Insufficiency fracture occurs when normal or physiological stress applied to weakened bone with demineralization and decreased elastic resistance. Recently, many studies reported the development of IF after radiation therapy (RT) in gynecological cancer, prostate cancer, anal cancer and rectal cancer. The RT-induced insufficiency fracture is a common complication during the follow-up using modern imaging studies. The clinical suspicion and knowledge the characteristic imaging patterns of insufficiency fracture is essential to differentiate it from metastatic bone lesions, because it sometimes cause severe pain, and it may be confused with bone metastasis.
Anus Neoplasms ; Follow-Up Studies ; Fractures, Stress* ; Neoplasm Metastasis ; Prostatic Neoplasms ; Rectal Neoplasms ; Stress, Physiological

PURPOSE: We designed this study to identify and suggest the reasonable timing of adjuvant radiotherapy in the treatment of uterine carcinosarcoma according to the surgical intent and patterns of progression. MATERIALS AND METHODS: We retrospectively analyzed a total of 50 carcinosarcoma patients diagnosed between 1995 and 2010. Among these 50 patients, 32 underwent curative surgery and 13 underwent maximal tumor debulking surgery. The remaining five patients underwent biopsy only. Twenty-six patients received chemotherapy, and 15 patients received adjuvant radiotherapy. RESULTS: The median follow-up period was 17.3 months. Curative resection (p < 0.001) and stage (p < 0.001) were statistically significant factors affecting survival. During follow-up, 30 patients showed progression. Among these, eight patients (16.0%) had loco-regional progression only. The patients who had received adjuvant radiotherapy did not show loco-regional progression, and radiotherapy was a significant negative risk factor for loco-regional progression (p = 0.01). The time to loco-regional progression was much earlier for non-curative than curative resection (range, 0.7 to 7.6 months vs. 7.5 to 39.0 months). CONCLUSION: Adjuvant radiotherapy in the treatment of carcinosarcoma might be related to a low loco-regional progression rate. Radiotherapy should be considered in non-curatively resected patients as soon as possible.
Biopsy ; Carcinosarcoma ; Follow-Up Studies ; Humans ; Radiotherapy, Adjuvant ; Retrospective Studies ; Risk Factors

Surgical resection is the mainstay of treatment for locally advanced esophageal cancer.Neoadjuvant therapy is recommended to improve survival, based on the results of severalrandomized trials and meta-analyses. However, controversy remains regarding howto combine surgery, radiotherapy, and chemotherapy. Moreover, in East Asia, the predominanthistological type is esophageal squamous cell carcinoma, which has a differentepidemiology and tumor biology from esophageal or gastroesophageal junctional adenocarcinoma.As such, the management of esophageal cancer in East Asia seems to bedifferent from that in Western countries. Thus, this article reviews the current evidence onneoadjuvant therapy and considers the optimal combinations and ongoing strategies ofmultimodal therapy for esophageal squamous cell carcinoma.

Intensity-modulated radiation therapy (IMRT) using X-rays is a standard technique implemented for treating head and neck cancer (HN C). Compared to 3D conformal RT, IMRT can significantly reduce the radiation dose to surrounding normal tissues by using a highly conformal dose to the tumor. Proton therapy is a type of RT that uses positively charged particles named protons. Proton therapy has a unique energy deposit (i.e., Bragg peak) and greater biological effectiveness than that of therapy using X-rays. These inherent properties of proton therapy make the technique advantageous for HNC treatment. Recently, advanced techniques such as intensity-modulated proton therapy have further decreased the dose to normal organs with a higher conformal dose to the tumor. The usage of proton therapy for HNC is becoming widespread as the number of operational proton therapy centers has increased worldwide. This paper aims to present the current clinical evidence of proton therapy utility to HNC clinicians through a literature review. It also discusses the challenges associated with proton therapy and prospective development of the technique.

Intensity-modulated radiation therapy (IMRT) using X-rays is a standard technique implemented for treating head and neck cancer (HN C). Compared to 3D conformal RT, IMRT can significantly reduce the radiation dose to surrounding normal tissues by using a highly conformal dose to the tumor. Proton therapy is a type of RT that uses positively charged particles named protons. Proton therapy has a unique energy deposit (i.e., Bragg peak) and greater biological effectiveness than that of therapy using X-rays. These inherent properties of proton therapy make the technique advantageous for HNC treatment. Recently, advanced techniques such as intensity-modulated proton therapy have further decreased the dose to normal organs with a higher conformal dose to the tumor. The usage of proton therapy for HNC is becoming widespread as the number of operational proton therapy centers has increased worldwide. This paper aims to present the current clinical evidence of proton therapy utility to HNC clinicians through a literature review. It also discusses the challenges associated with proton therapy and prospective development of the technique.

PURPOSE: To develop the dose volume histogram (DVH) management software which guides the evaluation of radiotherapy (RT) plan of a new case according to the biological consequences of the DVHs from the previously treated patients. MATERIALS AND METHODS: We determined the radiation pneumonitis (RP) as an biological response parameter in order to develop DVH management software. We retrospectively reviewed the medical records of lung cancer patients treated with curative 3-dimensional conformal radiation therapy (3D-CRT). The biological event was defined as RP of the Radiation Therapy Oncology Group (RTOG) grade III or more. RESULTS: The DVH management software consisted of three parts (pre-existing DVH database, graphical tool, and Pinnacle3 script). The pre-existing DVH data were retrieved from 128 patients. RP events were tagged to the specific DVH data through retrospective review of patients' medical records. The graphical tool was developed to present the complication histogram derived from the pre-existing database (DVH and RP) and was implemented into the radiation treatment planning (RTP) system, Pinnacle3 v8.0 (Phillips Healthcare). The software was designed for the pre-existing database to be updated easily by tagging the specific DVH data with the new incidence of RP events at the time of patients' follow-up. CONCLUSION: We developed the DVH management software as an effective tool to incorporate the phenomenological consequences derived from the pre-existing database in the evaluation of a new RT plan. It can be used not only for lung cancer patients but also for the other disease site with different toxicity parameters.
Humans ; Incidence ; Lung Neoplasms ; Medical Records ; Radiation Pneumonitis ; Retrospective Studies

The funding acknowledgment in this article was partially omitted as published.

Avascular necrosis (AVN) is a disease characterized by the temporary or permanent loss of the blood supply to the bones, resulting from many possible causes, including radiation therapy. The femoral head is known to be the most common site of AVN. The authors encountered two cases of AVN of the femoral head among 557 patients with cervical cancer treated with whole pelvic radiation therapy at the Samsung Medical Center. AVN of the femoral head was presented with a sclerotic density change in a plain roentgenography and a decreased signal intensity lesion on the T1 and T2 weighted phases of a magnetic resonance image (MRI). Although it is a very rare complication after whole pelvic radiation therapy, AVN of the femoral head should be considered when characteristic imaging findings appear on follow-up examinations.
Femur ; Femur Head ; Follow-Up Studies ; Head ; Humans ; Magnetic Resonance Spectroscopy ; Necrosis ; Uterine Cervical Neoplasms

PURPOSE: The purpose of this study is to evaluate the prognostic significance of the tumor volume reduction rate (TVRR) measured during adaptive definitive radiation therapy (RT) for nasopharyngeal cancer (NPC). MATERIALS AND METHODS: We reviewed the RT records of 159 NPC patients treated with definitive RT with or without concurrent chemotherapy between January 2006 and February 2013. Adaptive re-planning was performed in all patients at the third week of RT. The pre- and mid-RT gross tumor volumes (GTVs) of the primary tumor and the metastatic lymph nodes were measured and analyzed for prognostic implications. RESULTS: After a median follow-up period of 41.5 months (range, 11.2 to 91.8 months) for survivors, there were 43 treatment failures. The overall survival and progression-free survival (PFS) rates at 5 years were 89.6% and 69.7%, respectively. The mean pre-RT GTV, mid-RT GTV, and TVRR were 45.9 cm3 (range, 1.5 to 185.3 cm3), 26.7 cm3 (1.0 to 113.8 cm3), and -41.9% (range, -87% to 78%), respectively. Patients without recurrence had higher TVRR than those with recurrence (44.3% in the no recurrence group vs. 34.0% in the recurrence group, p=0.004), and those with TVRR > 35% achieved a significantly higher rate of PFS at 5 years (79.2% in TVRR > 35% vs. 53.2% in TVRR ≤ 35%; p < 0.001). In multivariate analysis, TVRR was a significant factor affecting PFS (hazard ratio, 2.877; 95% confidence interval, 1.555 to 5.326; p=0.001). CONCLUSION: TVRR proved to be a significant prognostic factor in NPC patients treated with definitive RT, and could be used as a potential indicator for early therapeutic modification during the RT course.
Disease-Free Survival ; Drug Therapy ; Follow-Up Studies ; Humans ; Lymph Nodes ; Multivariate Analysis ; Nasopharyngeal Neoplasms* ; Radiotherapy ; Recurrence ; Survivors ; Treatment Failure ; Tumor Burden*