Evaluation of the retentive force of a b-type Ti-6Mo-4Sn alloy wire clasp

The retentive force of a wire clasp composed of a b-type Ti-6Mo-4Sn alloy (b-Ti alloy) with a low Young modulus was evaluated using a piezoelectric transducer to determine the appropriate undercut for removable partial dentures. There were no significant differences in retentive force between a b-Ti alloy wire with a 0.50-mm undercut and a cobalt-chromium alloy (Co-Cr alloy) wire with a 0.25-mm undercut, or between a b-Ti alloy wire with a 0.75-mm undercut and a Co-Cr alloy wire with a 0.50-mm undercut. The b-Ti alloy wire may be applicable for abutment teeth with a large number of undercuts. Int J Prosthodont 2010;23:38-41.

Treatment and prognosis of brain metastases from breast cancer

BACKGROUND

To analyze retrospectively the results of treatments for patients with brain metastases from breast cancer.

MATERIALS AND METHODS

The records of 65 breast cancer patients with brain metastases who were treated between 1985 and 2005 were reviewed. For brain metastases, 11 patients (17%) were treated with surgical resection followed by radiotherapy, and the remaining 54 patients were treated with radiotherapy alone. Systemic chemotherapy was also administered to 11 patients after brain radiotherapy.

RESULTS

The overall median survival for all patients was 6.1 months (range, 0.4-82.2 months). In univariate analysis, treatment modality, Karnofsky performance status (KPS), administration of systemic chemotherapy, extracranial disease status and total radiation dose each had significant impact on overall survival, and in multivariate analysis, treatment modality, KPS and administration of systemic chemotherapy were significant prognostic factors. Eight patients survived for more than 2 years after the diagnosis of brain metastases, and all these patients were treated with surgical resection and/or systemic chemotherapy in addition to radiotherapy. For the 45 patients treated with palliative radiotherapy (without systemic chemotherapy), the improvements in neurological symptoms were observed in 35 patients (78%), with the median duration of improvement of 3.1 months (range, 1.5-4.4 months).

CONCLUSIONS

The prognoses for patients with brain metastases from breast cancer were generally poor, although selected patients may survive longer with intensive brain tumor treatment, such as surgical resection and/or systemic chemotherapy in addition to brain radiotherapy. For patients with unfavorable prognoses, palliative radiotherapy was effective in improving the quality of the remaining lifetime.

Radiation Enterocolitis Requiring Surgery in Patients With Gynecological Malignancies

PURPOSE

To identify the characteristics, risk factors, and clinical outcomes of radiation enterocolitis requiring surgery in patients with gynecologic malignancies.

METHODS AND MATERIALS

The records of 1,349 patients treated with pelvic radiotherapy were retrospectively reviewed. The majority of the patients (88%) were treated with 50 Gy or 50.4 Gy pelvic irradiation in conventional fractionations with anteroposterior fields.

RESULTS

Forty-eight patients (3.6%) developed radiation enterocolitis requiring surgery. Terminal ileum was the most frequent site (50%) and most of the lesions had stenosis or perforation. On univariate analysis, previous abdominopelvic surgery, diabetes mellitus (DM), smoking and primary site had an impact on the complications, and on multivariate analysis, abdominopelvic surgery, DM, and smoking were independent predictors of the complications requiring surgery. After the surgical intervention, the frequency of Grade 2 or more bleeding was significantly lower in patients treated with intestinal resection in addition to decompression than those treated with intestinal decompression alone.

CONCLUSIONS

Severe radiation enterocolitis requiring surgery usually occurred at the terminal ileum and was strongly correlated with previous abdominopelvic surgery, DM, and smoking. Concerning the management, liberal resection of the affected bowel appears to be the preferable therapy.

Self-expandable metallic stent placement for patients with inoperable esophageal carcinoma: investigation of the influence of prior radiotherapy and chemotherapy

PURPOSE

The aim of this study was to evaluate the efficacy and complications of self-expandable metallic stent placement for patients with inoperable esophageal carcinoma after radiotherapy and/or chemotherapy.

MATERIALS AND METHODS

We obtained data from 19 patients with advanced or recurrent esophageal carcinoma between 1996 and 2000. In all patients, a self-expandable metallic stent was placed under fluoroscopic guidance. Dysphagia before and after stent placement was graded. Complications after stent placement were also evaluated. Data were compared between patients with and without prior radiotherapy and/or chemotherapy.

RESULTS

The procedure was technically successful in all but one patient. The dysphagia grade improved in all patients. No life-threatening complications occurred. The other major complications such as mediastinitis occurred in two patients, and pneumonia and funnel phenomenon occurred in one patient each. These patients had a history of radiotherapy and/or chemotherapy prior to stent placement. Eight of the twelve patients with prior radiotherapy and/or chemotherapy compared with one of seven patients without prior therapy had persistent chest pain, which was a statistically significant difference (P < 0.05).

CONCLUSION

Placement of self-expandable metallic stents was effective for patients with advanced or recurrent esophageal carcinoma. However, prior irradiation and/or chemotherapy increased the risk of persistent chest pain after stent placement.

Phase II trial of radiotherapy after hyperbaric oxygenation with chemotherapy for high-grade gliomas

We conducted a phase II trial to evaluate the efficacy and toxicity of radiotherapy immediately after hyperbaric oxygenation (HBO) with chemotherapy in adults with high-grade gliomas. Patients with histologically confirmed high-grade gliomas were administered radiotherapy in daily 2 Gy fractions for 5 consecutive days per week up to a total dose of 60 Gy. Each fraction was administered immediately after HBO with the period of time from completion of decompression to irradiation being less than 15 min. Chemotherapy consisted of procarbazine, nimustine (ACNU) and vincristine and was administered during and after radiotherapy. A total of 41 patients (31 patients with glioblastoma and 10 patients with grade 3 gliomas) were enrolled. All 41 patients were able to complete a total radiotherapy dose of 60 Gy immediately after HBO with one course of concurrent chemotherapy. Of 30 assessable patients, 17 (57%) had an objective response including four CR and 13 PR. The median time to progression and the median survival time in glioblastoma patients were 12.3 months and 17.3 months, respectively. On univariate analysis, histologic grade (P=0.0001) and Karnofsky performance status (P=0.036) had a significant impact on survival, and on multivariate analysis, histologic grade alone was a significant prognostic factor for survival (P=0.001). Although grade 4 leukopenia and grade 4 thrombocytopenia occurred in 10 and 7% of all patients, respectively, these were transient with no patients developing neutropenic fever or intracranial haemorrhage. No serious nonhaematological or late toxicities were seen. These results indicated that radiotherapy delivered immediately after HBO with chemotherapy was safe with virtually no late toxicity in patients with high-grade gliomas. Further studies are required to strictly evaluate the effectiveness of radiotherapy after HBO for these tumours.

Hyperfractionated radiotherapy and multi-agent chemotherapy (procarbazine, ACNU and vincristine) for high-grade gliomas: a prospective study

AIM

To evaluate the feasibility, efficacy and toxicity of hyperfractionated radiotherapy and multi-agent chemotherapy, including procarbazine, nimustine (ACNU) and vincristine, in adults with high-grade gliomas.

MATERIALS AND METHODS

Radiotherapy was administered using two fractions per day of 1.2 Gy to a total dose of 72 Gy. The chemotherapy consisted of procarbazine (90 mg/m2 orally, days 1 to 14), ACNU (80 mg/m2 intravenously, day 1) and vincristine (0.5 mg/m2 intravenously, days 1 and 8) and was administered during and after radiotherapy, up to a maximum of four courses.

RESULTS

From September 1997 to August 1999, a total of ten patients (five with glioblastoma and five with grade 3 gliomas) were enrolled. All ten patients were able to complete a total dose of 72 Gy hyperfractionated radiotherapy with one course of concurrent chemotherapy. Of eight assessable patients, three (38%) had an objective response, comprising two CR and one PR. The median time to progression was 10.7 months and the median survival time of all patients was 15.0 months. Although grade 4 leukopenia and grade 4 thrombocytopenia occurred in 10% and 10% of all patients, respectively, these were transient and no patients developed neutropenic fever or intracranial hemorrhage. No serious non-hematological or late toxicities occurred.

CONCLUSION

Hyperfractionated radiotherapy and multi-agent chemotherapy using procarbazine, ACNU and vincristine is safe and well tolerated for high-grade gliomas.

Risk Factor of Radiation Pneumonitis

OBJECTIVE

The aim of this study was to investigate whether the pulmonary arterial flow obtained as a function of time from velocity-encoded cine (VEC) magnetic resonance (MR) imaging can be used to predict radiation pneumonitis.

METHODS

Before receiving radical radiotherapy, 19 patients with primary lung cancer and 21 with primary esophageal cancer underwent VEC MR imaging to determine their pulmonary arterial flow. The right and left pulmonary arterial flow profiles were digitized, and from these data, acceleration time, maximal change in flow rate during ejection, acceleration volume, and the ratio of maximal change in flow rate during ejection to acceleration volume were measured. The statistical significance of differences in pulmonary arterial flows before irradiation between patients who developed and did not develop RP greater than grade 1 was determined.

RESULTS

Radiation pneumonitis occurred in 5 patients with lung cancer and in 4 with esophageal cancer. The acceleration time (P < 0.001), acceleration volume (P < 0.02), and ratio of the maximal change in flow rate during ejection to acceleration volume (P < 0.002) in patients with and without RP were significantly different. The sensitivity, specificity, and accuracy of using 111 milliseconds as the cutoff value (which was the mean acceleration time in the RP group) to predict RP were 58%, 88%, and 83%, respectively.

CONCLUSIONS

Pulmonary hypertension detected by VEC MR imaging can be a risk factor for development of RP in candidates for pulmonary irradiation.

Combination external beam radiotherapy and high-dose-rate intracavitary brachytherapy for uterine cervical cancer: analysis of dose and fractionation schedule

PURPOSE

To determine an appropriate dose and fractionation schedule for a combination of external beam radiotherapy (EBRT) and high-dose-rate intracavitary brachytherapy (HDR-ICBT) for uterine cervical cancer.

METHODS

Eighty-eight patients with uterine cervical squamous cell carcinoma treated with EBRT and HDR-ICBT were analyzed. Twenty-five patients were classified as early disease (nonbulky Stage I/II, less than 4-cm diameter) and 63 patients as advanced disease (greater than 4 cm diameter or Stage IIIB) according to the American Brachytherapy Society definition. Tumor diameter was measured by MRI. Pelvic EBRT was delivered before applications of ICBT. HDR-ICBT was performed once a week, with a fraction point A dose of 6 Gy. Source loadings corresponded to the Manchester System for uterine cervical cancer. No planned optimization was done. A Henschke-type applicator was mostly used (86%). Median cumulative biologic effective dose (BED) at point A (EBRT + ICBT) was 64.8 Gy(10) (range: 48-76.8 Gy(10)) for early disease, and 76.8 Gy(10) (range: 38.4-86.4 Gy(10)) for advanced disease. Median cumulative BED at ICRU 38 reference points (EBRT + ICBT) was 97.7 Gy(3) (range: 59.1-134.4 Gy(3)) at the rectum, 97.8 Gy(3) (range: 54.6-130.4 Gy(3)) at the bladder, and 324 Gy(3) (range: 185.5-618 Gy(3)) at the vagina. Actuarial pelvic control rate and late complication rate were analyzed according to cumulative dose and calculated BED.

RESULTS

The 3-year actuarial pelvic control rate was 82% for all 88 patients: 96% for those with early disease, and 76% for advanced disease. For pelvic control, no significant dose-response relationship was observed by treatment schedules and cumulative BED at point A for both early and advanced disease. The 3-year actuarial late complication rates (Grade > or =1) were 12% for proctitis, 11% for cystitis, and 14% for enterocolitis. There were significant differences on the incidence of proctitis (p < 0.0001) and enterocolitis (p < 0.0001), but not for cystitis by the treatment schedules and cumulative point A BED. All 4 patients treated with 86.4 Gy(10) at point A suffered both proctitis and enterocolitis. Patients with cumulative BED at rectal point of > or =100 Gy(3) had significantly higher incidence of proctitis (31% vs. 4%, p = 0.013).

CONCLUSIONS

In view of the therapeutic ratio, cumulative BED 70-80 Gy(10) at point A is appropriate for uterine cervical cancer patients treated with a combination of EBRT and HDR-ICBT. Present results and data from other literatures suggested that cumulative BED at the rectal point should be kept below 100-120 Gy(3) to prevent late rectal complication.

Prospective trial of radiotherapy after hyperbaric oxygenation with chemotherapy for high-grade gliomas

Twenty-one patients with high-grade gliomas were enrolled in a prospective trial of radiotherapy after hyperbaric oxygenation (HBO). Radiotherapy was administered in daily 2-Gy fractions up to a total dose of 60 Gy, and each fraction was delivered immediately after HBO. The current study indicated that radiotherapy immediately after HBO with chemotherapy was feasible for high-grade gliomas.

Treatment and prognosis of thymic carcinoma: a retrospective analysis of 40 cases

BACKGROUND

Thymic carcinomas are rare neoplasms, and information regarding the results of treatment and possible prognostic factors in patients with these tumors is limited.

METHODS

The records of 40 patients with histologically confirmed thymic carcinoma who were treated between 1984 and 1998 were reviewed. Twenty-seven patients were treated with surgical resection followed by radiotherapy with or without chemotherapy, and the remaining 13 patients were treated with radiotherapy with or without chemotherapy. The median follow-up time for the 13 surviving patients was 87 months (range, 44-193 months).

RESULTS

The 5-year and 10-year actuarial overall survival rates in all patients were 38% and 28%, respectively. On univariate analysis, complete resection, Karnofsky performance status (KPS), histology, and Masaoka stage at the time of diagnosis were found to have a significant impact on overall survival, whereas on multivariate analysis, complete resection, KPS, and histology were found to be significant prognostic factors. With regard to the degree of resection, 12 of 16 patients (75%) treated with complete resection were alive and free of disease at the time of last follow-up whereas 1 of 24 patients (4%) treated with incomplete resection or biopsy still was alive. Among 12 surviving patients treated with complete resection, 8 with resectable tumors at the time of presentation all had low-grade histology (squamous cell carcinoma) and were treated successfully with complete resection and postoperative radiotherapy with or without adjuvant chemotherapy. The remaining four patients with unresectable tumors at the time of presentation were treated successfully with neoadjuvant chemotherapy, complete resection, and postoperative radiotherapy.

CONCLUSIONS

The results of the current study indicate that multimodal treatment, especially complete resection and postoperative radiotherapy with or without chemotherapy, is a curative therapy for thymic carcinomas.

Postoperative radiotherapy for patients with completely resected thymoma: a multi-institutional, retrospective review of 103 patients

BACKGROUND

Optimal management of postoperative radiotherapy for patients with completely resected thymoma remains controversial. This study was conducted to assess the efficacy of postoperative mediastinal irradiation in patients with completely resected thymoma.

METHODS

The records of 103 patients with completely resected thymoma who received postoperative mediastinal irradiation during the period between 1979 and 1998 were reviewed. The distribution according to Masaoka stage was Stage I in 17 patients, Stage II in 61 patients, and Stage III in 25 patients. Fifty-two patients were treated with involved field (IF) irradiation, and 51 patients were treated with irradiation of the whole mediastinal field with or without boost (WM irradiation). The total radiation dose to the primary tumor bed was 30-61 grays (Gy), with a median dose of 40 Gy. No patients received chemotherapy during the initial treatment. The median follow-up of the 82 living patients was 112 months (range, 24-244 months).

RESULTS

The 10-year actuarial overall and disease free survival rates for all patients were 81% and 79%, respectively. The 10-year actuarial overall survival rate was 100% for patients with Stage I disease, 90% for patients with Stage II disease, and 48% for patients with Stage III disease. In the analysis, clinical stage alone had a statistically significant impact on both overall survival and disease free survival (P < 0.0001 for both). Recurrent disease was observed in 17 patients, and the pleura was the most frequent site of first recurrence. Of 12 patients who had pleural recurrences, 11 patients had pleural dissemination remote from the initial tumor site. No recurrence was observed in any of the 17 patients with Stage I disease, and 6 of 61 patients (10%) with Stage II disease and 11 of 25 patients (44%) with Stage III disease experienced recurrences. With regard to intrathoracic recurrences, there were no recurrences within the irradiated field in any of the 103 patients, and no dose response correlation was seen in intrathoracic control (incidence of intrathoracic recurrence: 2 of 19 patients in the group that received < 40 Gy, 6 of 45 patients in the group that received 40 Gy, and 7 of 39 patients in the group that received > 40 Gy). With respect to treatment field, mediastinal recurrences were observed in 4 of 52 patients (8%) who were treated with IF irradiation, whereas 0 of 51 patients who were treated with WM irradiation experienced mediastinal recurrences. Pleural-based recurrences were observed both in patients who were treated with IF irradiation (7 of 52 patients) and in patients who were treated with WM irradiation (5 of 51 patients). According to the degree of pathologic tumor invasion, 0 of 71 patients without pleural invasion had pleural-based recurrences (0 of 17 patients with Stage I disease, 0 of 51 patients with Stage II disease, and 0 of 3 patients with Stage III disease), whereas 12 of 32 patients (38%) with pleural invasion had pleural-based recurrences (4 of 10 patients with Stage II disease and 8 of 22 patients with Stage III disease).

CONCLUSIONS

The current results indicated that WM irradiation with a total dose of 40 Gy was effective in preventing mediastinal recurrence for patients with completely resected thymoma. However, in patients with pathologic pleural invasion of the tumor, mediastinal irradiation alone was insufficient to avoid pleural-based recurrence.

Brain metastases from esophageal carcinoma: natural history, prognostic factors, and outcome

BACKGROUND

Brain metastases from esophageal carcinoma are extremely rare, and information regarding the natural history, results of treatment, and possible prognostic factors in these patients is limited.

METHODS

The records of 36 patients with brain metastases from esophageal carcinoma who were treated between 1986 and 2000 were reviewed. For brain metastases, 12 patients (33%) were treated with surgical resection followed by radiation therapy (S+RT), and the remaining 24 patients were treated with radiation therapy alone.

RESULTS

At the initial diagnosis of esophageal carcinoma, the median primary tumor length was 8 cm (range, 2-19 cm), and 26 of 32 available patients (81%) had clinical Stage III-IV tumors according to the International Union Against Cancer 1997 criteria. At time brain metastases appeared, lung metastases were not demonstrated in 25 of 36 patients (69%) who were assessed by chest computed tomography (CT) scans. The overall median survival for all patients was 3.9 months (range, 0.6-36.8 months), and the actuarial survival rates at 12 months and 24 months were 14% and 3%, respectively. In univariate analysis, treatment modality, Karnofsky performance status (KPS), and extracranial disease status each had a statistically significant impact on survival, and, in multivariate analysis, treatment modality and KPS were statistically significant prognostic factors for survival. Five patients (14%) survived more than 1 year, all of whom were treated with S+RT. These five patients had inactive extracranial disease and, four of five patients (80%) had a 90-100% KPS.

CONCLUSIONS

Brain metastases from esophageal carcinoma tended to occur in patients with a large primary tumors and/or disease in advanced clinical stages. With the appearance of brain metastases, an absence of lung metastasis frequently was observed on chest CT scans. The prognoses for these patients were generally poor, although selected patients may survive longer with intensive brain tumor treatment.

Concurrent chemoradiotherapy for squamous cell carcinoma of thoracic esophagus: feasibility and outcome of large regional field and high-dose external beam boost irradiation

OBJECTIVE

To assess the feasibility and outcome of concurrent chemoradiotherapy (CT-RT) with large regional field and high-dose external beam boost irradiation in thoracic esophageal cancer.

METHODS

Patients with clinical stage T1 (submucosal)-4N0-1M0 (UICC 1997) squamous cell carcinoma of the thoracic esophagus were eligible. Radiotherapy consisted of regional irradiation (extending from supraclavicular fossa to the paracardial area) with 39.6 Gy followed by high-dose external beam boost up to 66.6 Gy (1.8 Gy/day, five times per week). Two-hour infusion of cisplatin (80 mg/m(2) on day 1) and continuous infusion of 5-fluorouracil (800 mg/m(2)/day on days 2-6) were administered concurrently with radiotherapy, every 3-4 weeks, for two cycles.

RESULTS

Thirty patients (stage I, 3; stage II, 11; stage III, 16) were entered into the study. Twenty-one patients (70%) completed the planned treatment. In elderly (> or = 70 years) patients, four of six withdrew. Grade 3 and 4 toxicities (NCI-CTC) were observed in 20 (67%) and three (10%) patients, respectively. Major toxicities were blood, gastrointestinal (i.e. nausea and esophagitis) and pulmonary. There was no grade 5 (fatal) toxicity. The median follow-up period for surviving patients was 27 months (range: 9-49 months). The median survival time was 21 months. The 1- and 2-year survival rates were 65 and 49% for all 30 patients. The incidence of esophageal stricture (grade 1-2: RTOG) was 21%. No patient suffered fistula formation.

CONCLUSIONS

Despite poor compliance for elderly patients and frequent severe toxicities, our concurrent CT-RT resulted in a favorable outcome in thoracic esophageal cancer.

Postoperative radiotherapy for squamous cell carcinoma of the maxillary sinus: analysis of local control and late complications

This retrospective study was conducted to analyze the local control and late complications in patients with squamous cell carcinoma of the maxillary sinus treated with postoperative radiation therapy following surgery. Between 1979 and 1998, 41 patients with squamous cell carcinoma of the maxillary sinus were treated with postoperative irradiation following partial or total maxillectomy. Tumor classification according to the TNM classification of the International Union Against Cancer (1997) was T2 in 6 patients, T3 in 21 patients, and T4 in 14 patients. Fourteen patients had negative surgical margins, 23 had microscopically positive margins, and 4 had grossly positive margins. Sixteen patients received preoperative intraarterial chemotherapy. The total dose to the primary tumor bed was 40-70 Gy (median: 54 Gy) with a fraction size of 2 Gy. The median follow-up time of the surviving patients was 93 months (range: 25-179 months). Local recurrence was observed in 17 patients (41%), and the 5-year actuarial overall survival and local control rates were 48% and 55%, respectively. In the univariate analysis, surgical margin status and total dose each had a statistically significant impact on local recurrence. For the patients with negative surgical margins, 8 of 9 (89%) patients achieved local control with a dose of 50-54 Gy, while 7 of 10 (70%) patients with microscopically positive margins achieved local control with a dose of 60-64 Gy. There were 11 late complications found in 9 patients; bone necrosis in 2, soft tissue necrosis in 2, trisumus: 2, cellulitis in 1, retinopathy in 1, and vision impairment in 3 patients. A total dose of 60 Gy or more was administered in all patients who suffered late complications except for 2 patients with vision impairment. These results indicated that an optimal dose of postoperative irradiation according to the surgical margin status was necessary to achieve local control for squamous cell carcinoma of the maxillary sinus following surgery. For patients with negative surgical margins, a total dose of 50-54 Gy in conventional fractionation was appropriate to achieve local control as well as to reduce late complications. On the other hand, a dose of 60 Gy or more was required for the patients with microscopic positive margins.

Radiation therapy following mastectomy for axillary node-positive breast cancer: indication of chest wall irradiation

This retrospective study was conducted to determine the indication of chest wall irradiation following mastectomy in axillary node-positive breast cancer patients. Between 1982 and 1993, 103 women with axillary node-positive breast cancer received postoperative radiation therapy following mastectomy using the hockey-stick field, which included the ipsilateral supraclavicular fossa and internal mammary nodes, without the chest wall. Ages ranged from 33 to 73 years (median: 47). Thirty-five patients underwent modified radical mastectomy, 48 radical mastectomy, and 20 extended radical mastectomy. Twenty-two patients had 1-3 positive axillary nodes, and 81 had 4 or more positive axillary nodes. The total doses ranged from 42 to 64 Gy (median 54 Gy) with a daily fraction size of 2 Gy. Adjuvant chemotherapy was given to 75 patients, and hormone therapy was administered to 78 patients. The median follow-up time was 121 months (range, 68-191 months) for the 57 surviving patients. The actuarial overall survival rate and the chest wall control rate at 10 years for all patients were 55% and 85%, respectively. Of the 103 patients, 14 developed chest wall recurrence. In the analysis, status of vascular invasion alone had a significant impact on chest wall control. In patients with definite vascular invasion, 2 of 5 (40%) patients with 1 to 3 positive axillary nodes, and 10 of 31 (32%) with 4 or more positive axillary nodes developed chest wall recurrence. In contrast, no patients without definite vascular invasion developed chest wall recurrence. Factors such as age, menopausal status, pathology, tumor location, extent of resection, estrogen receptor status, total dose, chemotherapy, and hormone therapy did not influence the development of chest wall recurrence. Among node-positive breast cancer patients following mastectomy, those with definite vascular invasion should be delivered chest wall irradiation regardless of the number of positive axillary nodes. In contrast, those without definite vascular invasion need not be administered chest wall irradiation.

Thermal Transformation in Anhydrous Rare Earth Acetates

The thermal transformation in anhydrous acetates of Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu, and Y has been studied by thermal analysis. The enthalpy change, ΔH, and the entropy change, ΔS, accompanying the transformation process are reported and related to ionic radius of the rare earth element.The acetates of the rare earth elements, La, Pr, and Nd did not exhibit the thermal transformation property.