Radiation Therapy Oncology Group 8502 "QUAD shot" regimen using volumetric modulated arc therapy for incurable head and neck cancer

OBJECTIVES

We aimed to evaluate the outcomes of the Radiation Therapy Oncology Group 8502 "QUAD shot" regimen using volumetric modulated arc therapy (VMAT) for incurable head and neck cancer (HNC).

MATERIALS AND METHODS

We included 105 patients with HNC in the study, undergoing at least one QUAD shot regimen cycle. We planned the radiotherapy using VMAT with 6 MV photons. One QUAD shot cycle included 14.8 Gy in 4 fractions with at least 6-hour intervals over 2 consecutive days, repeated every 3-6 weeks up to 3 cycles.

RESULTS

We completed 1, 2, and 3 cycles in 11 (10 %), 17 (16 %), and 77 (73 %) patients, respectively. We concurrently performed systemic therapy in 13 (12 %) patients. Tumor response was observed in 92 (88 %) patients and at least one symptom relief in 51 (71 %) of 72 patients. We observed an overall response (tumor response or symptom relief) in 98 (93 %) patients with all patients who completed 3 cycles achieving it. The median overall survival (OS) was 6.8 months. Our multivariate analysis revealed that non-squamous cell carcinoma (p < 0.001), T category of 0-2 (p = 0.021), and 3 QUAD shot cycles (p < 0.001) were independent prognostic factors of better OS. We observed Grade 3 toxicity in 2 (2 %) patients while no ≥ Grade 4 acute or ≥ Grade 3 late toxicity.

CONCLUSIONS

The QUAD shot regimen using VMAT exerts appropriate palliative effect in patients with incurable HNC. Treatment with higher QUAD shot cycle number would be recommended for better treatment outcomes.

Postoperative disappearance of leptomeningeal enhancement around the brainstem in glioblastoma

PURPOSE

Leptomeningeal enhancement (LME) suggests leptomeningeal dissemination (LMD) of tumor cells, which is a complication of end-stage glioblastoma, and is associated with a poor prognosis. However, magnetic resonance imaging (MRI) occasionally indicates the disappearance of peri-brainstem LME after surgical resection of glioblastoma. Since preoperative LMD may affect treatment indications, we aimed to analyze the clinical significance of preoperative LME of the brainstem in glioblastoma.

METHODS

We retrospectively collected clinical and radiological data from consecutive patients with glioblastoma and preoperative LME of the brainstem, who were treated at our hospital between 2017 and 2020.

RESULTS

Among 112 patients with glioblastoma, nine (8%) showed preoperative LME of the brainstem. In comparison with tumors without LME, tumor size was significantly associated with the preoperative LME of the brainstem (p = 0.016). In addition, there was a trend toward significance for a relationship between deep tumor location and preoperative LME of the brainstem (p = 0.058). Notably, among six patients who underwent surgical resection for glioblastoma with LME of the brainstem, four showed significant radiological disappearance of the LME on postoperative MRI. This suggests that the LME did not result from LMD in these cases. Moreover, these four patients lived longer than would be expected from the presence of LMD. However, this LME disappearance was not observed after biopsy or chemoradiotherapy.

CONCLUSIONS

These findings suggest that preoperative LME does not necessarily indicate the presence of untreatable LMD; moreover, LME may disappear after surgical tumor resection. Thus, transient preoperative LME could be attributed to other mechanisms, including impaired venous flow due to intratumoral arteriovenous shunts, which can be resolved by reducing the tumor burden.

Re-irradiation for isolated neck recurrence in head and neck tumor: impact of rN category

Unresectable, isolated lymph node recurrence after radiotherapy is rare but a candidate for re-irradiation. However, severe toxicity is anticipated. Therefore, this study aimed to explore the efficacy and toxicity of re-irradiation in isolated lymph node recurrence of head and neck lesions. We analyzed 46 patients who received re-irradiation for lymph node recurrence without local progression. The primary tumor sites included the oral cavity in 17 patients, the hypopharynx in 12, the oropharynx in seven, the larynx in three, the nasopharynx in two, and other sites. During a median follow-up time of 10 months, the median survival time was 10.6 months, and the 1-year overall survival rate was 45.5%. The 1-year local control and progression-free survival rates were 49.8% and 39.3%, respectively. According to univariate analysis, age (≥ 65 years), the interval between treatment (≥ 12 months), rN category (rN1), and gross tumor volume (GTV < 25 cm3) were predisposing factors for better survival. In the multivariate analysis, the rN category and interval were identified as statistically significant predictors. Late toxicity grade ≥ 3 occurred in four patients (8.6%). These were all Grade 5 carotid blowout syndrome, which associated with tumor invasion of the carotid artery and/ or high doses administration for the carotid artery. Small-volume rN1 tumor that recur after a longer interval is a feasible candidate for re-irradiation. However, strict patient selection and meticulous care for the carotid are required.

Influence of Respiratory Motion on Dose Distribution in Gastric Mucosa-associated Lymphoid Tissue Lymphoma Radiotherapy

BACKGROUND/AIM

The present study investigated the effect of respiratory motion on planned radiotherapy (RT) dose for gastric mucosa-associated lymphoid tissue (MALT) lymphoma using four-dimensional dose (4D-dose) accumulation.

PATIENTS AND METHODS

4D-computed tomography (4D-CT) images of 10 patients with gastric MALT lymphomas were divided into 10 respiratory phases. Further, the 3D-dose was calculated using 3D conformal RT (3D-CRT) and volumetric modulated arc therapy (VMAT) plans based on the average intensity projection (AIP) images. Then, both plans were recalculated according to each phase image. Moreover, the dose distributions in each phase were transferred to the AIP images using deformable image registration. The 4D-dose distribution was calculated by summing the doses of each phase, and it was compared with the dosimetric parameters of the 3D-dose distribution.

RESULTS

For 3D-CRT, the D95 and D99 of the 4D-dose in the planning target volume (PTV) were significantly lower than those of the 3D-dose, with mean differences of 0.2 (p=0.009) and 0.1 Gy (p=0.021), respectively. There were no significant differences in the other PTV and organ-at-risk dosimetric parameters of 3D-CRT or in any dosimetric parameters of VMAT between the 3D- and 4D-dose distributions.

CONCLUSION

The effect of respiratory motion on the planned 3D-CRT and VMAT dose distributions for gastric MALT lymphoma is minimal and clinically negligible.

Superconducting nonlinear transport in optically driven high-temperature K3C60

Optically driven quantum materials exhibit a variety of non-equilibrium functional phenomena, which to date have been primarily studied with ultrafast optical, X-Ray and photo-emission spectroscopy. However, little has been done to characterize their transient electrical responses, which are directly associated with the functionality of these materials. Especially interesting are linear and nonlinear current-voltage characteristics at frequencies below 1 THz, which are not easily measured at picosecond temporal resolution. Here, we report on ultrafast transport measurements in photo-excited K3C60. Thin films of this compound were connected to photo-conductive switches with co-planar waveguides. We observe characteristic nonlinear current-voltage responses, which in these films point to photo-induced granular superconductivity. Although these dynamics are not necessarily identical to those reported for the powder samples studied so far, they provide valuable new information on the nature of the light-induced superconducting-like state above equilibrium Tc. Furthermore, integration of non-equilibrium superconductivity into optoelectronic platforms may lead to integration in high-speed devices based on this effect.

Prevalence and Risk Factors for Retropharyngeal and Retro-Styloid Lymph Node Metastasis in Hypopharyngeal Carcinoma

PURPOSE/OBJECTIVE(S)

We evaluated the prevalence and identified the risk factors for retropharyngeal and retro-styloid lymph node metastasis (LNM) in patients with hypopharyngeal carcinoma (HPC). This was achieved using a combination of MR and FDG-PET/CT images.

MATERIALS/METHODS

Two board-certified radiation oncologists, who experienced 16 and 18 years in the diagnosis and treatment of head and neck cancers retrospectively reviewed pretreatment FDG-PET/CT images and contrast-enhanced thin-slice CT and MR images of 155 patients with HPC who underwent radiotherapy. Observers assessed these images without prior knowledge of the patient's clinical information and disagreements were resolved by consensus. The radiological diagnostic criteria for lateral retropharyngeal LNM (RPLNM) and retro-styloid LNM (RSLNM) were a short-axis diameter of ≥5 mm and/or necrosis and/or abnormal FDG uptake. Any visible medial RPLN was defined as LNM.

RESULTS

RPLNM was confirmed in 20 (13%) patients. Of these, 10 (6%) had ipsilateral RPLNM, 5 (3%) had contralateral RPLNM, and 5 (3%) had bilateral RPLNM. No patients were diagnosed with medial RPLNM. Fisher's exact test revealed tumor site (p = 0.006), T category (p = 0.049), and cervical LNM (p < 0.001) to be significantly associated with RPLNM. Logistic regression analysis revealed posterior wall (PW) tumors (odds ratio [OR]: 4.128, 95% confidence interval [CI]: 1.339-12.727; p = 0.014) and bilateral or contralateral cervical LNM (OR: 11.577, 95% CI: 2.135-62.789; p = 0.005) to be significantly correlated with RPLNM. The RPLNM was found in 9 (32%) of the 28 patients with PW tumors. Of these 9 patients, 2 (7%) had ipsilateral RPLNM, 3 (11%) had contralateral RPLNM, and 4 (14%) had bilateral RPLNM. Fisher's exact test revealed the PW tumors to be significantly associated with contralateral RPLNM (p < 0.001). Retro-styloid LNM (RSLNM) was confirmed in two (1%) patients, both of whom had ipsilateral RSLNM with lymph nodes (LNs) of ≥15 mm in the upper limit of ipsilateral level II. Fisher's exact test revealed the LN of ≥15 mm in the upper limit of ipsilateral level II to be significantly associated with ipsilateral RSLNM (p = 0.001).

CONCLUSION

The RPLNM was identified in 13% of patients with HPC. The PW tumors and bilateral or contralateral cervical LNM were risk factors for RPLNM; particularly, PW tumors were a specific risk factor for contralateral RPLNM. Although the RSLNM was rare, LNs of ≥15 mm in the upper limit of ipsilateral level II were a risk factor for ipsilateral RSLNM.

Prevalence and risk factors for retropharyngeal and retro-styloid lymph node metastasis in hypopharyngeal carcinoma

BACKGROUND

We evaluated the prevalence and identified the risk factors for retropharyngeal and retro-styloid lymph node metastasis (LNM) in patients with hypopharyngeal carcinoma (HPC). This was achieved using a combination of magnetic resonance (MR) and [18 F]-fluoro-2-deoxy-D-glucose (FDG)-positron emission tomography (PET)/computed tomography (CT) images.

METHODS

Two board-certified radiation oncologists retrospectively reviewed pretreatment FDG-PET/CT images and contrast-enhanced thin-slice CT and MR images of 155 patients with HPC who underwent radiotherapy. Fisher's exact tests and logistic regression analyses were performed to assess the risk factors for LNM.

RESULTS

Retropharyngeal LNM (RPLNM) was confirmed in 20 (13%) patients. Posterior wall (PW) tumors (odds ratio [OR]: 4.128, 95% confidence interval [CI]: 1.339-12.727; p = 0.014) and bilateral or contralateral cervical LNM (OR: 11.577, 95% CI: 2.135-62.789; p = 0.005) were significantly correlated with RPLNM. The RPLNM was found in 9 (32%) of the 28 patients with PW tumors. Of these 9 patients, 2 (7%) had ipsilateral RPLNM, 3 (11%) had contralateral RPLNM, and 4 (14%) had bilateral RPLNM. The PW tumors were significantly associated with contralateral RPLNM (p < 0.001). Retro-styloid LNM (RSLNM) was confirmed in two (1%) patients, both of whom had ipsilateral RSLNM with lymph nodes (LNs) of ≥ 15 mm in the upper limit of ipsilateral level II. A significant association was found between LNs of ≥ 15 mm in the upper limit of ipsilateral level II and ipsilateral RSLNM (p = 0.001).

CONCLUSIONS

The RPLNM was identified in 13% of patients with HPC. The PW tumors and bilateral or contralateral cervical LNM were risk factors for RPLNM; particularly, PW tumors were a specific risk factor for contralateral RPLNM. Although the RSLNM was rare, LNs of ≥ 15 mm in the upper limit of ipsilateral level II were a risk factor for ipsilateral RSLNM.

Prevalence and risk factors of retro-styloid lymph node metastasis in oropharyngeal carcinoma

BACKGROUND

Supporting data defining the selection criteria of level VIIb for inclusion in the target volume in radiotherapy (RT) planning are insufficient. We evaluated the prevalence of level VIIb retro-styloid lymph node metastasis (RSLNM) and associated risk factors in patients with oropharyngeal carcinoma (OPC).

MATERIALS AND METHODS

We retrospectively reviewed pre-treatment [¹⁸F]-fluoro-2-deoxy-d-glucose-positron emission tomography/computed tomography (CT) along with contrast-enhanced thin slice CT and magnetic resonance (MR) images of 137 patients pathologically confirmed as having OPC who underwent RT. The location of lymph nodes (LNs) was confirmed on the planning CT images. Fisher's exact test and logistic regression analyses were made to determine the risk factors of RSLNM.

RESULTS

RSLNM was confirmed in 18 (13%) patients. All RSLNMs were located within level VIIb on the planning CT images. No patients exhibited LNM in contralateral level VIIb. Furthermore, no patients with negative or single ipsilateral cervical LNM had RSLNM. Fisher's exact test revealed that smoking status (p=.027), multiple ipsilateral cervical LNM (p=.045) and LN ≥15 mm in the upper limit of ipsilateral level II (p<.001) were significantly associated with RSLNM. Logistic regression analyses revealed that the presence of LNs ≥15 mm in upper limit of ipsilateral level II was significantly associated with RSLNM (odds ratio: 977.297; 95% confidence interval: 57.629-16573.308; p<.001).

CONCLUSIONS

RSLNM is relatively common in patients with OPC with a prevalence rate of approximately 10%. The prevalence of RSLNM in patients with negative or single ipsilateral cervical LNM and contralateral RSLNM is extremely low; therefore, level VIIb can be excluded from the target volume in such patients. LN ≥15 mm in the upper limit of ipsilateral level II is a risk factor for RSLNM. Ipsilateral level VIIb should be included in the target volume for patients with this risk factor.KEY MESSAGERetro-styloid lymph node metastasis (RSLNM) prevalence is ∼10% in oropharyngeal carcinoma.Lymph node ≥15 mm in ipsilateral level II upper limit is a risk factor for RSLNM.

Reduced-dose WBRT combined with SRS for 1–4 brain metastases aiming at minimizing neurocognitive function deterioration without compromising brain tumor control

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The addition of whole-brain radiotherapy (WBRT) to stereotactic radiosurgery (SRS) reduces the risk of brain tumor recurrence but standard-dose WBRT (SD-WBRT) accompanies the risk of neurocognitive decline.

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Reduced-dose WBRT (RD-WBRT) combined with SRS provides intracranial tumor control rate comparable to that after SD-WBRT + SRS.

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RD-WBRT could reduce the risk of neurocognitive decline compared to that after SD-WBRT.

Background and purpose

To minimize cognitive decline without increasing brain tumor recurrence (BTR) by reduced-dose whole-brain radiotherapy (RD-WBRT) (25 Gy, 10 fractions) + stereotactic radiosurgery (SRS) in patients with ≤ 4 brain metastases.

Materials and methods

Eligible patients with ≤ 4 brain metastases on contrast-enhanced MRI and Karnofsky Performance Status ≥ 70. The primary endpoint was the non-inferiority of BTR at distant sites in the brain (BTR-distant)-free survival at 6 months compared to that of the standard dose (SD)-WBRT (30 Gy, 10 fractions) + SRS arm in a randomized clinical trial (JROSG99-1) of SRS with/without SD-WBRT. Secondary endpoints included BTR at any brain sites (BTR-all) and neurocognitive function assessed by a six-test standardized battery.

Results

Forty patients from seven institutions were enrolled (median age 69 years). The primary tumor site was a lung in 28 patients; 20 patients had a solitary brain metastasis. The median survival time was 19.0 months (95 %CI: 13.8 %–27.5 %). The BTR-distant-free survival at 6 months was 76.9 % (59.5 %–87.7 %), which is comparable to that of historical control although predetermined non-inferiority (>71 %) could not be confirmed (p = 0.16). The cumulative incidence of BTR-all at 6 months accounting for the competing risk of death was 23.0 % (11.4–37.1), which was not worse than that of historical control (p = 0.774). The frequency of the cumulative incidence of persistent cognitive decline at 6 months was 48.6 % under the [>2.0 SD in ≥ 1 test] definition.

Conclusions

RD-WBRT may yield comparable intracranial tumor control when combined with SRS, and may reduce the risk of neurocognitive decline compared to that after SD-WBRT.

Impact of metal artifact reduction algorithm on gross tumor volume delineation in tonsillar cancer: reducing the interobserver variation

Background

Patients with tonsillar cancer (TC) often have dental fillings that can significantly degrade the quality of computed tomography (CT) simulator images due to metal artifacts. We evaluated whether the use of the metal artifact reduction (MAR) algorithm reduced the interobserver variation in delineating gross tumor volume (GTV) of TC.

Methods

Eighteen patients with TC with dental fillings were enrolled in this study. Contrast-enhanced CT simulator images were reconstructed using the conventional (CT_CONV) and MAR algorithm (CT_MAR). Four board-certified radiation oncologists delineated the GTV of primary tumors using routine clinical data first on CT_CONV image datasets (GTV_CONV), followed by CT_CONV and CT_MAR fused image datasets (GTV_MAR) at least 2 weeks apart. Intermodality differences in GTV values and Dice similarity coefficient (DSC) were compared using Wilcoxon’s signed-rank test.

Results

GTV_MAR was significantly smaller than GTV_CONV for three observers. The other observer showed no significant difference between GTV_CONV and GTV_MAR values. For all four observers, the mean GTV_CONV and GTV_MAR values were 14.0 (standard deviation [SD]: 7.4) cm³ and 12.1 (SD: 6.4) cm³, respectively, with the latter significantly lower than the former (p < 0.001). The mean DSC of GTV_CONV and GTV_MAR was 0.74 (SD: 0.10) and 0.77 (SD: 0.10), respectively, with the latter significantly higher than that of the former (p < 0.001).

Conclusions

The use of the MAR algorithm led to the delineation of smaller GTVs and reduced interobserver variations in delineating GTV of the primary tumors in patients with TC.

Implementation of 99mTc-GSA SPECT Image-guided Inverse Planning into Palliative Radiotherapy for Diffuse Liver Metastases: A Novel Approach

BACKGROUND/AIM

This is a report of the first clinical implementation of ^99mTc-labeled diethylene triamine pentaacetate-galactosyl human serum albumin (^99mTc-GSA) single-photon emission computed tomography (SPECT) image-guided inverse planning into palliative radiotherapy (RT) for diffuse liver metastases.

CASE REPORT

A 48-year-old man developed chemo-refractory diffuse liver metastases from thymic carcinoma characterized by abdominal pain and distension. Palliative RT was performed with a total dose of 20 Gy in five fractions using double arc volumetric modulated arc therapy to reduce the dose to functional liver defined by ^99mTc-GSA SPECT images. His symptoms were immediately relieved after RT and did not experience radiation-induced liver disease. Both Functional Assessment of Cancer Therapy (FACT)-G and FACT-Hep total scores improved after 2 weeks of RT initiation and did not become worse than baseline scores.

CONCLUSION

The ^99mTc-GSA SPECT image-guided palliative RT is an effective and safe treatment for patients with diffuse liver metastases.

A prospective comparison of adaptive and fixed boost plans in radiotherapy for glioblastoma

Purpose

To analyze the efficacy of adaptive radiotherapy (ART) for glioblastoma.

Methods

Sixty-one glioblastoma patients who received ART were prospectively evaluated. The initial clinical target volume (CTVinitial) was represented by T2 hyperintensity on postoperative MRIs (pre-RT MRI [MRIpre])plus 10 mm. The initial planning target volume (PTVinitial) was the CTVinitial plus a 5-mm margin. The PTVinitial received 40 Gy. An MRI and a second planning CT were performed during radiotherapy (MRImid). Two types of boost CTVs (the resection cavity and residual tumor on enhanced T1-weighted MRI plus 10 mm) were created based on the MRIpre and MRImid (CTVboost-pre and -mid). The boost PTV (PTVboost) was the CTVboost plus 5 mm. Two types of boost plans (fixed and adaptive boost plans in the first and second planning CT, respectively) of 20 Gy were created. The PTV based on the post-RT MRI (PTVboost-post) was created, and the dose-volume histograms of the PTVboost-post in the fixed and adaptive boost plans were compared. Additionally, the conformity indices (CIs) of the fixed and adaptive boost plans were compared.

Results

The median V95 of the PTVboost-post of the fixed and adaptive boost plans (V95pre and V95mid) were 95.6% and 98.3%, respectively (P < 0.01). The median V95pre and V95mid of patients after gross total resection (GTR) were 97.4% and 98.8%, respectively (P = 0.41); in contrast, the median values of patients after non-GTR were 91.9% and 98.2%, respectively (P < 0.01). The median CIs of the fixed and adaptive boost plans in all patients were 1.45 and 1.47, respectively (P = 0.31). The median CIs of the fixed and adaptive boost plans in patients after GTR were 1.61 and 1.48, respectively (P = 0.01); in contrast, those in patients after non-GTR were 1.36 and 1.44, respectively (P = 0.13).

Conclusion

ART for glioblastoma improved the target coverage and dose reduction for the normal brain. By analyzing the results according to the resection rate, we can expect a decrease in normal brain dose in patients with GTR and an increase in coverage in those with partial resection or biopsy.

Concurrent Chemoradiotherapy With Docetaxel, Cisplatin, and 5-Fluorouracil for T3 N0 Glottic Carcinoma Without Vocal Cord Fixation

BACKGROUND/AIM

We retrospectively evaluated the efficacy and toxicity of concurrent chemoradiotherapy (CCRT) with docetaxel, cisplatin, and 5-fluorouracil (TPF) for T3 N0 glottic carcinoma without vocal cord fixation.

PATIENTS AND METHODS

Twenty-five patients underwent TPF-CCRT without elective nodal irradiaion (ENI). After the RT of 40 Gy, five patients (20%) without tumor regression underwent surgery. Others underwent RT with a median total dose of 66 Gy.

RESULTS

Of the five patients who underwent surgery after the RT of 40 Gy, two showed residual carcinoma pathologically and the other three were confirmed to have complete pathological response to the treatment. The 5-year local control rate was 87%. No patients exhibited regional failure. No acute toxicities of grade 5 or late toxicities ≥grade 3 were observed.

CONCLUSION

TPF-CCRT provides excellent tumor control with acceptable toxicities. CCRT while omitting ENI is a reasonable approach for T3 N0 glottic carcinoma without vocal cord fixation.

Palliative radiotherapy for painful lymph node metastases

BACKGROUND

There is limited evidence concerning radiotherapy for painful lymph node metastases (PLM). We evaluated the effectiveness of radiotherapy for PLM using the International Consensus Endpoint in a subgroup analysis of a prospective observational study.

METHODS

In the primary study, 302 patients received radiotherapy for painful tumors. Among them, those treated with palliative radiotherapy for PLM were analyzed in the present study. We used the Brief Pain Inventory short form to evaluate the intensity of pain and the pain interference in patient's life. We collected the Brief Pain Inventory and analgesic data at baseline and at 1, 2, and 3 months after the start of radiotherapy. Pain response was assessed using the International Consensus Endpoint. Patients were diagnosed with a predominance of other pain (POP) if non-index pain of a malignant or unknown origin was present and had a greater 'worst pain' score than the index pain.

RESULTS

Radiotherapy for PLM was performed on 25 patients. In total, 15 (60%) patients experienced a pain response. The pain response rates for evaluable patients were 66%, 67%, and 57% at 1-, 2-, and 3-month follow-ups, respectively. At baseline and at 1, 2, and 3 months, the median index pain scores were 7, 2, 0, and 0.5, respectively. At 1 month, all pain interference scores were significantly reduced from baseline. Four (16%) patients experienced POP within three months.

CONCLUSION

Radiotherapy for PLM improved pain intensity and pain interference. Palliative radiotherapy may be a viable treatment option for PLM.

Outcomes of robot-assisted versus conventional laparoscopic low anterior resection in patients with rectal cancer: propensity-matched analysis of the National Clinical Database in Japan

BACKGROUND

Robot-assisted laparoscopic surgery has several advantages over conventional laparoscopy. However, population-based comparative studies for low anterior resection are limited. This article aimed to compare peri-operative results of robot-assisted low anterior resection (RALAR) and laparoscopy.

METHODS

This retrospective cohort study used data from patients treated with RALAR or conventional laparoscopic low anterior resection (CLLAR) between October 2018 and December 2019, as recorded in the Japanese National Clinical Database, a data set registering clinical information, perioperative outcomes, and mortality. Of note, the registry does not include information on the tumour location (centimetres from the anal verge) and diverting stoma creation. Perioperative outcomes, including rate of conversion to open surgery, were compared between RALAR and CLLAR groups. Confounding factors were adjusted for using propensity score matching.

RESULTS

Of 21 415 patients treated during the study interval, 20 220 were reviewed. Two homogeneous groups of 2843 patients were created by propensity score matching. The conversion rate to open surgery was significantly lower in the RALAR group than in the CLLAR group (0.7 versus 2.0 per cent; P < 0.001). The RALAR group had a longer operating time (median: 352 versus 283 min; P < 0.001), less intraoperative blood loss (15 versus 20 ml; P < 0.001), a lower in-hospital mortality rate (0.1 versus 0.5 per cent; P = 0.007), and a shorter postoperative hospital stay (median: 13 versus 14 days; P < 0.001) compared with the CLLAR group. The CLLAR group had a lower rate of readmission within 30 days (2.4 versus 3.3 per cent; P = 0.045).

CONCLUSION

These data highlight the reduced conversion rate, in-hospital mortality rate, intraoperative blood loss, and length of postoperative hospital stay for rectal cancer surgery in patients treated using robot-assisted laparoscopic surgery compared with laparoscopic low anterior resection.

Plan Quality Comparisons Between 3D-CRT, IMRT, and VMAT Based on 4D-CT for Gastric MALT Lymphoma

BACKGROUND/AIM

We compared three-dimensional conformal RT (3D-CRT), intensity-modulated radiotherapy (IMRT), and volumetric modulated arc therapy (VMAT) for gastric mucosa-associated lymphoid tissue (MALT) lymphoma using four-dimensional computed tomography (4D-CT) images.

PATIENTS AND METHODS

Three treatment plans of 3D-CRT, IMRT, and VMAT with 30 Gy were created based on 4D-CT images of seven patients. We calculated D95, homogeneity index (HI), and conformity index (CI) of planning target volume, and organs at risk doses.

RESULTS

There was no significant difference among the three plans in D95. HI of the IMRT plan was significantly better than that of the VMAT (p=0.047) and 3D-CRT (p=0.047) plans. CIs of the IMRT and VMAT plans were significantly better than those of the 3D-CRT plan (p=0.047 and p=0.047, respectively). D_mean of the liver for 3D-CRT was significantly higher than that for the IMRT (p=0.047) and VMAT (p=0.047) plans.

CONCLUSION

The IMRT plan yields the best plan quality for gastric MALT lymphoma.

Effects of polypharmacy on the prevalence of adverse drug events resulting in outpatient visits and hospitalization

A high proportion of hospitalizations is attributable to the prevalence of adverse drug events. This retrospective study included outpatients and inpatients to determine the prevalence of adverse drug events and if polypharmacy increases it. The prevalence, classification, and causality of adverse drug events were assessed based on medical records, laboratory values, and other data. Multivariate analysis (multiple logistic regression analysis) was performed with the presence or absence of adverse drug events at the time of the visit as the dependent variable and items for which the P-value was <0.25 in the univariate analysis as independent variables. The prevalence of adverse drug events was 13.0%, 10.9%, and 16.0% among all patients, the outpatient group, and the inpatient group, respectively. Multivariate analysis showed that polypharmacy (≥5 drugs) significantly increased the risk of adverse drug events in all patients. The prevalence of adverse drug events significantly increased with each additional drug used. We expect that minimizing the number of medications through moderation of the number of prescription drugs and elimination of polypharmacy will reduce the number of outpatient visits and hospitalizations due to adverse drug events.

Stereotactic Body Radiotherapy Based on 99mTc-GSA SPECT Image-guided Inverse Planning for Hepatocellular Carcinoma

BACKGROUND/AIM

A recent planning study suggested that ^99mTc-labelled diethylene triamine pentaacetate-galactosyl human serum albumin (^99mTc-GSA) single-photon emission computed tomography (SPECT) image-guided inverse planning (IGIP) shows dosimetric superiority to conventional planning in sparing liver function. Here, we report the first clinical translation of ^99mTc-GSA SPECT IGIP for stereotactic body radiotherapy (SBRT) in a patient with hepatocellular carcinoma (HCC).

CASE REPORT

A 60-year-old male developed obstructive jaundice caused by recurrent HCC in segment 1 after hepatic resection. He underwent repeated radiotherapy (RT) consisting of 45 Gy in 15 fractions 8 years ago and 30 Gy in 5 fractions 2 years ago. We performed SBRT consisting of 40 Gy in 8 fractions using ^99mTc-GSA SPECT-IGIP. We confirmed the dosimetric superiority of functional IGIP to conventional planning. He achieved complete response as assessed using the target volume. The patient has remained alive without recurrence for 18 months. He did not experience radiation-induced liver disease.

CONCLUSION

Recurrent HCC was successfully and safely salvaged via re-irradiation with SBRT using ^99mTc-GSA SPECT-IGIP.

QUAD shot: an effective cyclical hypofractionated palliative radiotherapy for salivary gland carcinoma

Surgery with or without post-operative radiotherapy is the mainstay treatment for salivary gland carcinoma (SGC); however, palliative radiotherapy or supportive observation is considered for elderly patients. An 87-year-old female who was diagnosed with SGC in the left parotid gland, with a clinical stage T4aN2bM0 Stage IVA, underwent the Radiation Therapy Oncology Group 8502 “QUAD shot” regimen (14.8 Gy/4 fractions, twice-daily treatment with a 6 h interval, on 2 consecutive days), which were repeated every 4 weeks 3 times using volumetric modulated arc therapy. During and after the treatment, she experienced no acute toxicity but had Grade 1 xerostomia. At 4 months after completion of the treatment, [¹⁸F]-fluoro-2-deoxy-D-glucose positron emission tomography/CT revealed a complete metabolic response to the treatment. She is still alive without any evidence of recurrence 9 months after completion of the treatment. The Radiation Therapy Oncology Group 8502 “QUAD shot” regimen using VMAT may be an effective palliative treatment for SGC with minimal toxicity.

Hypofractionated palliative volumetric modulated arc radiotherapy with the Radiation Oncology Study Group 8502 "QUAD shot" regimen for incurable head and neck cancer

BACKGROUND

To review a single institutional experience of the Radiation Therapy Oncology Group (RTOG) 8502 "QUAD shot" regimen using volumetric modulated arc radiotherapy (VMAT) for incurable head and neck cancer (HNC).

METHODS

Thirty-four consecutive patients with HNC were treated with at least one cycle of the RTOG 8502 regimen. Treatment plans included the use of VMAT with 6 MV photons generated by a linear accelerator. Two daily fractions of 3.7 Gy were delivered with an interval of at least 6 h for 2 consecutive days, totaling 14.8 Gy over 4 fractions. This was repeated every 3-4 weeks for a total of three cycles. No concurrent systemic therapy was performed.

RESULTS

The number of completed cycles was 1 in 6 (18%) patients, 2 in 5 (15%), and 3 in 23 (68%). Tumor response was achieved in 29 (85%) patients and symptom relief in 20 (77%) of 26 patients. Overall response (tumor response or symptom relief) was achieved in 32 (94%) patients. All patients who received 2 or more treatment cycles achieved overall response. Median overall survival (OS) was 5.7 months. Multivariate analysis revealed that completion of all three treatment cycles was significantly associated with better OS (P = 0.002). Grade 2 toxicity was observed in four (12%) patients, but no acute Grade ≥ 3 or late toxicity was observed.

CONCLUSIONS

The RTOG 8502 "QUAD shot" regimen using VMAT is effective for incurable HNC with highly reduced toxicity. Treatment with multiple cycles is recommended for better treatment response and/or survival.

High Spatial Resolution Digital Positron Emission Tomography Images With Dedicated Source-to-background Algorithm for Radiotherapy Planning

BACKGROUND/AIM

To evaluate the utility of high spatial resolution digital positron emission tomography images with the source-to-background ratio (SBR) algorithm for gross tumour volume (GTV) delineation.

MATERIALS AND METHODS

The bowl and spheres (10-37 mm) were filled with fluoro-2-deoxy-D-glucose to achieve 4-16 times background radioactivity. The images were reconstructed using three isotropic voxel sizes. The SBR and percentage threshold (TH) to SUV_max were calculated. The plots between SBR and TH were fitted using a regression equation. The contoured volumes (CVs) of the spheres were calculated by applying TH.

RESULTS

TH was 38.6+75.0/SBR for 4 mm voxel size; 39.6+37.0/SBR for 2 mm; and 38.8+35.2/SBR for 1 mm. The mean relative errors between CV and true volume for 4, 2, and 1 mm voxel sizes were 15%, 7%, and 7%, respectively.

CONCLUSION

The present technique is useful for GTV delineation with reduced contouring error.

Diagnostic Value of FDG-PET/CT for the Identification of Extranodal Extension in Patients With Head and Neck Squamous Cell Carcinoma

BACKGROUND/AIM

We evaluated the diagnostic value of functional imaging with [¹⁸F]-fluoro-2-deoxy-D-glucose (FDG)-positron emission tomography/computed tomography (PET/CT) for the identification of extranodal extension (ENE) in patients with head and neck squamous cell carcinoma (HNSCC).

PATIENTS AND METHODS

In this study, 94 patients with HNSCC who underwent FDG-PET/CT were enrolled. We recorded the maximum standardized uptake value (SUV_max), compared the results with pathologic findings, and evaluated the diagnostic performance of using a SUV_max cut-off value for ENE.

RESULTS

Of the 566 dissected levels examined, 53 (9.4%) exhibited ENE. The mean SUV_max of LN with and without ENE were 6.67 and 1.64, respectively (p<0.001). A receiver operating characteristics (ROC) curve analysis for SUV_max showed an area under the ROC curve of 0.913. A SUV_max cut-off of 3.0 achieved diagnostic performance for identifying ENE with sensitivity, specificity, and accuracy of 81.1%, 94.3% and 93.1%, respectively.

CONCLUSION

FDG-PET/CT findings using a SUV_max cut-off of 3.0 provides appropriate diagnostic value in identifying ENE.

Association between dipeptidyl peptidase-4 inhibitors and autoimmune disorders: Data mining of the spontaneous reporting system in Japan

The main objective of this study is to conduct a disproportionality analysis of adverse events in the Japan Adverse Event Report (JADER) database and evaluate the risk of the DPP-4 inhibitor induced autoimmune disorder, the secondary objective is risk assessment of sex difference and age difference. The proportional reporting ratio (PRR) of frequency-based statistics and Bayesian estimates of the information components (IC) were calculated as a measure of signal detection. Sex difference and age difference were evaluated using signal score calculated from the PRR and the Chi-square. In patients taking DPP-4 inhibitors, 94 reports of autoimmune disorders were detected with both signals; PRR: 4.09, chi-square: 158.26 and IC: 1.66, 95 % confidence interval: 1.32-2.00). For other antidiabetic drugs, no signals were detected. The signal of males was PRR: 4.53, chi-square: 110.91 and signal score: 6.22, the signal of female was PRR: 3.53, chi-square: 47.65 and signal score: 5.12. About age difference, the signal scores were 6.71 for patients over 60 years and 0.56 for patients under 60 years old. This study suggests that the DPP-4 inhibitors, unlike other antidiabetic drugs, were associated with autoimmune disorders. Signals of the DPP-4 inhibitors induced autoimmune disorders were detected in both male and female, but no sex difference was observed, but age difference was observed. Especially attention should be paid to patients over 60 years old.

Light-induced anomalous Hall effect in graphene

Many non-equilibrium phenomena have been discovered or predicted in optically-driven quantum solids¹. Examples include light-induced superconductivity^2,3 and Floquet-engineered topological phases^4-8. These are short lived effects that should lead to measurable changes in electrical transport, which can be characterized using an ultrafast device architecture based on photoconductive switches⁹. Here, we report the observation of a light-induced anomalous Hall effect in monolayer graphene driven by a femtosecond pulse of circularly polarized light. The dependence of the effect on a gate potential used to tune the Fermi level reveals multiple features that reflect a Floquet-engineered topological band structure^4,5, similar to the band structure originally proposed by Haldane¹⁰. This includes an approximately 60 meV wide conductance plateau centered at the Dirac point, where a gap of equal magnitude is predicted to open. We find that when the Fermi level lies within this plateau, the estimated anomalous Hall conductance saturates around 1.8±0.4 e²/h.

Graft Immunocomplex Capture Fluorescence Analysis Can Detect Intragraft Anti-Major Histocompatibility Complex Antibodies in Mice Cardiac Transplant

BACKGROUND

Immunocomplex capture fluorescence analysis has recently been applied as a method for detection of intragraft donor-specific anti-major histocompatibility complex (MHC) antibodies (DSA) in humans. Although intragraft DSA in humans is an intense topic of investigation, there is no report to assess intragraft DSA in murine organ transplantation.

METHODS

A model of presensitized mouse cardiac transplantation by donor splenocytes was used. To capture mouse MHC, anti-MHC class I/II antibodies were immobilized on Luminex beads. The MHC/DSA complexes were captured by the Luminex beads followed by detection of phycoerythrin-conjugated antimouse IgG antibodies where DSA had already reacted with the allograft in vivo.

RESULTS

Luminex beads were capable of detecting class I DSA in the cardiac allograft, though results for class II DSA were negative. Immunohistochemical investigation revealed that cardiac allografts had abundant MHC class I expression but only minor expression of MHC class II. Furthermore, MHC/class II DSA complexes were successfully detected in splenocytes and serum from a presensitized recipient.

CONCLUSIONS

These data suggested that graft immunocomplex capture fluorescence analysis can be also applied in murine cardiac transplantation. This novel application in mice would accelerate our comprehension of DSA through mechanistic studies.

Impact of hybrid FDG-PET/CT on gross tumor volume definition of cervical esophageal cancer: reducing interobserver variation

Intensity-modulated radiation therapy is being increasingly used to treat cervical esophageal cancer (CEC); however, delineating the gross tumor volume (GTV) accurately is essential for its successful treatment. The use of computed tomography (CT) images to determine the GTV produces a large degree of interobserver variation. In this study, we evaluated whether the use of [18F]-fluoro-2-deoxy-D-glucose positron emission tomography (FDG-PET)/CT fused images reduced interobserver variation, compared with CT images alone, to determine the GTV in patients with CEC. FDG-PET/CT scans were obtained for 10 patients with CEC, imaged positioned on a flat tabletop with a pillow. Five radiation oncologists independently defined the GTV for the primary tumors using routine clinical data; they contoured the GTV based on CT images (GTVCT), followed by contouring based on FDG-PET/CT fused images (GTVPET/CT). To determine the geometric observer variation, we calculated the conformality index (CI) from the ratio of the intersection of the GTVs to their union. The interobserver CI was compared using Wilcoxon's signed rank test. The mean (±SD) interobserver CIs of GTVCT and GTVPET/CT were 0.39 ± 0.15 and 0.58 ± 0.10, respectively (P = 0.005). Our results suggested that FDG-PET/CT images reduced interobserver variation when determining the GTV in patients with CEC. FDG-PET/CT may increase the consistency of the radiographically determined GTV in patients with CEC.

Impact of 99mTc-GSA SPECT Image-Guided Inverse Planning on Dose-Function Histogram Parameters for Stereotactic Body Radiation Therapy Planning for Patients With Hepatocellular Carcinoma: A Dosimetric Comparison Study

Purpose:

To evaluate the impact of ^99mTc-labeled diethylene triamine pentaacetate-galactosyl human serum albumin (^99mTc-GSA) single-photon emission computed tomography (SPECT) image-guided inverse planning on the dose–function histogram (DFH) parameters for stereotactic body radiation therapy planning in patients with hepatocellular carcinoma (HCC).

Methods:

Eleven patients were enrolled in this study. The functional liver structure (FLS) was derived from SPECT thresholds of 60% to 80% of the maximum pixel value. Two treatment plans optimized without FLS (plan C) and with FLS (plan F) were designed for 50 Gy to the planning target volume (PTV). The DFH parameters were calculated as follows: Fx = (sum of the counts within the liver volume receiving a dose >x Gy/sum of the counts within the whole liver volume) × 100. Other parameters for the PTV included D₉₅, mean dose, conformity index (CI), and homogeneity index (HI).

Results:

Compared with plan C, plan F significantly reduced DFH parameters of F₅ to F₄₀ (P < .05). There were no significant differences in the parameters of the PTV of D₉₅, mean dose, CI, and HI and organs at risks (stomach, duodenum, spinal cord, and kidneys) between plans C and F.

Conclusion:

DFH analyses revealed that ^99mTc-GSA SPECT image-guided inverse planning provided dosimetric benefits related to sparing of liver function and may reduce hepatic toxicities.

Does care at a cardiac arrest centre improve outcome after out-of-hospital cardiac arrest? - A systematic review

AIM

To perform a systematic review to answer 'In adults with attempted resuscitation after non-traumatic cardiac arrest does care at a specialised cardiac arrest centre (CAC) compared to care in a healthcare facility not designated as a specialised cardiac arrest centre improve patient outcomes?'

METHODS

The PRISMA guidelines were followed. We searched bibliographic databases (Embase, MEDLINE and the Cochrane Library (CENTRAL)) from inception to 1st August 2018. Randomised controlled trials (RCTs) and non-randomised studies were eligible for inclusion. Two reviewers independently scrutinized studies for relevance, extracted data and assessed quality of studies. Risk of bias of studies and quality of evidence were assessed using ROBINS-I tool and GRADEpro respectively. Primary outcomes were survival to 30 days with favourable neurological outcomes and survival to hospital discharge with favourable neurological outcomes. Secondary outcomes were survival to 30 days, survival to hospital discharge and return of spontaneous circulation (ROSC) post-hospital arrival for patients with ongoing resuscitation. This systematic review was registered in PROSPERO (CRD 42018093369) RESULTS: We included data from 17 observational studies on out-of-hospital cardiac arrest (OHCA) patients in meta-analyses. Overall, the certainty of evidence was very low. Pooling data from only adjusted analyses, care at CAC was not associated with increased likelihood of survival to 30 days with favourable neurological outcome (OR 2.92, 95% CI 0.68-12.48) and survival to 30 days (OR 2.14, 95% CI 0.73-6.29) compared to care at other hospitals. Whereas patients cared for at CACs had improved survival to hospital discharge with favourable neurological outcomes (OR 2.22, 95% CI 1.74-2.84) and survival to hospital discharge (OR 1.85, 95% CI 1.46-2.34).

CONCLUSIONS

Very low certainty of evidence suggests that post-cardiac arrest care at CACs is associated with improved outcomes at hospital discharge. There remains a need for high quality data to fully elucidate the impact of CACs.

Spleen Dose-Volume Parameters as a Predictor of Treatment-related Lymphopenia During Definitive Chemoradiotherapy for Esophageal Cancer

AIM

Our study sought to identify dosimetric predictors of treatment-related lymphopenia during chemoradiotherapy for esophageal cancer.

MATERIALS AND METHODS

Patients with esophageal cancer who had received definitive chemoradiotherapy at our Institution were retrospectively assessed. The absolute volume of the spleen, body, and bone marrow that had received 5, 10, 20, and 30 Gy and the mean splenic dose were recorded.

RESULTS

Multivariate linear regression analysis revealed that docetaxel use and spleen dose-volume parameters (V5, V10, V20, V30, and mean splenic dose) were significant independent factors negatively influencing the absolute lymphocyte count at nadir. An increase of 1 Gy in mean splenic dose predicted a 2.9% decrease in nadir absolute lymphocyte count. Univariable logistic regression analysis showed that the mean splenic dose was a significant predictor of grade 4 lymphopenia. None of the body or bone marrow dose-volume parameters significantly predicted lymphopenia.

CONCLUSION

Higher spleen dose-volume parameters were associated with severe lymphopenia during chemoradiotherapy.

Short- and Long-Term Outcomes of Live Donor Renal Allografts From Older and Younger Donors

BACKGROUND

The rising demand for living renal donors has led to the recruitment of older donors. Findings vary, but these grafts appear to survive as long as grafts from standard criteria deceased and expanded criteria deceased donors. We investigated the effects of donor age ≥65 years and the presence or absence of donor antihypertensive therapy on patient condition 1 year after transplantation, and retrospectively examined 1-year (273 patients), 3-year (217 patients), and 5-year (140 patients) patient and graft survival.

METHODS

We divided 273 donor-recipient pairs into Group Y (donor age <65 years, n = 224) and Group O (donor age ≥65 years, n = 49). Group O was subdivided into donors receiving treatment for hypertension (subgroup O-1, n = 16) and those not receiving treatment for hypertension (subgroup O-2, n = 33). We compared results of 1 hour post-transplant biopsies and looked at a small number of 1 year post-transplant biopsies.

RESULTS

Although a significantly larger percentage of recipients from younger donors were undergoing preemptive transplantation, and the incidence of arteriosclerosis was significantly higher in the Group O kidneys, there were no significant differences between the 2 groups in terms of patient or graft survival at 1, 3, or 5 years; serum creatinine levels; or number of episodes of acute rejection. The presence or absence of donor antihypertensive treatment had no effect.

CONCLUSIONS

We found that donor age ≥65, with or without antihypertensive treatment, had no effect on graft or patient survival.

Effect of metal-containing topical agents on surface doses received during external irradiation

The ability of topical metal-containing agents (MCAs) to enhance radiation dermatitis remains controversial. In the present study, we evaluated increases in surface doses associated with topical agents at different application thicknesses and with MCAs versus non-metal containing agents (NMCAs). We assessed two clinically available MCAs, zinc oxide ointment (ZOO) and silver sulfadiazine cream (SSDC), and eight NMCAs. Surface doses were measured using a Markus chamber placed on a polystyrene phantom. To evaluate the role of application thickness, each agent was applied to the chamber in oil-slick (<0.1-mm), 1-mm and 5-mm layers prior to irradiation of a 10 × 10 cm field with 4-, 6- and 10-MV X-ray beams. The surface dose enhancement ratio (SDER) was calculated as the ratio of the surface dose with an agent to the dose without an agent. The SDER values for the eight NMCAs, ZOO and SSDC at an oil-slick thickness were 101.6-104.6% (mean: 103.3%), 104.5% and 105.0%, respectively, using a 6-MV X-ray beam. The corresponding values at a 1-mm thickness were 196.8-237.8% (mean: 215.7%), 229.3% and 201.4%, respectively, and those at a 5-mm thickness were 342.2-382.4% (mean: 357.9%), 357.1% and 352.6%, respectively. A similar tendency was found using 4- and 10-MV X-ray beams. The lack of a significant difference in surface dose enhancement between MCAs and NMCAs, particularly when applied in oil-slick layers, suggests that MCAs do not need to be avoided or applied in a restricted manner during radiotherapy for dosimetric reasons.

Improvement in pain interference after palliative radiotherapy for solid and hematologic painful tumors: a secondary analysis of a prospective observational study

Background

We previously demonstrated that patients with painful hematologic tumors were more likely to experience pain response after palliative radiotherapy (RT) than those with painful solid tumors. However, it is unknown whether change in pain interference differs between these two tumor types. In the present study, we carried out a secondary analysis of our previous prospective observational study to investigate this matter.

Methods

From patients undergoing palliative RT to treat painful tumors, Brief Pain Inventory data were collected at the start of RT and at the 1-, 2-, and 3- month follow-ups. The Mann-Whitney U test was used to compare changes in pain interference score from baseline between the two groups.

Results

Of the 237 patients, 203 (86%) had solid and 34 (14%) had hematologic index tumors planned to receive RT. At baseline, the groups did not differ significantly in terms of pain score, analgesic use, or pain interference score. At the 1-, 2-, and 3-month follow-ups, the changes in pain interference score from baseline did not differ significantly between the two groups. In both groups, all seven pain interference items, other than sleep in patients with hematologic tumors at the 2-month follow-up, were significantly improved (P < 0.05).

Conclusions

The two groups showed comparable benefit from RT in terms of improvement in pain interference. Patients with tumor-related pain should be offered the option of palliative RT, irrespective of whether the painful tumor is solid or hematologic.

Predictors of the Predominance of NonIndex Pain After Palliative Radiation Therapy for Painful Tumors

Purpose

Even when index pain (pain caused by the irradiated tumor) is palliated after radiation therapy (RT), patients may not derive the full benefits of RT in the presence of another, more intense pain. In this case-control study with prospectively collected data, we sought to identify predictors of the predominance of nonindex pain after palliative RT.

Methods and Materials

Brief Pain Inventory data were collected from patients who received RT for painful tumors. The treating radiation oncologists prospectively evaluated the intensity and origin of nonindex pain. Patients were diagnosed with predominance of other pain (POP) if nonindex pain of malignant or unknown origin was present and had a greater worst pain score than the index pain at the 1- or 2-month follow-up. Changes in pain interference from baseline to follow-up were compared between the 2 groups using Mann-Whitney U tests. Using variables that were identified as significant in a multivariable logistic regression analysis, we developed a prediction model for POP.

Results

Of the 170 patients who were evaluable at the 2-month follow-up, 24 (14%) were diagnosed with POP. At the 2-month follow-up examination of the patients with POP, none of the items of the pain interference scores were reduced from baseline; in contrast, patients without POP experienced significant reductions in all items. Multivariable analysis using the backward elimination method indicated that age ≤65 years, the presence of nonindex pain of malignant or unknown origin at baseline, and no opioid analgesic use at baseline were significant independent predictors of POP. As the number of the risk factors increased, the proportion of patients with POP increased.

Conclusions

We identified three predictors of POP. For patients likely to have POP, careful follow-up is important, and new palliative RT or analgesics should be used when needed.

A neuropathic pain component as a predictor of improvement in pain interference after radiotherapy for painful tumors: A secondary analysis of a prospective observational study

•

A neuropathic component was related to worse pain interference scores at baseline.

•

A neuropathic component predicted a greater reduction in pain interference.

•

Older patients and male patients tended to have a neuropathic component.

Background and purpose

We previously demonstrated that patients with a tumor-related neuropathic pain component were more likely to experience a pain response after radiotherapy (RT) than those without. It is unknown whether the presence of a neuropathic component also favorably influences pain interference. In a secondary analysis of our previous prospective observational study, we investigated if the presence of a neuropathic component of the index pain caused by the irradiated tumors predicts greater reduction in pain interference.

Material and methods

For patients scheduled for RT for painful tumors, Brief Pain Inventory data were collected at initiation of RT and 1, 2, and 3 months thereafter. Multivariable linear regression analyses were performed to investigate the effects of the presence of a neuropathic component on the changes in pain interference scores (i.e., follow-up minus baseline). We used 10 covariates as potential confounders.

Results

Of the 302 analyzable patients, 93 (31%) were diagnosed as having a neuropathic component of the index pain. Multivariable linear regression analyses revealed that all the point estimates of regression coefficients at 1-, 2-, and 3-month follow-up were negative values; some were statistically significant. At 2-month follow-up, patients with a neuropathic component experienced greater reductions in their pain interference scores for walking ability (p = 0.048), normal work (p = 0.021), sleep (p = 0.001), and enjoyment of life (p = 0.010) than those without it.

Conclusions

The presence of a neuropathic pain component predicted a greater reduction in pain interference after RT. Patients with neuropathic tumor-related pain should be offered the option of receiving palliative RT.

CCAT1 and CCAT2 long noncoding RNAs, located within the 8q.24.21 'gene desert', serve as important prognostic biomarkers in colorectal cancer

Background

8q24.21 is a frequently amplified genomic region in colorectal cancer (CRC). This region is often referred to as a 'gene desert' due to lack of any important protein-coding genes, highlighting the potential role of noncoding RNAs, including long noncoding RNAs (lncRNAs) located around the proto-oncogene MYC. In this study, we have firstly evaluated the clinical significance of altered expression of lncRNAs mapped to this genomic locus in CRC.

Patients and methods

A total of 300 tissues, including 280 CRC and 20 adjacent normal mucosa specimens were evaluated for the expression of 12 lncRNAs using qRT-PCR assays. We analyzed the associations between lncRNA expression and various clinicopathological features, as well as with recurrence free survival (RFS) and overall survival (OS) in two independent cohorts.

Results

The expression of CCAT1, CCAT1-L, CCAT2, PVT1, and CASC19 were elevated in cancer tissues (P = 0.039, <0.001, 0.018, <0.001, 0.002, respectively). Among these, high expression of CCAT1 and CCAT2 was significantly associated with poor RFS (P = 0.049 and 0.022, respectively) and OS (P = 0.028 and 0.015, respectively). These results were validated in an independent patient cohort, in which combined expression of CCAT1 and CCAT2 expression was significantly associated with a poor RFS (HR:2.60, 95% confidence interval [CI]: 1.04-6.06, P = 0.042) and a poor OS (HR:8.38, 95%CI: 2.68-37.0, P < 0.001). We established a RFS prediction model which revealed that combined expression of CCAT1, CCAT2, and carcinoembryonic antigen was a significant determinant for efficiently predicting RFS in stage II (P = 0.034) and stage III (P = 0.001) CRC patients.

Conclusions

Several lncRNAs located in 8q24.21 locus are highly over-expressed in CRC. High expression of CCAT1 and CCAT2 significantly associates with poor RFS and OS. The expression of these two lncRNAs independently, or in combination, serves as important prognostic biomarkers in CRC.

Predictors of Pain Palliation After Radiation Therapy for Painful Tumors: A Prospective Observational Study

PURPOSE

Although radiation therapy (RT) is an important part of treatment for cancer pain, prediction of the patient's pain response remains difficult. We evaluated the characteristics of patients, their tumors, and their pain to identify the predictors of pain palliation after RT for painful tumors.

METHODS

Our 3-center prospective observational study included patients scheduled for palliative or curative RT for painful tumors. Brief Pain Inventory data were collected at the start of RT and 1, 2, and 3 months thereafter. The pain response was assessed using the International Consensus Endpoint. The Mann-Whitney U-test was used to compare responders and nonresponders based on changes in the BPI scores. Predictors of the pain response were evaluated using the Fine-Gray model, in which death without a pain response was recorded as a competing risk. The independent variables were 11 a priori selected potential predictors with clinical relevance.

RESULTS

Of 302 analyzable patients, 262 (87%) had solid and 40 (13%) had hematologic tumors. The median total radiation dose was 30 Gy (range, 6-70.4 Gy). The pain response rate was 52% for 264 (87%) evaluable patients at 1-, 57% for 228 (75%) such patients at 2-, and 58% for 182 (60%) evaluable patients at 3-month follow-up. At 2-month follow-up, responders experienced a greater decrease in all 7 pain interference subscales of the Brief Pain Inventory compared to nonresponders. Multivariable analysis demonstrated that hematologic tumors (hazard ratio [HR], 1.85; 95% confidence interval [CI], 1.15-2.98), a neuropathic component of the index pain (HR, 1.50; 95% CI, 1.05-2.14), and opioid analgesic use before RT (HR, 0.65; 95% CI, 0.47-0.91) were independent significant predictors of pain response.

CONCLUSIONS

Patients with hematologic tumors, a neuropathic component of the index pain, and no treatment with opioid analgesics before RT were more likely to experience pain palliation after RT.

Dose-function Histogram Evaluation Using 99mTc-GSA SPECT/CT Images for Stereotactic Body Radiation Therapy Planning for Hepatocellular Carcinoma Patients: A Dosimetric Parameter Comparison

BACKGROUND/AIM

We evaluated the influence of previous treatments on the parametric discrepancies between dose-volume histograms (DVHs) and dose-function histograms (DFHs) generated based on ^99mTc-GSA SPECT images of hepatocellular carcinoma (HCC) patients treated with stereotactic body radiation therapy (SBRT).

PATIENTS AND METHODS

Twelve patients underwent SBRT at 30-40 Gy. Registration between planning CT and SPECT/CT images was performed, and DFH parameters were calculated as follows: Fx=(sum of the counts within the liver volume receiving a dose of more than x Gy/sum of the counts within the whole liver volume) ×100. The discrepancy between Fx and Vx (Dx) was also calculated.

RESULTS

The number of previous treatments for lesions other than SBRT-treated lesions (≥2 vs. <2) exhibited a significant influence on the absolute values of D₁₀, D₁₅, and D₂₀ (p<0.05).

CONCLUSION

Previous treatment significantly influences the parametric discrepancy between DFH and DVH.

Effective Treatment With Daclatasvir and Asunaprevir in Kidney Transplant Patients Infected With Hepatitis C Virus: A Report of Two Cases

BACKGROUND

Hepatitis C virus (HCV) infection is known to affect long-term patient and graft survivals after kidney transplantation (KT). Recently, combination therapy with the use of 2 oral direct-acting antivirals, daclatasvir (DCV) and asunaprevir (ASV) reportedly showed a high rate of HCV eradication. We report the safety and efficacy of DCV and ASV therapy in 2 KT patients.

METHODS

The safety and viral responses were investigated in a prospective study of KT patients infected with HCV genotype 1. Two patients received 60 mg DCV once daily plus 100 mg ASV twice daily for 24 weeks.

RESULTS

A 69-year-old woman and a 57-year-old man underwent DCV and ASV therapy for 24 weeks. In both cases, the HCV genotype was 1b. Case 1 had undergone KT twice and had received treatment with pegylated interferon and ribavirin. She received DCV and ASV therapy 12 years after the 2nd KT, and had undetectable virus after only 6 weeks of treatment and at 24 weeks after the end of treatment (SVR24). The post-transplantation immunosuppressive therapy at that time comprised tacrolimus, mycophenolate mofetil, and prednisolone. The other case, after failure of interferon treatment, received DCV and ASV therapy 27 years after his KT and achieved SVR24. His immunosuppressive regimen at that time was mizoribine and prednisolone. DCV and ASV therapy did not affect renal graft function or tacrolimus blood concentrations.

CONCLUSIONS

DCV and ASV therapy had high antiviral effect and a low rate of adverse events in KT patients.

Predictors of acute hematologic toxicity attributable to palliative radiotherapy: Analysis of patient characteristics and bone marrow dose-volume parameters

PURPOSE

As predictors of hematologic toxicity (HT) after palliative radiotherapy (RT) have been studied insufficiently, we explored predictors of leukopenia, neutropenia, and thrombocytopenia attributable to palliative RT.

METHODS

We retrospectively assessed patients with various solid tumors who had received palliative RT at our institution. Excluded from our study were patients who had undergone chemotherapy from one month before to one month after the start of RT. To measure the bone marrow dose, all bones were delineated, and the absolute volume of bone marrow that had received 5, 10, 20, and 30 Gy was recorded. Univariate and multivariate logistic regression analysis was performed to identify variables associated with leukopenia, neutropenia, or thrombocytopenia of grade 2 or higher (HT2+).

RESULTS

Of 68 patients, 17 (25%) developed HT2+. Grade ≥ 2 leukopenia developed in 13 patients (19%), neutropenia in 8 (12%), and thrombocytopenia in 6 (9%). Only one patient experienced ≥ grade 3 toxicity. The median baseline and nadir white blood cell count (WBC) was 6.950 and 4.650x109/l, respectively; the absolute neutrophil count (ANC) was 5.236 and 3.307x109/l, respectively, and the platelet count was 249 and 177.5x109/l, respectively. Multivariate analysis revealed that female gender and a lower baseline WBC and ANC were significant independent predictors of HT2+. No bone marrow dose-volume parameter was a significant predictor of HT2+.

CONCLUSIONS

Overall, HT was relatively mild. Female gender and lower baseline WBC and ANC may be predictors of HT elicited by palliative RT.

Four-dimensional cone-beam computed tomography-guided radiotherapy for gastric lymphoma

PURPOSE

We describe a treatment method with four-dimensional cone-beam computed tomography (4D-CBCT)-guided radiotherapy for gastric lymphoma.

MATERIALS AND METHODS

We performed image-guided radiotherapy (IGRT) with 15 fractions for a gastric mucosa-associated lymphoid tissue lymphoma patient, using 4D-CBCT. The stomach was delineated based on 4D-CT images. For image guidance, an automatic registration between planning CT and 4D-CBCT images was performed based on the bony anatomy (bone matching), followed by manual registration based on the stomach in 4D-CBCT images of all 10 phases (4D matching). We calculated the covering ratio (CR) with variable stomach-to-planning target volume (PTV) margins, based on the images of all phases [CR (%) = the number of covering phases/all 150 phases × 100].

RESULTS

The patient underwent radiotherapy (RT) as scheduled, without any significant adverse effects. The appropriate PTV margins (CR ≥ 95%) were 25 mm (CR 99.3%) and 15 mm (CR 98.7%) for bone and 4D matching, respectively.

CONCLUSION

4D matching using 4D-CBCT is appropriate for IGRT of gastric lymphomas.

Radiotherapy for T3N0 glottic carcinoma without cord fixation: elective nodal irradiation or not?

Background

Although the T3 category has been changed in the sixth edition of the TNM staging system proposed by the Union for International Cancer Control (UICC), the appropriate clinical target volume (CTV) of elective nodal irradiation (ENI) for T3N0 glottic carcinoma without cord fixation, which was formerly treated as a T1-2N0 disease, is not fully discussed.

Materials and Methods

We retrospectively analyzed 64 patients staged or restaged as T3N0 disease without cord fixation. All patients received irradiation to the primary lesion alone using opposed lateral fields. Surgery was performed in 10 patients without tumor regression after the delivery of 40 Gy. The other 54 patients received a median total dose of 66 Gy. Concurrent chemoradiotherapy (CRT) with low-dose cisplatin and UFT (low-dose CRT) and docetaxel, cisplatin, and 5-fluorouracil (TPF-CRT) were performed in 23 and 19 patients, respectively.

Results

Eighteen (28.1%) patients suffered treatment failure; all were recorded as local failure alone. The 5-year local control rates for RT alone, low-dose CRT, and TPF-CRT groups were 51.7%, 61.6%, and 93.8%, respectively (p = 0.027). The 5-year laryngeal preservation rates for RT alone, low-dose CRT, and TPF-CRT groups were 57.4%, 81.6%, and 89.5%, respectively (p = 0.048).

Conclusions

The rate of regional failure was zero when irradiating the primary lesion alone using opposed lateral fields. This treatment technique covers the most level III regions; hence, CTV for ENI should include level III alone.