Can pretreatment CT predict local control of T2 glottic carcinomas treated with radiation therapy alone?

PURPOSETo determine whether pretreatment CT can predict local control of T2 squamous cell carcinoma of the glottic larynx treated with radiation therapy alone.METHODSPretreatment CT studies were retrospectively evaluated by two head and neck radiologists in 28 patients with T2 squamous cell carcinoma of the glottic larynx treated with definitive radiation therapy. All patients were followed for a minimum of 2 years. A tumor score was calculated based on the CT findings of tumor involvement of the following areas: the anterior commissure, the contralateral true vocal cord, the arytenoid face, the interarytenoid region, the laryngeal ventricle, the paraglottic space at the true and false vocal cord levels, and the subglottic region. Tumor volumes based on pretreatment CT were measured in each patient using a computer digitizer. Statistical analysis was performed using the independent sample t test, Wilcoxon''s rank sum test, and Fisher''s Exact Test.RESULTSThere was no statistically significant relationship between tumor volume or tumor score and outcome of the T2 glottic tumors treated with definitive radiation therapy in this series. The overall local control rate was 82%. There were no treatment complications that resulted in loss of laryngeal function.CONCLUSIONSLike low-volume supraglottic and T3 glottic carcinomas, T2 glottic squamous cell carcinoma is likely (82%) to be controlled with definitive radiation therapy. Failure to control the primary tumor is attributable to factors other than volume, which may not be detectable on CT, such as tumor-host biological factors. Pretreatment CT, however, is beneficial for detecting submucosal spread across the ventricle and subglottic extension, which might contraindicate vertical hemilaryngectomy and might not be apparent on endoscopic examination.     

Early glottic squamous cell carcinoma. Predictive value of MR imaging for the rate of 5-year local control with radiation therapy

Purpose:
To evaluate MR findings in early (T1 and T2 stages) glottic carcinomas and the predictive value of MR imaging for the rate of 5-year local control with radiation therapy.
Material and Methods:
Eighty-three patients with early glottic carcinomas were prospectively examined with MR at 1.5 T. MR investigation included unenhanced T1-weighted, T2-weighted, dynamic and contrast-enhanced T1-weighted images. Three patients with presumed advanced diseases on MR were initially treated with total laryngectomy and were excluded from the study. The remaining 80 patients were treated with radiation therapy with curative intent. Tumor detectability, size and relationship to the thyroid cartilage were determined on MR images. The MR findings were then correlated with the rate of local control.
Results:
Forty-eight of 80 lesions (60%) were detected on MR imaging. All detected lesions but 1 demonstrated increased signal on T2-weighted images. The lesions were best delineated on dynamic images (statistically significant). The 5-year local control rate with radiation therapy was 72%. Univariate analysis revealed clinical T stage, MR detectability, tumor size and relationship to the thyroid cartilage as significant predictors. Multivariate analysis revealed that the relationship to the thyroid cartilage was an independent factor.
Conclusion:
MR provides prognostic information about the results of definitive radiation therapy. To evaluate the tumor extension in lesions detected on precontrast MR images, contrast-enhanced dynamic images should be obtained.     

Stage T1 glottic carcinoma: results of radiation therapy or laser excision

A retrospective analysis was made of the data on 60 patients with stage T1 glottic carcinoma (43 T1a, 17 T1b) who received radiation therapy and 17 patients with T1a disease who underwent laser excision as the primary treatment modality. Patients who received radiation therapy achieved 3- and 5-year actuarial local control rates of 92% and 89% for T1a and 77% and 77% for T1b disease, respectively. In patients who underwent laser excision (all with T1a disease), the 3-year local control rate was 77%. Of the 42 evaluable irradiated T1a patients, 31 (74%) had a normal to near-normal voice, eight (19%) had mild or intermittent hoarseness, and three (7%) had persistent hoarseness. Of the 13 evaluable patients in the laser-excision group, four (31%) had a normal to near-normal voice, five (38%) had mild or intermittent hoarseness, and four (31%) had persistent hoarseness. The difference in the quality of voice between these two groups is statistically significant (P = .012), although the ultimate local control rate after salvage therapy for irradiated patients (97%) was similar to that for laser-excision patients (94%).     

Resectable esophageal carcinoma: local control with neoadjuvant chemotherapy and radiation therapy.

PURPOSE: To evaluate the usefulness of neoadjuvant chemotherapy and radiation therapy before esophagectomy for invasive cancer of the esophagus or gastroesophageal junction (GEJ). MATERIALS AND METHODS: The authors conducted a retrospective analysis of 154 patients who underwent esophagectomy for invasive cancer between September 1, 1991, and December 31, 1995. The end points evaluated were overall, disease-free, local-regional relapse-free, and systemic relapse-free survival. RESULTS: Seventy of the 154 patients received neoadjuvant combined-modality therapy (CMT) consisting of concurrent cisplatin and fluorouracil administration and accelerated, hyperfractionated radiation therapy. The remaining 84 patients underwent immediate esophagectomy. With a median follow-up of 34.7 months, the 3-year overall, disease-free, and distant metastatic relapse-free survival rates were 38.0%, 41.9%, and 56.0%, respectively. Although neoadjuvant therapy did not appear to prevent distant metastases, there was a dramatic effect on local control. After CMT, the 5-year local control rate was 90% compared to 64% after surgery (P < .001). Tumors in the GEJ recurred more frequently (P = .01); however, multivariate analysis showed CMT was the only independent predictor of local control. Postoperative mortality was 15.7% after CMT versus 5.9% without CMT (P = .05). CONCLUSION: Local control of esophageal cancer is excellent following neoadjuvant chemotherapy and radiation therapy. However, the effects of CMT on overall and disease-free survival are less clear due to significant differences between the treatment groups.     

Bilateral stage Ib glottic carcinoma: results of radiation therapy

Bilateral early carcinoma of the true vocal cords (stage T1bN0M0) makes up about 15% of all stage I carcinomas. Twenty-four patients with stage Ib glottic carcinoma (18 with involvement of the anterior commissure and six without) received a radical course of radiation therapy with the median dose of 6,600 rad (66 Gy) in 33 fractions calculated at midpoint. In 19 patients (80%) radiation therapy alone produced complete local control of the disease. In the five patients in whom treatment failed, the recurrent tumors were confined to the larynx and were noticed within 3 years of treatment. Surgery was subsequently performed in three of the five patients but was successful in only one. In 19 of the 24 patients, the voice sounded relatively normal after radiation therapy.     

胃癌的CT诊断及其价值

目的：通过对胃癌ＣＴ表现的分析,评价ＣＴ对胃癌的诊断能力及价值。方法：患共１３例,经ＣＴ检查诊断为胃恶性肿瘤,５例诊断为胃癌,８例误诊为胃淋巴瘤或胃平滑肌肉瘤,经手术和病理均确诊为胃癌。本对患的ＣＴ表现与手术病理进行对照分析。结果：ＣＴ清楚地观察胃癌病变的全貌,病变与周围脏器的关系,但显示腹部淋巴结转移及胃癌的定性方面有一定的局限性。     

Results of radiation therapy in early glottic carcinoma: multivariate analysis of prognostic and radiation therapy variables.

A detailed retrospective analysis was performed with 103 patients who had T1 carcinoma of the glottic larynx and underwent radiation therapy between 1960 and 1987. Prognostic and radiation therapy variables were analyzed including sex; age; staging procedures; mucosal extent; histologic grading of tumor; field size; use of wedges; treatment of alternate fields versus both fields every day; nominal standard dose; time, dose, and fraction; dose per fraction; total radiation dose per fraction; total radiation doses; and the impact of cord stripping. Initial local control was 89%, and ultimate control after surgical salvage was 97%, with a 5- and 10-year adjusted survival of 98%. Univariate analysis indicated that larger field size (P = .04), histologic grade (P = .02), and treatment strategy (P = .08) were of some value in predicting recurrence. Multivariate analysis indicated that field size (P = .03) was the only significant variable in predicting local recurrence. These data confirm that radiation is highly effective in the treatment of early laryngeal cancer.     

Radiation therapy for early glottic carcinoma (T1N0M0)

Purpose

Clarification of the adverse effects of treatment interruption on the local control of early glottic carcinoma.

Patients and Methods

From May 1982 through February 1992, 273 patients with early glottic carcinoma (T1N0M0) were treated at this department. Of 253 patients administered 60 Gy in 30 fractions 77 patients had no treatment interruption and treatment was completed within 6 weeks (group I), overall treatment time was prolonged for 176 patients: 141 patients 43 to 49 days (group II) and 35 patients 50 to 62 days (group III). Treatment was interrupted due to public holidays (156 cases), patient convenience (13 cases) and severe mucosal reactions (seven cases). The major reason was public holidays, 91% in group II and 89% and group III 80%. Survivals for groups I and II, groups II and III and groups I and III were essentially the same. At 40 Gy tumor clearance was more than 50% in the 3 groups. For complete clearance cases at 40 Gy, recurrence-free survival was essentially the same for the 3 groups although for incomplete clearance cases, statistically significant difference for groups I and III (log-rank test p=0.0004; Wilcoxon test p=0.0004) and marginally significant difference for groups II and III (p=0.0157, p=0.0045) but no difference for groups I and II (p=0.0669, p=0.0853) were noted by adjusting the p-value.

Conclusion

Prolongation of overall treatment time and tumor clearance at 40 Gy appeared to be a factor of the local control.     

Pulmonary embolism in pregnant patients: fetal radiation dose with helical CT

PURPOSE: To calculate mean fetal radiation dose from helical chest computed tomography (CT) by using maternal-fetal geometries obtained from healthy pregnant women and to compare the calculated CT doses with the fetal doses reported with scintigraphy. MATERIALS AND METHODS: Maternal-fetal geometries were determined in 23 pregnant women with varying body mass index and fetal gestational age. Monte Carlo techniques were used to estimate the dose that would be received by each fetus from CT scanning performed with the following parameters: 120 kVp; 100 mA; scanning time, 1 second per section; collimation, 2.5 mm; pitch of 1. Craniocaudal extent of the scan was 11 cm, with the most caudal section edge being 5 mm inferior to the xiphoid process. RESULTS: For helical CT, estimated mean fetal doses in micrograys at varying gestational ages were as follows: 3.3-20.2 microGy, first trimester; 7.9-76.7 microGy, second trimester; and 51.3-130.8 microGy, third trimester. These values were all less than mean fetal doses reported with scintigraphy, with 37-74 MBq of macroaggregates of human serum albumin labeled with technetium 99m. If 200 mAs (pitch of 1.8) was used, the mean fetal doses were still less than those with scintigraphy. CONCLUSION: The average fetal radiation dose with helical CT is less than that with ventilation-perfusion lung scanning during all trimesters.     

Pancreatic abscess: predictive value of early abdominal CT

The value of a recently reported grading system of early abdominal computed tomography (CT) for predicting development of pancreatic abscess in patients with acute pancreatitis was reassessed. When the previously described CT grading system was used in another patient population, it did not demonstrate the same degree of prognostic value of baseline CT. In this series pancreatic abscess occurred in only eight of 29 patients (28%) with grade E CT scans (with grade E representing the most severe involvement), compared with 60% in the previous series. Of 44 patients with either grade D or E baseline CT scans, abscesses developed in only 30%, with a minimum clinical follow-up of 3 months. A second grading system, which used a semiquantitative analysis of the degree of peripancreatic inflammation (a "CT severity score"), also did not strongly correlate with the future risk of abscess, The authors conclude that early abdominal CT should be performed selectively in patients with acute pancreatitis and reserved for patients who are either diagnostic dilemmas or who fail to respond to supportive treatment and have clinically suspected surgical complications such as pancreatic abscess.     

喉及下咽癌采用螺旋CT增强扫描及多平面重组的应用价值

目的 探讨螺旋CT增强扫描及多平面重组(MPR)在喉及下咽癌术前分期及术后评价中的临床应用价值。方法 50例喉及下咽癌患者(原发肿瘤40例、术后评价10例)进行轴位螺旋CT平扫及三期增强扫描，同时做MPR成像。将结果与纤维喉镜、手术所见对照分析。结果 螺旋CT增强扫描轴位结合MPR图像对术前肿瘤分期和诊断颈部淋巴结转移的准确性分别是95％及97.5％；25％的病例MPR显示肿瘤侵犯的范围优于轴位；增强图像有助于判断肿瘤的侵犯范围及颈部淋巴结转移，静脉期图像对肿瘤的分期帮助最大；螺旋CT三期增强扫描有利于评价喉及下咽癌的术后状况。结论 螺旋CT增强扫描轴位结合MPR图像，可以更完整地提供喉及下咽癌术前分期及术后评价的全面资料。     

Early-stage glottic cancer: importance of dose fractionation in radiation therapy.

The treatment results in 85 patients with T1N0M0 squamous cell carcinoma of the glottic larynx who were treated with primary radiation therapy were reviewed to analyze for local control. After a minimum follow-up period of 2 years, 13 patients had local recurrence of disease, which yielded a local control rate of 84.7%. Local control was then reassessed as a function of substages (T1a and T1b) and dose fractionation. No difference in local control was seen in T1a and T1b neoplasms. However, after undergoing standard once-a-day fractionation, patients treated with fractions of 200 cGy had a local control rate of 96%, while those receiving 180 cGy had a local control rate of 79% (P = .05). Mean total dose for each patient group was comparable, and the median number of days of treatment interruption was the same for both groups. These data corroborate the recent findings of other authors regarding the importance of fraction size in facilitating local control of early-stage glottic cancer.     

扫描方式对64层螺旋CT头颅CTA图像质量和辐射剂量影响的研究

目的：探讨64层螺旋CT扫描方式对头颅CTA图像质量和辐射剂量的影响。方法：采用GE Lightspeed VCT对100例需要行头颅CTA检查的患者进行对比研究,50例行螺旋扫描,另50例行轴层扫描。两组数据经过VR、MIP、去骨VR和多平面重组等方法后处理,然后由3组医师通过5分评价法对CTA图像质量进行主观评价,取其均值纳入统计学分析;记录每组扫描的容积剂量指数（CTDIvol）和剂量长度乘积（DLP）。对两组数据进行两独立样本t检验。结果：轴向扫描图像质量评分是（4．66±0．42）分、螺旋扫描CTA的成像质量评分（4．67±0．38）分;两组数据差异无统计学意义（P〉0．05）。轴向扫描、螺旋扫描的CTDIvol分别是45．71和54．18mGy;DLP分别是731．43和954．68mGy·cm。两组间差异有统计学意义（P〈0．05）,轴层扫描方式辐射剂量更低。结论：64层CT头颅CTA轴扫可以显著降低辐射剂量而不降低图像质量,在临床运用中值得关注。