Analysis of Plasma Circulating Tumor DNA in Borderline Resectable Pancreatic Cancer Treated with Neoadjuvant Modified FOLFIRINOX: Clinical Relevance of DNA Damage Repair Gene Alteration Detection

PURPOSE

There are no reliable biomarkers to guide treatment for patients with borderline resectable pancreatic cancer (BRPC) in the neoadjuvant setting. We used plasma circulating tumor DNA (ctDNA) sequencing to search biomarkers for patients with BRPC receiving neoadjuvant mFOLFIRINOX in our phase 2 clinical trial (NCT02749136).

MATERIALS AND METHODS

Among the 44 patients enrolled in the trial, patients with plasma ctDNA sequencing at baseline or post-operation were included in this analysis. Plasma cell-free DNA isolation and sequencing were performed using the Guardant 360 assay. Detection of genomic alterations, including DNA damage repair (DDR) genes, were examined for correlations with survival.

RESULTS

Among the 44 patients, 28 patients had ctDNA sequencing data qualified for the analysis and were included in this study. Among the 25 patients with baseline plasma ctDNA data, 10 patients (40%) had alterations of DDR genes detected at baseline, inclu-ding ATM, BRCA1, BRCA2 and MLH1, and showed significantly better progression-free survival than those without such DDR gene alterations detected (median, 26.6 vs. 13.5 months; log-rank p=0.004). Patients with somatic KRAS mutations detected at baseline (n=6) had significantly worse overall survival (median, 8.5 months vs. not applicable; log-rank p=0.003) than those without. Among 13 patients with post-operative plasma ctDNA data, eight patients (61.5%) had detectable somatic alterations.

CONCLUSION

Detection of DDR gene mutations from plasma ctDNA at baseline was associated with better survival outcomes of pati-ents with borderline resectable pancreatic ductal adenocarcinoma treated with neoadjuvant mFOLFIRINOX and may be a prognostic biomarker.

Analysis of plasma circulating tumor DNA in borderline resectable pancreatic ductal adenocarcinoma treated with neoadjuvant modified FOLFIRINOX: Clinical relevance of DNA damage repair gene alterations

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Background: There is no reliable biomarker to guide treatment for patient with borderline resectable pancreatic ductal adenocarcinoma (PDAC) treated with neoadjuvant modified (m)FOLFIRINOX. We investigated the role of plasma circulating tumor DNA (ctDNA) sequencing to discover potential biomarkers for patients treated with neoadjuvant mFOLFIRINOX in our phase 2 clinical trial (ClinicalTrials.gov identifier: NCT02749136). Methods: Among 44 patients enrolled in the trial, patients with plasma ctDNA analysis performed at baseline or post-operative period were included in the analysis. Plasma cell-free DNA isolation and sequencing of ctDNA were performed using the Guardant 360 assay. Association of clinical outcomes with germline or somatic mutations of DNA damage repair (DDR) genes was analyzed. Somatic alterations other than DDR genes were also analyzed to find potential biomarkers of neoadjuvant mFOLFIRINOX. Progression free-survival (PFS) was defined as time from the initiation of mFOLFIRINOX to disease progression or any cause of death. Overall survival (OS) was defined as the time from the initiation of mFOLFIRINOX to any cause of death. Results: Among 44 patients, 28 patients had ctDNA sequencing data qualified for the analysis and were included in this study (15 patients with baseline data only, 3 patients with post-operative data only, and 10 patients with both baseline and post-operative data). Median age was 59 (range, 41-73) years and 15 patients (53.6%) were male. Among 25 patients with baseline plasma ctDNA data, 11 patients (44%) had somatic or germline alteration of DDR genes detected at baseline including ATM, BRCA1, BRCA2 and MLH1, and showed significantly better PFS than those without such DDR gene alterations (median 26.6 vs. 13.5 months, log-rank p = 0.004). Although there was a trend for better OS in patients with DDR gene alterations, this was not statistically significant (log-rank p = 0.29). The most observed baseline somatic alteration was TP53 (n = 7, 28%), followed by KRAS (n = 6, 24%). Patients with somatic KRAS mutation at baseline had significantly worse OS (median 8.5 months vs. not applicable, log-rank p = 0.003) than those without. Among 13 patients with post-operative plasma ctDNA data, 8 patients (61.5%) had detectable somatic alterations. Conclusions: Detection of germline or somatic mutations of DDR genes from plasma ctDNA at baseline was associated with better survival outcomes of patients with borderline resectable PDAC treated with neoadjuvant mFOLFIRINOX. Detection of DDR gene alterations from plasma ctDNA may have a potential role as biomarker for prognosis in patients with borderline resectable PDAC treated with mFOLFIRINOX.

Prognostic implication of serum AFP in patients with hepatocellular carcinoma treated with regorafenib

Background: This multicenter study investigated the predictive value of baseline AFP and on-treatment AFP response for survival in hepatocellular carcinoma (HCC) patients with regorafenib. Materials & methods: A total of 578 patients with HCC treated with regorafenib from 12 institutions in South Korea and Italy were included. Baseline AFP (cutoff, 400 ng/ml) and AFP response (20% reduction from baseline) were analyzed for overall survival (OS) and progression-free survival (PFS). Results: Baseline AFP below 400 ng/ml was a significant factor that was independently associated with longer OS and PFS. AFP response was also a significant factor independently associated with longer OS and PFS. Conclusion: Baseline AFP and AFP response may be used as prognostic factors for survival in HCC treated with regorafenib.

Serum vitamin D level mitigates fractional exhaled nitric oxide linked to bisphenol-A in school-aged children

OBJECTIVE

Previous studies on the relationship of bisphenol-A (BPA) with fractional exhaled nitric oxide (FeNO) had conflicting results, suggesting that other factors may modulate this relationship. Thus, we investigated the modulating effect of vitamin D on the relationship of BPA with FeNO in children.

PATIENTS AND METHODS

This study recruited 432 children (10 to 12 years old) from the general pediatric population of Korea between June and July 2017. We conducted measurements of urinary BPA, serum vitamin D, specific serum IgE, FeNO, and data from impulse oscillometry (reactance area [AX], airway resistance at 5 Hz [Rrs5] and 20 Hz [Rrs10], and the difference of Rrs5 and Rrs20 [Rrs5-20]).

RESULTS

Serum vitamin D (adjusted β =- 0.014, p=0.002) and urinary BPA (β = 0.006, p<0.001) level was significantly associated with FeNO. Urinary BPA level was significantly associated with FeNO in children with low vitamin D levels (≤23 ng/mL; αβ = 0.006, p < 0.001), but not in children with high vitamin D levels (>23 ng/mL). The interaction of vitamin D and BPA had a significant effect on FeNO (pint = 0.005). There was no relationship with the airway lung function (Rrs5, AX, and Rrs5-20) to serum vitamin D and urinary BPA level. Vitamin D ameliorated the BPA-mediated increase of FeNO in children.

CONCLUSIONS

These results suggest that children with low vitamin D levels may be more susceptible to airway inflammation due to BPA.

A randomized phase III trial comparing adjuvant single-agent S1, S-1 with oxaliplatin, and postoperative chemoradiation with S-1 and oxaliplatin in patients with node-positive gastric cancer after D2 resection: the ARTIST 2 trial☆

BACKGROUND

Adjuvant chemotherapy and chemoradiotherapy are some of the standards of care for gastric cancer (GC). The Adjuvant chemoRadioTherapy In Stomach Tumors (ARTIST) 2 trial compares two adjuvant chemotherapy regimens and chemoradiotherapy in patients with D2-resected, stage II or III, node-positive GC.

PATIENTS AND METHODS

The ARTIST 2 compared, in a 1:1:1 ratio, three adjuvant regimens: oral S-1 (40-60 mg twice daily 4 weeks on/2 weeks off) for 1 year, S-1 (2 weeks on/1 week off) plus oxaliplatin 130 mg/m² every 3 weeks (SOX) for 6 months, and SOX plus chemoradiotherapy 45 Gy (SOXRT). Randomization was stratified according to surgery type (total or subtotal gastrectomy), pathologic stage (II or III), and Lauren histologic classification (diffuse or intestinal/mixed). The primary endpoint was disease-free survival (DFS) at 3 years; a reduction of 33% in the hazard ratio (HR) for DFS with SOX or SOXRT, when compared with S-1, was considered clinically meaningful. The trial is registered at clinicaltrials.gov (NCT0176146).

RESULTS

A total of 546 patients were recruited between February 2013 and January 2018 with 182, 181, and 183 patients in the S-1, SOX, and SOXRT arms, respectively. Median follow-up period was 47 months, with 178 DFS events observed. Estimated 3-year DFS rates were 64.8%, 74.3%, and 72.8% in the S-1, SOX, and SOXRT arms, respectively. HR for DFS in the control arm (S-1) was shorter than that in the SOX and SOXRT arms: S-1 versus SOX, 0.692 (P = 0.042) and S-1 versus SOXRT, 0.724 (P = 0.074). No difference in DFS was found between SOX and SOXRT (HR 0.971; P = 0.879). Adverse events were as anticipated in each arm, and were generally well-tolerated and manageable.

CONCLUSIONS

In patients with curatively D2-resected, stage II/III, node-positive GC, adjuvant SOX or SOXRT was effective in prolonging DFS, when compared with S-1 monotherapy. The addition of radiotherapy to SOX did not significantly reduce the rate of recurrence after D2 gastrectomy.

Effects of Coconut Materials on In vitro Ruminal Methanogenesis and Fermentation Characteristics

The objective of this study was to evaluate the in vitro effects of coconut materials on ruminal methanogenesis and fermentation characteristics, in particular their effectiveness for mitigating ruminal methanogenesis. Fistulated Holstein cows were used as the donor of rumen fluid. Coconut materials were added to an in vitro fermentation incubated with rumen fluid-buffer mixture and timothy substrate for 24 h incubation. Total gas production, gas profiles, total volatile fatty acids (tVFAs) and the ruminal methanogens diversity were measured. Although gas profiles in added coconut oil and coconut powder were not significantly different, in vitro ruminal methane production was decreased with the level of reduction between 15% and 19% as compared to control, respectively. Coconut oil and coconut powder also inhibited gas production. The tVFAs concentration was increased by coconut materials, but was not affected significantly as compared to control. Acetate concentration was significantly lower (p<0.05), while propionate was significantly higher (p<0.05) by addition of the coconut materials than that of the control. The acetate:propionate ratio was significantly lowered with addition of coconut oil and coconut powder (p<0.05). The methanogens and ciliate-associated methanogens in all added coconut materials were shown to decrease as compared with control. This study showed that ciliate-associated methanogens diversity was reduced by more than 50% in both coconut oil and coconut powder treatments. In conclusion, these results indicate that coconut powder is a potential agent for decreasing in vitro ruminal methane production and as effective as coconut oil.

Predictive factors for gastroduodenal toxicity based on endoscopy following radiotherapy in patients with hepatocellular carcinoma

PURPOSE

The aim of this work was to determine predictive factors for gastroduodenal (GD) toxicity in hepatocellular carcinoma (HCC) patients who were treated with radiotherapy (RT).

PATIENTS AND METHODS

A total of 90 HCC patients who underwent esophagogastroduodenoscopy (EGD) before and after RT were enrolled. RT was delivered as 30-50 Gy (median 37.5 Gy) in 2-5 Gy (median 3.5 Gy) per fraction. All endoscopic findings were reviewed and GD toxicities related to RT were graded by the Common Toxicity Criteria for Adverse Events, version 3.0. The predictive factors for the ≥ grade 2 GD toxicity were investigated.

RESULTS

Endoscopic findings showed erosive gastritis in 14 patients (16 %), gastric ulcers in 8 patients (9 %), erosive duodenitis in 15 patients (17 %), and duodenal ulcers in 14 patients (16 %). Grade 2 toxicity developed in 19 patients (21 %) and grade 3 toxicity developed in 8 patients (9 %). V25 for stomach and V35 for duodenum (volume receiving a RT dose of more than x Gy) were the most predictive factors for ≥ grade 2 toxicity. The gastric toxicity rate at 6 months was 2.9 % for V25 ≤ 6.3 % and 57.1 % for V25 > 6.3 %. The duodenal toxicity rate at 6 months was 9.4 % for V35 ≤ 5.4 % and 45.9 % for V35 > 5.4 %. By multivariate analysis including the clinical factors, V25 for stomach and V35 for duodenum were the significant factors.

CONCLUSION

EGD revealed that GD toxicity is common following RT for HCC. V25 for the stomach and V35 for the duodenum were the significant factors to predict ≥ grade 2 GD toxicity.

Evaluation of anatomical landmark position differences between respiration-gated MRI and four-dimensional CT for radiation therapy in patients with hepatocellular carcinoma

OBJECTIVE

To measure the accuracy of position differences in anatomical landmarks in gated MRI and four-dimensional CT (4D-CT) fusion planning for radiation therapy in patients with hepatocellular carcinoma (HCC).

METHODS

From April to December 2009, gated MR and planning 4D-CT images were obtained from 53 inoperable HCC patients accrued to this study. Gated MRI and planning 4D-CT were conducted on the same day. Manual image fusions were performed by matching the vertebral bodies. Liver volumes and three specific anatomical landmarks (portal vein conjunction, superior mesenteric artery bifurcation, and other noticeable points) were contoured from each modality. The points chosen nearest the centre of the four landmark points were compared to measure the accuracy of fusion.

RESULTS

The average distance differences (±standard deviation) of four validation points were 5.1 mm (±4.6 mm), 5.6 mm (±6.2 mm), 5.4 mm (±4.5 mm) and 5.1 mm (±4.8 mm). Patients who had ascites or pulmonary disease showed larger discrepancies. MRI-CT fusion discrepancy was significantly correlated with positive radiation response (p<0.05).

CONCLUSIONS

Approximately 5-mm anatomical landmark positional differences in all directions were found between gated MRI and 4D-CT fusion planning for HCC patients; the gap was larger in patients with ascites or pulmonary disease.

ADVANCES IN KNOWLEDGE

There were discrepancies of approximately 5 mm in gated MRI-CT fusion planning for HCC patients.

Anti-IL-33 antibody has a therapeutic effect in a murine model of allergic rhinitis

BACKGROUND

Interleukin (IL)-33 is involved in the Th2 immune response and could play an essential role in nasal allergy. Therefore, we aimed to investigate the therapeutic potential of anti-IL-33 for allergic rhinitis (AR).

METHODS

Twenty-four BALB/c mice were used. In group A (control group, n = 6), mice were sensitized and challenged with saline. Group B [ovalbumin (OVA) group, n = 6] mice received intraperitoneal and intranasal OVA challenge. In group C (control IgG group, n = 6), mice were injected intraperitoneally with rabbit control IgG before OVA challenge. In group D (anti-IL-33 group, n = 6), anti-IL-33 was injected before challenge. We evaluated the number of nose-scratching events and external morphology; serum total and OVA-specific IgE; number of eosinophils, neutrophils, and lymphocytes in bronchoalveolar lavage (BAL) fluid; histopathologic examination of nasal cavity; and IL-4, IL-5, and IL-13 in BAL fluid.

RESULTS

Anti-IL-33 treatment significantly reduced the nose-scratching events and ameliorated skin denudation. Serum total and OVA-specific IgE was significantly decreased in group D. The number of eosinophils in BAL fluid was also significantly decreased. Eosinophilic infiltration in the nasal cavity was significantly decreased in group D. IL-4, IL-5, and IL-13 in BAL fluid were also significantly decreased after treatment.

CONCLUSIONS

Anti-IL-33 antibody has a therapeutic potential for experimental AR.

Diagnostic dilemma of pseudoprogression in the treatment of newly diagnosed glioblastomas: the role of assessing relative cerebral blood flow volume and oxygen-6-methylguanine-DNA methyltransferase promoter methylation status

BACKGROUND AND PURPOSE

Methylation of the MGMT gene promoter is associated with a favorable prognosis in adult patients with GBM treated with TMZ. We determined the incidence of pseudoprogression according to the MGMT methylation status and the potential value of DSC perfusion MR images for predicting pseudoprogression.

MATERIALS AND METHODS

New or enlarged enhancing lesions after CCRT in adult patients with newly diagnosed GBMs were prospectively assessed by measuring their rCBV by using DSC perfusion MR images. Tumor tissue was assayed to determine MGMT promoter methylation status. All patients were regularly followed up at an interval of 2 months by MR images, including DSC perfusion MR images.

RESULTS

Ninety eligible patients were enrolled in this study. After CCRT, new or enlarged enhanced lesions were found in 59 of 90 patients, which were subsequently classified as pseudoprogression (26 patients, 28.9%) and real progression (33 patients, 36.7%). Overall, there was a significant difference in the mean rCBV between pseudoprogression and real tumor progression (P = .003). The ROC curve revealed that an rCBV ratio >1.47 had an 81.5% sensitivity and a 77.8% specificity. The unmethylated MGMT promoter group had a significant difference of mean rCBV between pseudoprogression and real progression (P = .009), though the methylated MGMT promoter group had no significant difference (P = .258).

CONCLUSIONS

The current study suggests that rCBV measured by DSC perfusion MR images has a differential impact on the predictability of pseudoprogression in patients with GBM.

Epigenotype-phenotype correlations in Silver-Russell syndrome

Background

Silver–Russell syndrome (SRS) is characterised by intrauterine growth restriction, poor postnatal growth, relative macrocephaly, triangular face and asymmetry. Maternal uniparental disomy (mUPD) of chromosome 7 and hypomethylation of the imprinting control region (ICR) 1 on chromosome 11p15 are found in 5–10% and up to 60% of patients with SRS, respectively. As many features are non-specific, diagnosis of SRS remains difficult. Studies of patients in whom the molecular diagnosis is confirmed therefore provide valuable clinical information on the condition.

Methods

A detailed, prospective study of 64 patients with mUPD7 (n=20) or ICR1 hypomethylation (n=44) was undertaken.

Results and conclusions

The considerable overlap in clinical phenotype makes it difficult to distinguish these two molecular subgroups reliably. ICR1 hypomethylation was more likely to be scored as ‘classical’ SRS. Asymmetry, fifth finger clinodactyly and congenital anomalies were more commonly seen with ICR1 hypomethylation, whereas learning difficulties and referral for speech therapy were more likely with mUPD7. Myoclonus-dystonia has been reported previously in one mUPD7 patient. The authors report mild movement disorders in three further cases. No correlation was found between clinical severity and level of ICR1 hypomethylation. Use of assisted reproductive technology in association with ICR1 hypomethylation seems increased compared with the general population. ICR1 hypomethylation was also observed in affected siblings, although recurrence risk remains low in the majority of cases. Overall, a wide range of severity was observed, particularly with ICR1 hypomethylation. A low threshold for investigation of patients with features suggestive, but not typical, of SRS is therefore recommended.

Tandem high-dose chemotherapy and autologous stem cell rescue in patients over 1 year of age with stage 4 neuroblastoma

From June 1997 to August 2005, 52 consecutive newly diagnosed stage 4 neuroblastoma patients over 1 year of age were assigned to receive tandem high-dose chemotherapy and autologous stem cell rescue (HDCT/ASCR) as consolidation therapy. Fifty of the 52 patients underwent a first HDCT/ASCR and 44 patients underwent a second HDCT/ASCR. Eight patients (15.4%) died from treatment-related toxicity (seven during the second HDCT/ASCR). Total body irradiation (TBI) in the first HDCT/ASCR and a shorter interval (< 12 weeks) between the first and second HDCT/ASCR were associated with a higher rate of treatment-related death in the second HDCT/ASCR (P = 0.032 and 0.095, respectively). The tumor relapsed or progressed in 11 patients, and 33 patients remained event free with a median follow-up of 53 months (range 19-117) from diagnosis. The 5-year event-free survival (EFS) (+/- 95% confidence interval) for all 52 patients was 62.1+/-13.7%. The application of TBI and local radiotherapy, and a longer interval between the first and second HDCT/ASCR were independently associated with a better EFS (P = 0.026, 0.007 and 0.020, respectively). However, further studies will be needed to decrease the toxic death rate in the second HDCT/ASCR while reducing the relapse rate.

Patterns of failure in gastric carcinoma after D2 gastrectomy and chemoradiotherapy: a radiation oncologist's view

The risk of locoregional recurrence in resected gastric adenocarcinoma is high, but the benefit of adjuvant treatment remains controversial. In particular, after extended lymph node dissection, the role of radiotherapy is questionable. Since 1995, we started a clinical protocol of adjuvant chemoradiotherapy after D2 gastrectomy and analysed the patterns of failure for 291 patients. Adjuvant chemotherapy consisted of five cycles of fluorouracil and leucovorin, and concurrent radiotherapy was given with 4500 cGy from the second cycle of chemotherapy. With a median follow-up of 48 months, 114 patients (39%) showed any type of failure, and the local and regional failures were seen in 7% (20 out of 291) and 12% (35 out of 291), respectively. When the recurrent site was analysed with respect to the radiation field, in-field recurrence was 16% and represented 35% of all recurrences. Our results suggest that adjuvant chemoradiotherapy has a potential effect on reducing locoregional recurrence. Moreover, low locoregional recurrence rates could give a clue as to which subset of patients could be helped by radiotherapy after D2 gastrectomy. However, in order to draw a conclusion on the role of adjuvant radiotherapy, a randomised study is needed.

Postoperative chemoradiotherapy for gastric cancer

BACKGROUND

We report the results of postoperative chemoradiotherapy after curative resection in gastric cancer patients.

PATIENTS AND METHODS

Patients with gastric cancer staged IB to IV(M0) were treated with chemoradiotherapy after curative resection with extensive (D2) lymph node dissection. Nodal metastases were observed in 261 (90%) patients. The chemotherapy consisted of fluorouracil 400 mg/m(2) plus leucovorin 20 mg/m(2) for 5 days, followed by 4500 cGy of radiotherapy for 5 weeks with fluorouracil and leucovorin on the first 4 days and the last 3 days of radiotherapy. Two 5-day cycles of chemotherapy were given 4 weeks after the completion of radiotherapy.

RESULTS

Of 290 patients accrued, 229 (79%) patients completed chemoradiotherapy as planned. With a median follow-up of 49 months, 114 (34%) patients have relapsed: 33 (29%) locoregional relapses, 76 (67%) peritoneal relapses and 41 (36%) distant metastases. The 5-year overall and relapse-free survivals were 60% and 57%, respectively. Tolerance was acceptable, the main toxicity being neutropenia.

CONCLUSIONS

This postoperative chemoradiotherapy after curative resection of gastric cancer was feasible, with acceptable toxicities. Whether this adjuvant therapy in gastric cancer patients that have undergone a D2 lymph node dissection impacts on survival or reduces the incidence of relapses remains to be studied.

Successive double high-dose chemotherapy with peripheral blood stem cell rescue collected during a single leukapheresis round in patients with high-risk pediatric solid tumors: a pilot study in a single center

In total, 18 of 26 double high-dose chemotherapies (HDCT) in pediatric solid tumors were rescued with peripheral blood stem cells collected during a single leukapheresis round (single-harvest group, SHG). In the remaining eight HDCT, additional leukapheresis were necessary after the first HDCT (HDCT1) to rescue the second HDCT (HDCT2) (double-harvest group, DHG). Stem cell collection after HDCT1 was inefficient and delayed in patients who had received prior chemotherapy before HDCT1. The interval between HDCT1 and HDCT2 was shorter in SHG than in DHG (median 62.5 days vs 178.5 days, P-value=0.002). Hematologic recovery in HDCT2 was delayed compared to HDCT1. However, there was no difference in hematologic recovery between SHG and DHG. A high rate of treatment-related mortality (TRM) was recorded during HDCT2, but there was no evidence that the shorter interval caused a higher rate of TRM (P-value=0.454). The probability of disease-free survival at 2 years after HDCT2 in the SHG and DHG were 66.7 and 25.0%, respectively (P-value=0.031). Therefore, to administer the second HDCT earlier in double HDCT, and thus to improve the survival of patients with high-risk solid tumors, the single-harvest approach is recommended rather than the double-harvest approach.

Preoperative concurrent chemoradiotherapy for stage IIIA non-small cell lung cancer

Thirty-one patients with stage IIIA non-small cell lung cancer (NSCLC) were treated with preoperative concurrent chemoradiotherapy (CCRT) followed by surgery. The treatment protocol could not be completed in eight patients. The acute hematologic toxicities of grade III or IV occurred in 48.4%, (15/31) after the first chemotherapy cycle, and in 39.1% (9/23) after the second cycle. The most common non-hematologic toxicity was radiation esophagitis. Surgery was attempted in 23 patients and successful in 22 patients (resection rate = 71.0%. Pathologic complete response and down-staging were achieved in 13.6% (3/22) and 68.2% (15/22). The median survival period, 2-year overall survival, local control and disease-free survival rates of all 31 patients and of 22 patients who underwent surgery were 19 months, 37.2%, 49.1%, 35.5%, and 19 months, 43.2%, 51.8%, 25.6%, respectively. On the basis of our observations, preoperative CCRT followed by surgery for stage IIIA NSCLC has resulted in outcomes comparable with those in previous reports.

Fractionated stereotactic radiation therapy for extracranial head and neck tumors

BACKGROUND

This study is to report the clinical experiences of fractionated stereotactic radiation therapy (FSRT) for extracranial head and neck tumors.

METHODS AND MATERIALS

Between the period of July 1995 and November 1998, 48 patients with extracranial head and neck tumors were given FSRT as a boost and sole modality. Individualized treatment planning was performed using XKnife-3 system with relocatable Gill-Thomas-Cosman frame. In 24 patients, FSRT was applied as a boost technique following the 2-dimensional conventional external radiation therapy (ERT); in 24 patients FSRT was the sole radiotherapy modality. The primary diseases in the boost group consisted of nasopharynx cancer (19), lacrimal gland adenoid cystic carcinoma (3), orbital lymphoma (1), and skull-base recurrence of maxillary sinus adenoid cystic carcinoma (1). The primary diseases in the sole modality group consisted of recurrent nasopharynx cancer (12), orbital pseudotumor (4), skull-base recurrence of maxillary sinus, submandibular gland, and hypopharynx cancers (3), orbital rhabdomyosarcoma (2), orbital lymphoma (1), orbital metastasis of neuroblastoma (1), and nasal cavity melanoma (1). The fractionation schedule was to give 5 treatments per one week and the fractional doses were 2.0-3 Gy depending on the treatment aim and the FSRT volume. The FSRT doses varied depending on the nature of the primary diseases.

RESULTS

The local tumor response in nasopharynx cancer patients was excellent compared to retrospective data without occurrence of unexpectedly severe complication. FSRT to other regions was well tolerated by the patients and resulted in good to excellent local tumor responses with no unacceptable side effects as expected by the authors.

CONCLUSION

Based on the current observations, FSRT is a very effective and safe modality in the treatment of extracranial head and neck tumors.

Prompt radiation oncology record access by patient centered digital image chart system

The authors have developed and evaluated a radiation oncology digital image chart system (RODICS). With this system we could achieve paperless and filmless practice, and thus improved operational efficiency within the department. In this paper, we describe characteristics and clinical usage of RODICS.

A glass compensator filter to improve breast image quality in radiation therapy simulation

PURPOSE

To improve the image quality of simulation films in tangential radiotherapy for breast cancer, we have designed a new compensator filter for the variation of breast contour using high-density-glass material.

METHODS AND MATERIALS

The measurements and analyses of the body contour were done using CT scans, taken in the treatment position, of 20 breast cancer patients. The maximum tissue deficit that needed to be compensated for was 8 cm, and the authors fabricated the compensator system using high-density-glass material to maintain transparency. The glass compensator can be attached to the accessory mount of the simulator head and its position can be easily adjusted according to breast shape and position. The image qualities of simulation films taken with and without the glass compensator in tangential breast radiotherapy field were compared and the film densitometry was performed using the humanoid phantom.

RESULTS

Using this compensator system, the overall image quality improved, resulting in enhanced contrast and resolution of the breast simulation image. The delineator wires for the beam margins were also well depicted, and the surgical clips within the breast tissue can be easily demonstrated. The film densitometry resulted in much less saturation over the breast tissue when using the glass compensator.

CONCLUSION

Using the glass compensator system, the geographical miss may be reduced with the virtue of the improved image quality.

Analysis of correlation between rectal complications and rectal dose following high dose rate intracavitary radiotherapy in patients with uterine cervix cancer: in vivo dosimetric analysis

PURPOSE

To investigate the correlation between late rectal complications and rectal dose in uterine cervix cancer patients treated with high dose rate intracavitary radiotherapy (HDR ICR) and to analyze dose factors reducing complications.

METHODS

A retrospective analysis was done of 74 patients treated with external beam RT and HDR ICR between 1995 and 1997. Radiotherapy (RT) consisted of a median 50.4 Gy external beam plus six fractions of HDR ICR given two times per week, concurrent with the last three weeks of external beam therapy, to a total dose of median 24 Gy to point A or the reference point. Rectal doses were calculated at rectal reference points using barium contrast criteria. In vivo measurement of rectal dose was performed with thermoluminescent dosimeters (TLD) immediately prior to the first fraction of HDR ICR.

RESULTS

Eight patients developed rectal complications (11%). There was a significant difference between measured rectal doses for patients with rectal complications and those without (p < 0.05), and the doses were higher in complicated patients. A significant increase in the probability of development of complications was found for patients receiving measured rectal doses of ICR fractional dose 320 cGy or more, ICR total dose 2000 cGy or more, and ICR% to point A 80% or more.

CONCLUSIONS

This study showed that in vivo dosimetry using TLD during HDR ICR could have a useful role as a predictor of late rectal complications. Dose limitation to the rectum could possibly be achieved by thorough vaginal packing or use of an applicator with proper shielding while maintaining a high dose to the tumor.

Design and development of new collimator cones for fractionated stereotactic radiation therapy in Samsung Medical Center

PURPOSE

In stereotactic radiotherapy using X-Knife system, the commercially supplied collimator cone system had a few mechanical limitations. The authors have developed new collimator cones to overcome these limitations and named them "SMC type" collimator cones.

METHODS

We made use of cadmium-free cerrobend alloy within the stainless steel cylinder housing. We made nine cones of relatively larger sizes (3.0 cm to 7.0 cm in diameter) and of shorter length with bigger clearance from the isocenter than the commercial cones. The cone housing and the collimator cones were designed to insert into the wedge mount of the gantry head to enable double-exposure linac-gram taking.

RESULTS

The mechanical accuracy of pointing to the isocenter was tested by ball test and cone rotation test, and the dosimetric measurements were performed, all of which were with satisfactory results. A new innovative quality assurance procedure using linac-grams on the patients at the actual treatment setup was attempted after taking 10 sets of AP and lateral linac-grams and the overall mechanical isocenter accuracy was excellent (average error = 0.4 +/- 0.2 mm).

CONCLUSIONS

We have developed the SMC type collimator cone system mainly for fractionated stereotactic radiation therapy use with our innovative ideas. The new cones' mechanical accuracy and physical properties were satisfactory for clinical use, and the verification of the isocenter accuracy on the actual treatment setup has become possible.

Effects of Ginkgo biloba extract on the cochlear damage induced by local gentamicin installation in guinea pigs

Investigations evaluating the protective effect of Ginkgo biloba extract (EGb) on gentamicin (GM) ototoxicity were undertaken. Guinea pigs treated with 5 mg/kg gentamicin sulfate on the round window niche (RWN) showed acute changes on electrocochleogram and hair cell or microvilli damage on scanning electron microscopy (SEM). There was accumulation of GM in the whole cochlea, especially in the organ of Corti, stria vascularis, and type III fibrocyte on immunohistochemical study. However, the guinea pigs pretreated with local or systemic EGb revealed no significant changes by local GM installation. From these results, we concluded that EGb has a protective effect on the development of GM ototoxicity in the cochlea.

Effect of customized small bowel displacement system in pelvic irradiation

PURPOSE

Authors designed a customized small bowel displacement system (SBDS) to displace the small bowel out of the pelvic radiation fields and to minimize treatment related bowel morbidity.

METHODS AND MATERIALS

From August 1995 to May 1996, 55 consecutive patients who received pelvic radiation therapy with the SBDS were included in this study. The SBDS consists of a customized Styrofoam compression device that can displace the small bowel out of the radiation fields and an individualized immobilization abdominal board for easy daily setup of the patient in prone position. After opacifying the small bowel with barium, the patients were laid prone and posterior-anterior (PA) and lateral (LAT) simulation films were taken with and without the SBDS. The volume of the small bowel included in the radiation fields with and without the SBDS were compared.

RESULTS

Using the SBDS, the mean small bowel volume was reduced by 59% on PA and 51% on LAT films (p = 0.0001). In six patients (6 of 55, 11%), it was possible that no small bowel was included within the treatment fields. The mean upward displacement of the most caudal small bowel was 4.8 cm using the SBDS. Patients treated with the SBDS manifested a significantly lower incidence of diarrhea requiring medication (8 of 55, 15%) vs. those without the SBDS (24 of 39, 62%) (p < 0.05).

CONCLUSION

The SBDS is a novel method that can be used to displace the small bowel away from the treatment portal effectively and to reduce the radiation therapy morbidity. Compliance with setup is excellent.

Secondary angiosarcoma following irradiation--case report and review of the literature

Angiosarcoma is a rare malignant tumor that accounts for 1% to 2% of all soft tissue sarcomas. This paper reports a case of radiation-associated angiosarcoma with a literature review of 66 cases. Twenty-nine years after transabdominal hysterectomy and adjuvant radiation therapy for uterine cervix cancer, cutaneous angiosarcoma developed in the abdominal wall of a 63-year-old woman. She underwent wide excision of the abdominal wall mass, radiation therapy, and chemotherapy, and has been alive and well without any evidence of metastasis for 23 months since the initial diagnosis of angiosarcoma. After an intensive literature review, we found 66 cases of radiation-associated angiosarcoma. The most common primary disease was breast cancer (44%), with gynecologic cancer (21%) next. Eighty-five percent of radiation-associated angiosarcomas developed in the cutaneous area. The median age at diagnosis was 65 years, and the median latency period from irradiation to diagnosis was 96 months. The median survival period of 48 patients whose survival lengths could be reviewed was 12 months.

Nonparametric tests for comparing umbrella pattern treatment effects with a control in a randomized block design

This paper treats the problem of comparing umbrella pattern treatment effects with a control in a randomized block design. An extension of the Chen-Wolfe test (1993, Biometrics 49, 455-465) and its modification are proposed for both cases where the peak of the umbrella is known or unknown. Approximate critical values are given and the results of a Monte Carlo power study are presented.