodules. However, the number of marks required per nodule remains unknown. Therefore, we examined the correlation between the number of intraoperative visible marks and the successful resection rate. METHODS: We retrospectively examined 210 consecutive patients with 256 lesions who underwent virtual-assisted lung mapping during January 2014-December 2020 at our hospital. When a nodule was not resected at the initial attempt, or when a nodule was very close to the cut margin in the resected specimen and required additional resection, we categorized it as unsuccessful resection. We divided 256 lesions into successful and unsuccessful groups and compared the numbers of intraoperative visible marks between the two groups. RESULTS: Of 797 attempted marks, 738 (92.4%) were visible during the surgery. Fourteen (5.4%) of 256 lesions were determined to be unsuccessful according to the study criteria. There was a remarkable difference in the average numbers of intraoperative visible marks between both groups (3 [interquartile range: 2-4] vs. 2 [interquartile range: 1-2.8]; p < 0.01). Multivariable logistic analysis revealed a significant difference in the number of intraoperative visible marks (odds ratio: 0.28, 95% confidence interval: 0.14-0.57; p < 0.001) between both groups. CONCLUSIONS: Successful sublobar lung resection requires three or more intraoperative visible marks established using virtual-assisted lung mapping per lung nodule.

A case of pulmonary sclerosing pneumocytoma diagnosed preoperatively using transbronchial cryobiopsy.

BACKGROUND: The preoperative diagnosis of pulmonary sclerosing pneumocytoma (PSP) is complicated since PSP has several histological structural patterns in the same neoplasm; hence, it is sometimes pathologically misdiagnosed as adenocarcinoma or carcinoid. In recent years, with the prevalence of transbronchial cryobiopsy (TBLC), we are able to obtain larger specimens than previously. However, to date, there have been no reports describing PSP diagnosed using TBLC. CASE REPORTS: A 43-year-old man was referred to our hospital for an abnormal lesion in the left lung discovered on routine health examination. A computed tomography scan of the chest revealed a 14-mm heterogeneous round nodule with surrounding ground-glass opacity in the left lower lobe. The tumor size increased to 18 mm in three weeks, and he developed bloody sputum. TBLC was performed using radial endobronchial ultrasonography and fluoroscopy. An occlusion balloon and prophylactic epinephrine were used to prevent severe bleeding. Histologically, epithelioid cells with solid proliferation, various papillary lesions, and hemosiderin-laden histiocytes were observed. Immunohistochemical staining revealed the histiocytes positive for thyroid transcription factor-1 and vimentin, and the type II pneumocyte-like-cells positive for cytokeratin 7. The tumor was preoperatively diagnosed as a PSP; the patient underwent left basal segmentectomy and consequently, a final diagnosed of PSP was formulated. CONCLUSION: We report the first case of PSP preoperatively diagnosed using TBLC. Therefore, cryobiopsy could be beneficial in the preoperative diagnosis of PSP.

Impact of Previous Malignancy on Outcome in Surgically Resected Non-Small Cell Lung Cancer.

BACKGROUND: Patients with lung cancer with a history of treatment often undergo curative surgical resection. However, the impact of previous cancer treatment on the outcome of lung cancer remains unclear. METHODS: We conducted a retrospective study of patients who underwent curative resection for non-small cell lung cancer between 1998 and 2011. We collected clinicopathologic data and patients were divided into groups by previous history of cancer treatment. Comparisons between groups, estimation of survival rates, and multivariate analyses were performed. Propensity score matching was used to create cohorts with reduced bias. RESULTS: Of 878 patients, 196 (22.3%) had previous extrathoracic malignancies, and stage I lung cancer was more frequent in this group (P < .001). In multivariate analysis of the whole cohort, older patients, men, non-adenocarcinoma histologic type, more advanced pathologic stage of lung cancer, interstitial pneumonia, and previous extrathoracic malignancies were associated with appreciably worse prognosis. When propensity score matched cohorts were compared, prognosis was significantly worse in patients with previous extrathoracic malignancies than patients without (5-year survival rates, 75.3% vs 82.7%; P = .009), although recurrence was not frequently seen (5-year recurrence-free rates, 78.7% vs 83.0%; P = .491). CONCLUSIONS: Because treatment history of extrathoracic malignancy was not associated with postsurgical lung cancer recurrence, proposing curative resection could be justifiable if the previous cancer is deemed cured or controlled. However, the results showing that patients with previous cancer history have a worse survival rate than patients without should be taken into account when curative surgery is considered.

Bilateral segmentectomies using virtual-assisted lung mapping (VAL-MAP) for metastatic lung tumors.

BACKGROUND: Virtual-assisted lung mapping (VAL-MAP) has been used not only in wedge resection but also in segmentectomy for hardly palpable lung nodules. We herein report a case of bilateral segmentectomy using VAL-MAP with chronological change of pulmonary function test results. CASE PRESENTATION: A 50-year-old female was found to have a colorectal cancer with pulmonary nodules in both sides of the lungs considered as synchronous lung metastases. After sigmoidectomy for primary cancer and chemotherapy, treatments for small nodules in both sides of the lungs were planned. Most nodules were small and supposed to be impalpable. We performed thoracoscopic segmentectomy of right S8 with the aid of VAL-MAP and, after 2 months, combined subsegmentectomy of left S8a and 9a and wide wedge resection of left S8b with the aid of VAL-MAP. All nodules suspected of lung metastases were successfully resected with adequate margins, and the decrease in pulmonary function was minimal compared with predicted postoperative forced vital capacity (FVC) and forced expiratory volume (FEV) 1.0 calculated by the numbers of subsegments. CONCLUSIONS: Bilateral segmentectomies of small impalpable metastatic tumors were performed successfully with the aid of VAL-MAP.

Impact of portal vein invasion and resection length in pancreatoduodenectomy on the survival rate of pancreatic head cancer.

BACKGROUND/AIMS: A positive surgical margin is a poor prognosis factor. Resection of the invaded portal vein (PV) may be necessary to achieve a negative surgical margin during pancreaticoduodenectomy (PD). This study clarifies the intraoperative and long-term survival of patients who received PD with PV resection compared to without. METHODOLOGY: Between July 1992 and March 2012, a retrospective analysis of 119 patients undergoing PD with or without PV resection for pancreatic head cancer was performed. Main outcome measures were perioperative mortality and survival rate of PD with and without PV resection. RESULTS: Perioperative mortality was not different between PD (1 of 51 cases: 2.0%) and PD with PV resection (3 of 68 cases: 4.4%) (p = 0.462). Patients without resection had a significantly better prognosis than patients with PV resection (p = 0.0052). Patients on whom >2.1 cm of the PV was resected (n = 34) had a worse cumulative survival rates than patients with a resection of <2.1 cm (n = 19) (p = 0.0380). Patients with no invasion of PV wall (n = 18) had a significantly higher survival rate than positive PV wall invasion (n = 49) (p =0.039). CONCLUSIONS: Patients with PV resection had a significantly worse prognosis than patients without PV resection. Some patients survived more than 5 years post-operation after PD with PV resection. PV resection contributes to attaining complete tumor resection.