論文

Variations in dose prescription methods in stereotactic body radiotherapy (SBRT) for early stage non-small-cell lung cancer (ES-NSCLC) make it difficult to properly compare the outcomes of published studies. We conducted a comprehensive search of the published literature to summarize the outcomes by discerning the relationship between local control (LC) and dose prescription sites. We systematically searched PubMed to identify observational studies reporting LC after SBRT for peripheral ES-NSCLC. The correlations between LC and four types of biologically effective doses (BED) were evaluated, which were calculated from nominal, central, and peripheral prescription points and, from those, the average BED. To evaluate information on SBRT for peripheral ES-NSCLC, 188 studies were analyzed. The number of relevant articles increased over time. The use of an inhomogeneity correction was mentioned in less than half of the articles, even among the most recent. To evaluate the relationship between the four BEDs and LC, 33 studies were analyzed. Univariate meta-regression revealed that only the central BED significantly correlated with the 3-year LC of SBRT for ES-NSCLC (p = 0.03). As a limitation, tumor volume, which might affect the results of this study, could not be considered due to a lack of data. In conclusion, the central dose prescription is appropriate for evaluating the correlation between the dose and LC of SBRT for ES-NSCLC. The standardization of SBRT dose prescriptions is desirable.

In the treatment of colorectal cancer patients with distant metastases, the development of new anticancer agents has considerably prolonged progression-free survival. Such survival benefits attributed to chemotherapy have increased the relative significance of local therapy in patients with limited metastases. The liver is recognized as the most common site of metastasis of colorectal cancer because of the intestinal mesenteric drainage to the portal veins. Hepatic resection of isolated liver metastases of colorectal cancer is the only option for a potential cure. However, hepatic metastases are resectable in only approximately 20% of the patients. For remaining patients with high-risk resectable liver metastases or those who are unfit for surgery, less invasive, local therapies including radiation therapy (stereotactic body radiation therapy, SBRT) may have a potential role in treatment. Although the local control rate of SBRT for colorectal liver metastases has room for improvement, its less-invasive nature and broad indications deserve consideration. Future research should include SBRT dose escalation or the selection of patients who benefit from local ablative therapies. SBRT may offer an alternative, non-invasive approach for the treatment of colorectal liver metastases in a multidisciplinary treatment strategy.

Purpose: We investigated whether delivery of a high biologically effective dose (BED) to primary tumors affects systemic outcomes of cancer-specific death (CSD) and overall survival (OS) rates after stereotactic body radiation therapy (SBRT) in patients with early-stage non-small cell lung cancer (ES-NSCLC). Methods and Materials: Among consecutive ES-NSCLC patients treated with SBRT between 2005 and 2019, we retrospectively identified patients who received a prescription of 50 to 60 Gy in 5 fractions with maximum doses of 62.5 to 100 Gy. Patients were categorized by maximum BED within the planning target volume with a threshold dose of 200 Gy. Outcomes were analyzed in all and matched patients. Results: Overall, 433 patients were eligible, and 262 and 171 patients were categorized into HighBED and LowBED groups, respectively. After propensity score matching, pairs of 154 patients were selected. Median follow-up times for the HighBED and LowBED groups were 52.3 months (range, 0.8-107.2 months) and 121.6 months (range, 3.0-162.8 months), respectively. The local recurrence rate in the HighBED group was significantly lower than that in the LowBED group (5-year rate, 1.3% and 7.2%; hazard ratio [HR], 0.15; 95% confidence interval [CI], 0.03-0.65; P = .011). Rates of any recurrence and CSD in the HighBED group were significantly lower (5-year any recurrence: 18.1% and 32.1%; HR, 0.52; 95% CI, 0.33-0.83; P = .0058; 5-year CSD: 9.5% and 21.8%; HR, 0.38; 95% CI, 0.20-0.70; P = .002), and OS in the HighBED group was significantly better compared with the LowBED group (5-year rate: 61.7% and 51.8%; HR, 0.71; 95% CI, 0.50-1.00; P = .047). Conclusion: In patients with peripheral ES-NSCLC, SBRT with a high maximum dose may improve not only local control, but also any recurrence, CSD, and OS rates without increased toxicity. Further trials designed to evaluate whether higher intensity SBRT increases local control rates and contributes to improved CSD and OS outcomes are anticipated.

AbstractBACKGROUND.Breast cancer is likely to have systemic involvement. However, to the authors' knowledge there are few reports to date regarding clinically detected patterns of metastasis, meticulously studied in regard to the natural history of breast cancer, including unusual sites of metastasis.METHODS.Patients treated for invasive breast cancer from April 1983 to May 2007 were retrospectively analyzed. Patterns of clinically apparent tumor recurrence, focusing especially on unusual metastases, were studied as well as possible risk factors for unusual metastases and their influence on survival.RESULTS.Overall, 3783 patients were eligible for the current analysis. The median duration of follow‐up was 5.0 years (range, 0.6 years–20.4 years). Cumulative 5‐year and 10‐year survival rates were 89.7% and 81.5%, respectively. “Unusual metastasis” was defined as systemic failure with a frequency of ≤1%; in the current series; it was observed in 85 (2.2%) patients %. Of those, 70 (82%) had preceding metastasis in the usual sites. The median duration until the development of usual and unusual metastasis was 2.3 years and 3.6 years, respectively (P < .0001). Among764 patients with distant metastasis, the 5‐year cumulative overall survival rate in those with or without unusual metastasis was 53.5% and 53.4 years, respectively (P = .33). No risk factors for unusual metastasis were identified.CONCLUSIONS.This retrospective study examined the frequency of unusual metastases in a large number of Japanese patients with initially nonmetastatic breast cancer. The prognosis of patients with unusual metastases was found to be similar to that of patients with metastasis only at more usual sites. Cancer 2008. © 2008 American Cancer Society.

BACKGROUNDCurative treatment options for patients with early stage hepatocellular carcinoma (HCC) include resection, liver transplantation, and percutaneous ablation therapy. However, even patients with solitary HCC are not always amenable to these treatments. The authors prospectively investigated the clinical outcomes of patients who received stereotactic body radiotherapy (SBRT) for solitary HCC.METHODSA phase 2 study involving SBRT and optional transarterial chemoembolization (TACE) was conducted in patients with Child‐Pugh grade A or B and underlying, solitary HCC (greatest tumor dimension, ≤4 cm) who were unsuitable candidates for resection and radiofrequency ablation. The prescription dose was 35 to 40 grays in 5 fractions. The primary endpoint was 3‐year local tumor control.RESULTSFrom 2007 to 2012, 101 patients were enrolled, and 90 were evaluable with a median follow‐up of 41.7 months (range, 6.8‐96.2 months). Thirty‐two patients were treatment‐naïve, 20 were treated for newly diagnosed intrahepatic failure, and 38 were treated for residual or recurrent HCC as salvage therapy. Thirty‐two patients did not receive TACE, 48 received insufficient TACE, and 10 attained full lipiodol accumulation. The 3‐year local control rate was 96.3%, the 3‐year liver‐related cause‐specific survival rate was 72.5%, and the overall survival rate was 66.7%. Grade 3 laboratory abnormalities were observed in 6 patients, and 8 patients had Child‐Pugh scores that worsened by 2 points.CONCLUSIONSSBRT achieved high local control and overall survival with feasible toxicities for patients with solitary HCC, despite rather stringent conditions. SBRT can be effective against solitary HCC in treatment‐naive, intrahepatic failure, residual disease, and recurrent settings, taking advantage of its distinctive characteristics. Cancer 2016;122:2041–9. © 2016 American Cancer Society.

AbstractBACKGROUNDProphylactic cranial irradiation (PCI) reduces the incidence of brain metastasis with an effect on overall survival in patients with small cell lung carcinoma (SCLC). In spite of multidisciplinary intensive treatment approaches, many patients still experience brain metastasis. The authors retrospectively analyzed the characteristics of the first failure event due to brain metastasis (FBM) in patients treated with PCI.METHODSBetween January 1990 and April 2004, 71 patients with limited disease SCLC were treated with PCI after completing systemic treatment at the National Cancer Center Hospital (Tokyo, Japan). Univariate and multivariate analyses were used to identify factors related to FBM and survival.RESULTSThe FBM and overall incidence of brain metastasis (OBM) were 16.9 % (12 of 71) and 26.8% (19 of 71), respectively. Median time to progressive disease and median survival were 8.4 months and 21.6 months, respectively. Elevation of pro‐gastrin–releasing peptide (Pro GRP) level before PCI was found to be a significant predictive and prognostic factor for FBM, OBM, and survival on multivariate analysis (P = 0.007, P = 0.025, and P = 0.009, respectively).CONCLUSIONSAn elevated Pro GRP level before PCI was found to be significantly related to FBM and survival, and should be considered before PCI is performed. Cancer 2005. © 2005 American Cancer Society.