Published papers

AbstractBackground and AimsStereotactic ablative body radiotherapy (SABR) is a relatively new treatment for hepatocellular carcinoma (HCC). The outcomes of SABR for previously untreated solitary HCC unfit for ablation and surgical resection were evaluated.MethodsUntreated solitary HCC patients treated with SABR were retrospectively studied. Between 2005 and 2012, 221 HCC patients underwent SABR. Among them, patients with untreated solitary HCC, treated with only SABR or SABR preceded by transarterial chemoembolization, were eligible. Based on baseline liver function and liver volume receiving ≥ 20 Gy, 35–40 Gy in five fractions was prescribed to the planning target volume surface.ResultsSixty‐three patients were eligible, with a median follow‐up duration of 31.1 (range 12.0–88.1) months. No patients were lost to follow‐up. Twenty patients were treated with only SABR. In 43 patients treated with SABR preceded by transarterial chemoembolization, accumulation of lipiodol in the tumor remained complete in five, a partial defect in 38 on pre‐SABR computed tomography. The 1‐, 2‐, and 3‐year local control rates were 100%, 95%, and 92%, respectively; the intrahepatic recurrence‐free rates were 76%, 55%, and 36%, respectively; and the overall survival rates were 100%, 87%, and 73%, respectively. Grade 3 laboratory toxicities in the acute, subacute, and chronic phases were observed in 10, 9, and 13 patients, respectively, and ascites occurred in one patient.ConclusionsLocal control and overall survival after SABR for untreated solitary HCC were excellent despite the candidates being unfit for resection and ablation. SABR is safe and might be an alternative to resection and ablation.

Background. Liver metastases are common in patients with small-cell lung cancer (SCLC) and are associated with a poor prognosis. Recent reports, mainly from abroad, have demonstrated the efficacy of palliative radiotherapy for liver metastases, but this therapy has not been widely used or reported in Japan. Case. Since late June, 20XX−1, a 76-year-old man had been treated with carboplatin, etoposide, and durvalumab for extensive-disease SCLC. After completing six treatment cycles, the patient was undergoing maintenance therapy with durvalumab. Owing to worsening of the primary lesion, liver metastases, and para-aortic lymph node metastases, the patient was admitted to our hospital on late February, 20XX, for treatment modification. Since more than 90 days had passed since the last dose of etoposide, a sensitive relapse was considered, and carboplatin plus etoposide therapy was initiated. However, back pain and jaundice appeared and became severe, requiring the initiation of regular opioid therapy. The symptoms were suggestive of capsular extension due to the rapid growth of multiple liver metastases, prompting whole liver radiotherapy (21 Gy/7 fr) to alleviate pain. There was a temporary increase in pain due to a flare reaction, requiring a temporary increase in opioid and steroid doses, but the symptoms rapidly resolved, and the patient was discharged with independent gait. The patient was subsequently readmitted and switched to amrubicin therapy. Approximately one month after whole liver radiotherapy, all symptoms and multiple liver metastases were under control. Conclusion. SCLC is radiosensitive and responds well to low-dose radiotherapy. Radiation-induced liver disease is unlikely to occur at low doses, and whole liver radiotherapy is considered effective even in patients with treatment-resistant SCLC.

The Japanese Breast Cancer Society initiated the breast cancer registry in 1975 and migrated the registry to the National Clinical Database-Breast Cancer Registry (NCD-BCR) in 2012. This annual report presents 2021 data on the NCD-BCR. We analyzed data from 98,540 breast cancer (BC) cases registered in 2021. In 2021, 99.4% of BC cases were females with a median age of 61. Most (57.5%) were diagnosed at early stages (Stage 0 or I). Breast-conserving surgery was performed in 42.8% of cases. Sentinel lymph node biopsy was performed in 67.8%, followed by radiotherapy in 71.0% of those post-conserving surgery. Regarding postoperative systemic therapy, 63.1% received endocrine therapy, 28.2% received chemotherapy, and 14.9% received molecular-targeted therapy. ER positivity was observed in 75.2%, HER2 in 13.6%, and Ki67 ≥30% in 29.1% of cases. The median age of premenopausal cases was 46 (interquartile range, 42–49) years and the median BMI was 21.5 (19.7–24.2) kg/m2 whereas the median age of postmenopausal cases was 69 (61–76) years and the median BMI was 23.0 (20.6–25.9) kg/m2. In premenopausal cases, cases with normal BMI were more likely to be found at checkups without subjective symptoms and in the early stage than those with high BMI. The tendency of ER, PgR, HER2, and Ki67 status on BMI differed by menopause status; premenopausal cases with a lower BMI showed higher proportions of ER- and PgR-positive cancer and lower proportions of cancer with high Ki67. These nationwide descriptive statistics would help clinical explanation and further research on breast cancer.

This is an annual report by the Japanese Breast Cancer Society regarding the clinical data on breast cancer extracted from the National Clinical Database-Breast Cancer Registry (NCD-BCR) of Japan. Here, we present an updated summary of 98,300 breast cancer cases registered in 2019. The median age at cancer diagnosis was 61 years (interquartile range 49–72 years), and 30.6% of the breast cancer patients were premenopausal. Of the 93,840 patients without distant metastases, 14,118 (15.0%) and 42,047 (44.8%) were diagnosed with stage 0 and I disease, respectively. Breast-conserving surgery was performed in 42,080 (44.8%) patients. Regarding axillary procedures, 62,677 (66.8%) and 7371 (7.9%) patients underwent sentinel node biopsy and axillary node dissection after biopsy, respectively. Whole breast irradiation was administered to 29,795 (70.8%) of the 42,080 patients undergoing breast-conserving surgery. Chest wall irradiation was administered to 5524 (11.1%) of the 49,637 patients who underwent mastectomy. Of the 6912 clinically lymph node-negative patients who received preoperative therapy, 5250 (76.0%) and 427 (6.2%) underwent sentinel node biopsy and axillary node dissection after biopsy, respectively; however, 602 (8.7%) patients initially underwent axillary node dissection without biopsy.

This is an annual report by the Japanese Breast Cancer Society, which provides statistics on the clinical data on breast cancer in Japan, extracted from the National Clinical Database-Breast Cancer Registry (NCD-BCR). This report includes an update of 102,453 breast cancer cases at 1339 institutions registered in the NCD-BCR in 2022. Among the 101,793 female patients, the median age at cancer diagnosis was 62 years (interquartile range, 50–73 years), and 29.4% of the patients were premenopausal. Of these patients, 15,437 (15.2%) and 42,936 (42.2%) were diagnosed with stage 0 and I disease, respectively. Estrogen receptor, progesterone receptor, and human epidermal growth factor receptor 2 (HER2) were positive in 78.7%, 69.4%, and 12.8% of the patients, respectively. Of the 97,154 patients without distant metastasis, 40,521 (41.7%) underwent breast-conserving surgery, and 5780 (5.9%) patients underwent some form of breast reconstruction procedures at the time of mastectomy. A total of 66,894 (68.9%) patients were treated with sentinel lymph node biopsy and 7155 (7.4%) patients were treated with sentinel lymph node biopsy followed by axillary node dissection. In the group of patients treated with breast-conserving surgery (n = 40,521), 29,500 (72.8%) received whole-breast irradiation. In the group of patients who underwent mastectomy (n = 54,476), 6226 (11.4%) received radiation therapy to the chest wall. Of the 13,950 patients receiving preoperative chemotherapy with or without molecular targeted therapy, 4308 (30.9%) achieved a pathological complete response, with the highest rate of 60.5% in patients with the hormone receptor-negative/HER2-positive subtype.

Aim: Stereotactic body radiotherapy (SBRT) is an emerging treatment for hepatocellular carcinoma (HCC) and has shown excellent local control (LC), as has radiofrequency ablation (RFA). As no randomized controlled trial has compared SBRT and RFA for HCC, data from a propensity score matched study (PSMS) are valuable. However, the results varied greatly and depended on composing factors of Barcelona Clinic Liver Cancer staging (BCLC-factors) adjusted. Therefore, we undertook a systematic review and meta-analyses of the studies focusing on BCLC-factors matching. Methods: We systematically searched PubMed, the Cochrane database, EMBASE, and Web of Science to identify studies comparing RFA and SBRT using propensity scores. The hazard ratios (HRs) of overall survival (OS) and LC from BCLC-factor-matched and -unmatched PSMS were pooled. Heterogeneity between the data from these studies was assessed. Results: Three BCLC-factor-matched studies were identified. Stereotactic body radiotherapy led to comparable OS (HR, 0.89; 95% CI, 0.74–1.08; p = 0.24; I2 = 0%; p for heterogeneity, 0.56) and significantly better LC (HR, 0.39; 95% CI, 0.30–0.51; p < 0.001; I2 = 0%; p for heterogeneity, 0.67). We also identified three additional BCLC-factor-unmatched studies (HR of OS, 1.41; 95% CI, 1.21–1.65; p < 0.0001; I2 = 0%; p for heterogeneity, 0.63). However, considerable heterogeneity was observed for HR of OS between BCLC-factor-matched and -unmatched studies (I2 = 92.6%; p for heterogeneity, 0.0002). Conclusions: When BCLC-factors were properly adjusted, the results of the meta-analysis revealed equivalent OS and better LC for SBRT compared with RFA. Stereotactic body radiotherapy could be an alternative treatment option for HCC.

Background: This study investigated whether the dose distribution of lung cancer can be improved by dynamic arc conformal radiotherapy (dynamic CRT) compared with static multiple-beam radiotherapy (static CRT). Materials and methods: A dummy study of static CRT and dynamic CRT was performed, designed to meet the predetermined dose constraints. A dose of 60 Gy in 30 fractions was administered using two dose prescription methods: dose prescribed to the isocenter (IC prescription), and dose prescribed to > 50% of the planning target volume (D50 prescription). Dose–volume parameters were compared between the plans. Results: Among 20 patients with locally advanced lung cancer, dose conformity was significantly better with dynamic CRT than static CRT (median conformity index: 1.3 vs. 2.2; p < 0.01). As for the lung dose, compared with static CRT, dynamic CRT did not increase the percentage lung volume receiving ≥ 20 Gy (18.9% vs. 19.3%, p = 0.09). The maximum spinal cord dose was significantly reduced by dynamic CRT (static vs. dynamic CRT: 44.1 vs. 25.2 Gy, p < 0.001). With the change from IC to D50 prescription, the 95% isodose volume increased by 18.3 cc in static CRT and by 4.1 cc in dynamic CRT, while doses to the lung and spinal cord remained within the acceptable ranges. Conclusion: The dynamic CRT technique showed better target coverage and lower doses to the spinal cord in exchange for increased low-dose lung area, compared with static CRT. Dynamic CRT with D50 prescription instead of prescription to the isocenter has excellent dose distribution profiles without compromising doses to organs at risk for lung cancer at favorable locations.