Incidence of and risk factors for non-hematologic toxicity with combined radiotherapy and CDK4/6 inhibitors in metastatic breast cancer using dose-volume parameters analysis: a multicenter cohort study.

BACKGROUND: There is a lack of data on combined radiotherapy (RT) and cyclin-dependent kinase 4 and 6 inhibitor (CDK4/6i) risk factors and toxicity. This study aimed to assess the incidence of and risk factors for non-hematologic toxicities in patients treated with combined RT and CDK4/6i using dose-volume parameter analysis. METHODS: We conducted a retrospective multicenter cohort study of patients with metastatic breast cancer receiving RT within 14 days of CDK4/6i use. The endpoint was non-hematologic toxicities. Patient characteristics and RT treatment planning data were compared between the moderate or higher toxicities (≥ grade 2) group and the non-moderate toxicities group. RESULTS: Sixty patients were included in the study. CDK4/6i was provided at a median daily dose of 125 mg and 200 mg for palbociclib and abemaciclib, respectively. In patients who received concurrent RT and CDK4/6i (N = 29), the median concurrent prescribed duration of CDK4/6i was 14 days. The median delivered RT dose was 30 Gy and 10 fractions. The rate of grade 2 and 3 non-hematologic toxicities was 30% and 2%, respectively. There was no difference in toxicity between concurrent and sequential use of CDK4/6i. The moderate pneumonitis group had a larger lung V20 equivalent dose of 2 Gy per fraction and planning target volume than the non-moderate pneumonitis group. CONCLUSIONS: Moderate toxicities are frequent with combined RT and CDK4/6i. Caution is necessary concerning the combined RT and CDK4/6i. Particularly, reducing the dose to normal organs is necessary for combined RT and CDK4/6i.

Historical Review of Stereotactic Radiosurgery in Juntendo University.

Juntendo University Hospital is the second hospital in Japan to start stereotactic brain irradiation using linear accelerator (LINAC) system. This report details the historical transition of stereotactic irradiation, progress of treatment technology, and change of treatment method from the beginning to the Juntendo University Hospital and Juntendo Nerima Hospital. The hospital changed the use of cobalt to the LINAC system when it was rebuilt in 1993. Total body irradiation treatment for leukemia had started around the same time. A year later, in 1994, the hospital used their LINAC systems to perform stereotactic head irradiation, otherwise known as pinpoint irradiation. In 2005, Juntendo University Nerima Hospital was opened and in September of the same year, radiation therapy using the latest model of LINAC system at that time was initiated. This was the first among all Juntendo hospitals to start intensity-modulated radiation therapy (IMRT) and image-guided radiotherapy (IGRT). In 2014, a second LINAC system for IMRT and IGRT was equipped at the Juntendo Hongo Hospital. In 2021, the LINAC systems of the Juntendo University Nerima Hospital were replaced after 15 years of usage. The new method of SRS was started using a latest LINAC systems. In this paper, I introduce the technique and progress of SRS that I have experienced mainly in Juntendo University.

Late recurrence of a papillary thyroid carcinoma 37 years after hemithyroidectomy: Solitary, left cervical lymph node metastasis evident on fluorodeoxyglucose positron-emission tomography/computed tomography images revealing nodular uptake.

In patients with well-differentiated papillary thyroid carcinoma (PTC), late recurrence is very rare. It is unusual that 18F-fluorodeoxyglucose positron-emission tomography/computed tomography (PET/CT) shows hypermetabolic lesions in patients with well-differentiated PTC metastases. We demonstrate an exceptional case exhibiting a first relapse 37 years after hemithyroidectomy to treat PTC. Recurrent metastasis of a PTC should be considered as a differential diagnosis even if the elapsed time from the initial treatment is great. A left cervical lymphadenopathy, which exceptionally exhibited a hypermetabolic lesion on PET/CT, should be considered a metastatically well-differentiated PTC.

Achilles tendon after percutaneous surgical repair: serial MRI observation of uncomplicated healing.

OBJECTIVE: The purpose of this study was to prospectively explore the MRI features of normal healing of the expected residual tendon gap in the Achilles tendon after percutaneous surgical repair. SUBJECTS AND METHODS: MR images of the Achilles tendon were obtained approximately 4, 8, and 12 weeks after surgery. Assessment of MR images was focused on the presence of residual tendon gap and gap length, Achilles tendon contour, and contrast enhancement in the ruptured area. Cases of open surgical repair were used for comparison. We attempted to statistically compare the timing of tendon gap disappearance within the percutaneous surgical repair group and between the percutaneous and open surgical repair groups. RESULTS: A total of 30 tendons repaired with percutaneous surgical technique and 10 repaired with open surgical technique were evaluated. At the first, second, and third MRI sessions of the percutaneous surgical repair group, a residual gap was found in 100%, 80%, and none of the tendons on T1-weighted images and in 87%, 63%, and none of the tendons on T2-weighted images. Achilles tendon contour was visualized in 30%, 90%, and 100% of the tendons on T1-weighted images and 90%, 100%, and 100% of the tendons on T2-weighted images. Intratendinous enhancement was present in 100%, 73%, and 7% of the tendons in the percutaneous surgical repair group. Ring-shaped peritendinous enhancement was recognized at the third session in all subjects. A significantly longer time was required for tendon gap disappearance after percutaneous than after open surgical repair. CONCLUSION: The time course of the MR findings in the ruptured Achilles tendon after percutaneous surgical repair appears to reflect regular healing.

Comparing size evaluation methods for acoustic neuroma after stereotactic radiosurgery.

PURPOSE: Acoustic neuroma tumor size may be evaluated using several methods. Here we investigate the variations among measuring techniques. MATERIALS AND METHODS: A retrospective analysis of pre- and posttreatment magnetic resonance (MR) scans was performed on 15 acoustic neuroma patients with a history of stereotactic radiosurgery who had been followed for more than 2 years. Tumor size was measured on each MR scan using three methods, where the extracanalicular (EX) and intracanalicular (IN) portions were measured separately. We collected data on the largest diameter (M1), the square root of the product of the maximum anteroposterior and mediolateral diameter (M2), and the average for the maximum anteroposterior, mediolateral, and superoinferior diameters (M3). Size differences between follow-up MR scans separated by more than 2 years were calculated for each method, and we evaluated whether the tumors progressed, remained stable, or regressed. RESULTS: A total of 154 follow-up pairs of EX and 115 follow-up pairs of IN showed a statistically significant difference for the number of each category among the three methods (P = 0.03, P < 0.01, respectively). The greatest category agreement was observed between the M2 and M3 methods. CONCLUSION: A significant difference between the tumor size measuring methods was observed. To strengthen specificity when evaluating tumor size difference, a measuring method using two or more parameters is recommended.

Early Intake of Radiocesium by Residents Living Near the Tepco Fukushima Dai-ichi Nuclear Power Plant After the Accident. Part 2: Relationship Between Internal Dose and Evacuation Behavior in Individuals.

The Tokyo Electric Power Company's Fukushima Dai-ichi Nuclear Power Plant (FDNPP) accident exposed members of the public to radiation. This study analyses the relation between personal behavior data obtained from 112 out of 174 subjects who underwent whole-body measurements by the National Institute of Radiological Sciences (NIRS) during the period from 27 June to 28 July 2011 and their committed effective doses (CEDs) from Cs and Cs. The whereabouts of the 112 persons living in municipalities near the FDNPP (mainly, Namie town) on several days in March 2011 are graphed on maps. It was confirmed that most subjects started evacuation promptly and had left the 20-km-radius of the FDNPP by the end of 12 March. The individual CEDs were poorly correlated with the person's distances from the FDNPP at any day in March. Meanwhile, the percentage of persons remaining within the 20-km radius of the FDNPP was 100% at 16:00 on 12 March and 42.9% at 0:00 on 15 March for those with CEDs > 0.1 mSv, whereas the corresponding values were much lower for those with CEDs ≤ 0.1 mSv. This suggests that the time of evacuation would be one of the crucial factors for the early intake; however, more personal behavior data are needed to be analyzed to clarify the relevance to the individual internal dose.

Retained surgical sponge in the thigh: report of the third known case in the limb.

We report a retained surgical sponge (gossypiboma) in the thigh, which mimicked a neoplasm. A 25-year-old man, who had a past history of external fixation for femoral shaft fracture, complained of swelling in the left thigh with pain. A radiograph of the thigh showed periosteal reaction. T1-weighted magnetic resonance (MR) images showed a well-defined mass with heterogenous signal intensity, and T2-weighted images showed tortuous lines of low signal intensity within the mass. Surgical excision revealed a retained gauze sponge within the mass. Histopathological examination revealed foreign body reaction related to the retained gauze sponge. Our case, the third to our knowledge of gossypiboma in a limb, demonstrated characteristic MR imaging findings.

Internal radiation exposure of Ground Self-Defense Force members involved in the management of the Fukushima Nuclear Power Plant disaster.

When the Great East Japan Earthquake occurred on March 11, 2011, the Ground Self-Defense Force (GSDF) was dispatched nationally to Northeast area in Japan. The highly trained GSDF members were simultaneously assigned to various missions for the Fukushima Nuclear Power Plants disaster. The missions of GSDF terminated on August 31, 2011. Special medical examinations were conducted for the members as they returned to each military unit. GSDF members who were assigned to the nuclear power plant were at risk of radiation exposure; therefore, pocket dosimeters were used to assess external radiation exposure. A few months after the mission was terminated, measurements of internal radiation exposure were performed. This is the first report of the internal exposure of GSDF members who worked in the restricted radiation contamination area. Here, we report the amounts of internal and external exposure of and the equipment used by the GSDF members.

Pseudomesotheliomatous lung cancer mimicking mesothelioma on ¹8F-FDG PET/CT images: report of 2 cases.

The authors report two cases of pseudomesotheliomatous lung cancer (PLC) detected by (18)F-FDG PET/CT scan. (18)F-FDG PET/CT clearly revealed the extent of the disease in both cases, a case of adenocarcinoma of the lung and a case of squamous cell carcinoma of the lung. Intense (18)F-FDG uptake by the diffusely thickened pleurae and primary lesion was observed in both cases, and increased (18)F-FDG uptake by a pelvic bone metastasis was observed in the case of squamous cell carcinoma. Although PLC is indistinguishable from malignant pleural mesothelioma on (18)F-FDG PET/CT scans, (18)F-FDG PET/CT was helpful in identifying the primary focus of the PLCs and in staging the disease. Diagnostic image interpreters should be familiar with the (18)F-FDG PET/CT findings in PLC.

MR imaging of meniscal malformations of the knee mimicking displaced bucket-handle tear.

We report two cases of patients with lateral meniscal malformations of the knee that were found incidentally. Magnetic resonance imaging (MRI) of both cases showed a fragment-like meniscus structure located in the intercondylar notch, very similar to the "fragment in the intercondylar notch sign" observed in displaced bucket-handle tear. Arthroscopic examinations revealed a ring-shaped lateral meniscus in one case, and "flipped-over" lateral meniscus in the other. In the latter, a similar lateral meniscal malformation was observed contralaterally at MR arthrography.