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AJR 2004; 182:1123-1128
© American Roentgen Ray Society


Radiation Injury After Hypofractionated Stereotactic Radiotherapy for Peripheral Small Lung Tumors: Serial Changes on CT

Toshiaki Takeda1, Atsuya Takeda1, Etsuo Kunieda1,2, Akitoshi Ishizaka3, Kazuhiko Takemasa1, Kyoko Shimada1, Seika Yamamoto1, Naoyuki Shigematsu2, Osamu Kawaguchi2, Jun-ichi Fukada1,2, Toshio Ohashi2, Sachio Kuribayashi2 and Atsushi Kubo2

1 Department of Radiology, Tokyo Metropolitan Hiro-o General Hospital, 2-34-10 Ebisu, Shibuya-ku, Tokyo 150-0013, Japan.
2 Department of Radiology, School of Medicine, Keio University, 35 Shinanomachi, Shinkuku-ku, Tokyo 160-8582, Japan.
3 Department of Medicine, School of Medicine, Keio University, Tokyo 160-8582, Japan.

Received June 16, 2003; accepted after revision November 10, 2003.

 
Address correspondence to T. Takeda (t-takeda{at}hiroo-hospital.metro.tokyo.jp).


Abstract
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Abstract
Introduction
Subjects and Methods
Results
Discussion
References
 
OBJECTIVE. We studied the serial changes and CT manifestations of pulmonary radiation injury after hypofractionated stereotactic radiation therapy for peripheral small lung tumors.

SUBJECTS AND METHODS. Hypofractionated stereotactic radiation therapy was applied to 20 patients with proven primary (n = 11) or metastatic (n = 9) lung cancer, for a total of 22 lesions of 3 cm or less in diameter located within 3 cm from the parietal pleural surface. Follow-up CT was scheduled at 1 and 3 months, and every 3 months thereafter.

RESULTS. Ground-glass opacities were observed around four (18%) of 22 lesions at 3–6 months. The opacities nearly corresponded to the planned target volume, but half of them were unevenly distributed. Ground-glass opacities gradually disappeared or evolved into dense consolidation while shrinking. Dense consolidations developed in 16 (73%) of 22 lesions, including seven in the center of the planned target volume and nine in the periphery of the planned target volume. Dense consolidations moved in six of these 16 lesions and gradually shrank, becoming fixed as solid or linear opacities approximately 12 months later.

CONCLUSION. The pulmonary opacities observed after hypofractionated stereotactic radiation therapy for peripheral small lung tumors may not precisely correspond to the planned target volume (unlike those with conventional radiation therapy) and may change in shape and location dynamically during the first year. Knowledge of these findings is necessary to avoid misunderstandings concerning tumor regrowth or new tumors.


Introduction
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Abstract
Introduction
Subjects and Methods
Results
Discussion
References
 
Currently, surgery is the treatment of choice in the early stages of lung cancer. Although conventional radiation therapy may be selected as a less invasive intervention in elderly patients and in those with inoperable disease, the rate of local control of malignancy after radiation therapy is approximately 30%, which is lower than for surgical resection [1]. Stereotactic irradiation can deliver high radiation doses to localized lesions with great accuracy, allowing a strong antitumoral effect while lessening radiation injury to normal tissues [2]; it has been applied to the treatment of small intracranial tumors with excellent results [2]. More recently, hypofractionated stereotactic radiotherapy has been applied to the treatment of extracranial malignant tumors, with preliminary studies reporting greater than 90% control rates for small localized lung tumors [35].

In this study, we applied hypofractionated stereotactic radiotherapy to the treatment of small lung tumors and observed the various radiologic patterns of change after irradiation. As indicated by previous reports [6, 7], radiation injuries caused by conventional coplanar radiotherapy show distinct linear margins on CT that correspond to the margins of the irradiation field. However, because hypofractionated stereotactic radiotherapy is delivered in a 3D spherical volume with a steep gradient between the periphery of the planned target volume and normal adjacent tissue, the shape of the radiation injury should be considered three-dimensionally. Hypofractionated high-dose irradiation, with highly concentrated narrow beams that target small volumes, is associated with markedly different dose distributions and biologic effects on tissues from those described for coplanar conventional radiotherapy. The aim of this study was to describe the CT characteristics of radiation injury after hypofractionated stereotactic radiotherapy for small lung malignancies.


Subjects and Methods
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Abstract
Introduction
Subjects and Methods
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Discussion
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The patient population consisted of 17 men and three women (age range, 56–89 years; median, 72.6 years) who were treated with hypofractionated stereotactic radiotherapy at our institutions between January 1998 and November 2002. For most patients, surgery was not indicated because of patient age, the presence of multiple lesions, or poor pulmonary function. Five patients preferred hypofractionated stereotactic radiotherapy treatment even though surgery was possible. The study protocol was approved by the institutional review boards of the institutions, and written informed consent was obtained from each participant before hypofractionated stereotactic radiotherapy was performed.

Primary lung cancer was pathologically proven in 11 patients (11 lesions), and metastases from other primary cancers were diagnosed clinically in nine patients (11 lesions). Hypofractionated stereotactic radiotherapy was generally considered if the tumor was 3 cm or smaller in diameter, if it was 3 cm or less from the parietal pleural surface, if craniocaudal breathing-associated motion of the lesion was 1 cm or less, and if three or fewer lesions were present at the start of treatment. Because the risk of atelectasis and reduction of pulmonary function caused by the collapse of large bronchi was unknown, potential lesions for treatment were limited to peripheral lesions 3 cm or less from the parietal pleural surface so that the planned target volume would not contain lobar bronchi. Tumor pathology and mean tumor volumes are listed in Table 1.


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TABLE 1 CT Manifestations of Radiation Pneumonitis

 

Pretreatment Evaluation and Radiation Treatment
The planned target volume was determined using CT (Xvision, Toshiba) performed on patients who were breathing at rest. Serial 2-mm-thick scans were obtained in 2-mm increments at 4–8 sec per slice. Longer scanning periods were used to define the tumor trajectory associated with breathing. The planned target volume consisted of the imaged volume, defined as the gross tumor volume plus an internal margin, plus a 5- to 10-mm setup margin.

Tumor volumes (V) were calculated according to the following formula:

where R1 (half the maximum diameter), R2 (half the diameter perpendicular to R1), and R3 (half the maximum diameter in the craniocaudal direction) were obtained with calipers on CT. When the tumor margin was ill defined, the outermost circumference was used. The diameter in the craniocaudal direction was defined as the product of the thickness and the number of slices from the top to the bottom of the lesion. Estimated tumor volumes ranged from 0.5 to 45.5 cm3 (mean, 9.5 cm3).

Treatments were planned using a radiation treatment planning system (FOCUS version 2.7.0, Computerized Medical Systems). Volumes to be treated were set so that the planned target volume received an 80% isodose of the maximum dose, with 80% isodose defined as the therapeutic dose (Figs. 1A, 2A, and 3A). The shape of the field was adjusted dynamically according to the tumor shape using a multileaf collimator.



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Fig. 1A. 59-year-old man with lung metastasis from rectal carcinoma. Typical characteristics of radiation pneumonitis and fibrosis after hypofractionated stereotactic radiotherapy are seen on serial lung CT scans after irradiation. Axial unenhanced CT scan obtained before treatment shows tumor in right upper lobe. PTV = planned target volume.

 


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Fig. 2A. 85-year-old man with squamous cell cancer. Axial unenhanced CT scan obtained before treatment shows cavitated tumor in left upper lobe. PTV = planned target volume.

 


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Fig. 3A. 70-year-old man with lung metastasis of oropharyngeal carcinoma. Axial unenhanced CT scan obtained before treatment shows metastatic tumor in right lower lobe. PTV = planned target volume.

 

The irradiation dose generally consisted of 50 Gy in five fractions administered over 5–7 days. Seventeen lesions in 15 patients were treated using this dose regimen. When a tumor was adjacent to critical organs (e.g., spinal cord or esophagus), the fractionated dose was reduced to 5–7 Gy and the total dose was limited to 40–50 Gy.

Radiologic Follow-Up
Patients were interviewed monthly to determine the presence or absence of symptoms and for chest roentgenographic examination.

Lesion characteristics were periodically examined on CT (Xvigor or Xvision, Toshiba) even in the absence of clinical symptoms at follow-up visits approximately 1 and 3 months after treatment, and in principle every 3 months thereafter. The interval of CT varied slightly depending on each patient's clinical status. If dubious opacities were seen on periodic radiography, additional CT was performed between the scheduled examinations. Single-slice helical CT of the entire lung without contrast material was performed using scanning parameters of slice thickness, 10 mm; pitch, 1; tube voltage, 120 kV; tube current, 200 mA; and 0.75 sec per slice. Images focused on tumors and associated pneumonitis were obtained by helical scanning with slice thickness, 2 mm; pitch, 1; tube voltage, 120 kV; tube current, 250 mA; and 0.75 sec per slice. High-resolution CT was reconstructed using a high-spatial-resolution algorithm. Of 100 total CT series, high-resolution CT scans were obtained concurrently in 61 studies. An average of 4.5 CT series per lesion were performed, including an average of 2.8 high-resolution CT series. The mean follow-up period after high-resolution CT was 17.6 months (range, 4.5–51.6 months). No patients received chemotherapy.

Interpretation of CT Findings
The time of appearance of ground-glass opacities or dense consolidations (with respect to completion of radiation therapy), location of appearance (center or periphery of the planned target volume), serial changes (changes in density, size, and location), and time of appearance of bronchiectasis were systematically recorded. CT images were independently interpreted by four diagnostic radiologists who were familiar with the clinical diagnosis and the development of lung tumors. CT characteristics were determined on the basis of a consensus among at least three of the four examiners.


Results
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Abstract
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Subjects and Methods
Results
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References
 
Demographic characteristics of the lesions and characteristics of the radiation injuries are detailed in Table 1.

After hypofractionated stereotactic radiotherapy, ground-glass opacities and dense consolidations were observed as initial lung CT findings at 3–4 months. Thereafter, the ground-glass opacities either disappeared or evolved into dense consolidations. Dense consolidations that were seen initially gradually shrank to become solid or linear opacities consistent with lesion fixation (Figs. 1A, 1B, 1C, 1D, 1E, 1F, 2A, 2B, 2C, 2D, 2E, 2F, 3A, 3B, 3C, 3D, 3E, 3F). No ground-glass opacities or dense consolidations were observed at sites remote from the planned target volume.



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Fig. 1B. 59-year-old man with lung metastasis from rectal carcinoma. Typical characteristics of radiation pneumonitis and fibrosis after hypofractionated stereotactic radiotherapy are seen on serial lung CT scans after irradiation. CT scan at 1 month after irradiation shows decrease in tumor size.

 


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Fig. 1C. 59-year-old man with lung metastasis from rectal carcinoma. Typical characteristics of radiation pneumonitis and fibrosis after hypofractionated stereotactic radiotherapy are seen on serial lung CT scans after irradiation. CT scan at 4 months reveals appearance of dense consolidation and its surrounding ground-glass opacity.

 


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Fig. 1D. 59-year-old man with lung metastasis from rectal carcinoma. Typical characteristics of radiation pneumonitis and fibrosis after hypofractionated stereotactic radiotherapy are seen on serial lung CT scans after irradiation. CT scan at 8 months shows shrinkage of dense consolidation and its movement toward hilum.

 


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Fig. 1E. 59-year-old man with lung metastasis from rectal carcinoma. Typical characteristics of radiation pneumonitis and fibrosis after hypofractionated stereotactic radiotherapy are seen on serial lung CT scans after irradiation. CT scan at 11 months shows presence of dilated bronchi within opacity.

 


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Fig. 1F. 59-year-old man with lung metastasis from rectal carcinoma. Typical characteristics of radiation pneumonitis and fibrosis after hypofractionated stereotactic radiotherapy are seen on serial lung CT scans after irradiation. CT scan at 22 months shows fixation of opacity. Subsequent CT characteristics remained unchanged.

 


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Fig. 2B. 85-year-old man with squamous cell cancer. CT scan at 1 month after irradiation shows almost no change.

 


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Fig. 2C. 85-year-old man with squamous cell cancer. CT scan at 4 months shows presence of ground-glass opacity distributed in planned target volume.

 


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Fig. 2D. 85-year-old man with squamous cell cancer. CT scan at 6 months shows conversion of ground-glass opacity to dense consolidation and shift toward hilum. Tumor has almost disappeared.

 


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Fig. 2E. 85-year-old man with squamous cell cancer. CT scan at 10 months shows shrinkage of opacity and further movement toward hilum.

 


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Fig. 2F. 85-year-old man with squamous cell cancer. CT scan at 12 months shows further decrease in size. Subsequently, opacity remained unchanged.

 


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Fig. 3B. 70-year-old man with lung metastasis of oropharyngeal carcinoma. CT scan at 1 month after irradiation shows decrease in tumor size.

 


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Fig. 3C. 70-year-old man with lung metastasis of oropharyngeal carcinoma. CT scan at 3 months reveals appearance of dense consolidation in subpleural space of planned target volume.

 


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Fig. 3D. 70-year-old man with lung metastasis of oropharyngeal carcinoma. CT scan at 6 months shows increase in size of dense consolidation and onset of movement. Center of tumor is now located more cranially.

 


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Fig. 3E. 70-year-old man with lung metastasis of oropharyngeal carcinoma. CT scan at 9 months shows decrease in tumor size, thinning of dense consolidation, and movement of lesion toward hilum.

 


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Fig. 3F. 70-year-old man with lung metastasis of oropharyngeal carcinoma. CT scan at 12 months shows presence of linear opacity surrounding tumor and fixation of lesion.

 

Ground-glass opacities appeared on CT scans in four (18%) of 22 lesions at 3–6 months after completion of radiation therapy. They all corresponded closely to the planned target volume. In two instances, the ground-glass opacities were evenly distributed in the planned target volume (Figs. 1C and 3C), and in the other two instances the opacities remained unevenly distributed at 4 months, thereafter evolving into dense consolidations consistent with the planned target volume.

Dense consolidations appeared in 16 (73%) of 22 lesions on CT scans obtained at 3- to 8-months' follow-up. Of these, seven exhibited dense peritumoral consolidations corresponding to the planned target volume (Figs. 1C and 2D), and the remaining nine showed consolidation limited to the margin of the planned target volume, a short distance from the isocenter (Figs. 3C and 3D). Although dense consolidations shrank in seven (44%) of these 16 lesions, the consolidations did not disappear completely but persisted as solid or linear opacities (Figs. 1F, 2E, and 3F). This shrinkage occurred within 6–11 months after radiotherapy. In six of 10 lesions followed up for at least 12 months, the pulmonary opacities became fixed on CT scans, consistent with the development of fibrosis. Movement of the opacity was observed in six (37.5%) of the 16 densely consolidated lesions. This movement was detected simultaneously with shrinkage in five of the six lesions, with movement toward the hilum in five (Figs. 1A, 1B, 1C, 1D, 1E, 1F and 2A, 2B, 2C, 2D), and with movement away from the hilum in one.

Bronchiectasis was present in 10 (45.5%) of 22 lesions and developed almost contemporaneously with dense consolidations that contained dilated or thickened bronchi. Bronchial thickening and lumen irregularities caused by traction (i.e., traction bronchiectasis) became apparent along with movement of the opacities (Figs. 2D and 3E).


Discussion
Top
Abstract
Introduction
Subjects and Methods
Results
Discussion
References
 
Hypofractionated stereotactic radiotherapy, a new treatment method for small lung malignancies, differs considerably from conventional coplanar radiation therapy because it consists of delivering a single high dose of radiation with hypofractionation to small irradiation fields. Although hypofractionated stereotactic radiotherapy is expected to be highly effective in the control of localized lesions, its acceptance and indications will expand only if its use is not complicated by high rates of adverse reactions. Therefore, before considering increased radiation doses in the hope of achieving improved local therapeutic effects, a thorough clinical and radiologic evaluation of pulmonary parenchymal injuries caused by irradiation is needed to verify that hypofractionated stereotactic radiotherapy is a safe and effective treatment for small lung malignancies.

Classic radiation pneumonitis induced by conventional radiation therapy is characterized by a linear margin demarcating the treatment port and is uncommon with exposures of less than 30 Gy but inevitable for exposures greater than 40 Gy [8]. However, the reported incidence of clinical manifestations associated with radiation pneumonitis is 7–8%, and the symptoms are usually mild, despite imaging findings that may appear more prominent [9, 10]. In our study, only three patients reported a mild cough associated with radiation injury, and all were successfully treated with simple therapy. In contrast, sporadic radiation pneumonitis is an immune-mediated process resulting in lymphocytic alveolitis that leads to a response remote from the localized pulmonary irradiation and that is usually associated with severe symptoms and high mortality in the absence of a "threshold" dose [11]. Classic radiation pneumonitis can be classified as either early (1–3 months after irradiation) or late (3–6 months after irradiation), depending on the time of appearance of the pulmonary reaction to the radiation. In our study, hypofractionated stereotactic radiotherapy-induced lung injuries did not systematically develop in the center of treated volumes, but often began at the periphery. However, injuries eventually conformed to and remained in the planned target volume. These findings suggested that a threshold dose was required to develop pneumonitis, and that hypofractionated stereotactic radiotherapy-induced lung injuries were classifiable as classic radiation pneumonitis.

Evolution from ground-glass opacity to dense consolidation to fibrosis was observed on CT in a relatively small subset of our patients. In contrast, in a study of 3D conformal radiation therapy, Koenig et al. [12] observed the development of ground-glass opacity around tumors on CT scans at 3 months after radiation therapy in 19 of 19 patients treated with total doses between 69.6 and 90.3 Gy in 33–58 fractions. Three-dimensional conformal radiation therapy used in that study differs considerably from the hypofractionated stereotactic radiotherapy used in our study, particularly from the standpoint of the single dose. The incidence and severity of radiation pneumonitis can depend on the extent of irradiation, the total dose, and the number of fractions, and may also be influenced by concurrent chemotherapy [9]. Thus, the differences between the two studies with regard to CT patterns are probably attributable to researchers for the previous study using a higher radiation dose delivered as a single fraction. Therefore, we hypothesize that on CT, early or mild radiation injuries appear as ground-glass opacities, whereas severe radiation injuries appear as dense consolidations.

Movement of dense consolidations often occurred. Movement toward the hilum was seen in all but one case. Because shrinkage of the opacity and traction bronchiectasis were usually seen concurrently, the mechanism of these phenomena seems attributable to fibrosis. Therefore, we think that the apparent movement of the opacity is largely attributable to the deformity of the lung caused by fibrosis. Takahashi et al. [13] observed that the ground-glass opacities corresponded to thickened interlobular walls because of fibroblastic cells and collagen fibers in a pig model of radiation pneumonitis.

Takahashi et al. [13] also found that the ground-glass opacities were not evenly distributed but at pathology were predominant near the interstitium. In a dog model, the same radiation dose caused a more severe reaction when delivered to the periphery of the right lower lobe than to the right hilum [14]. These findings indicate that variable local sensitivity to radiation, depending on the amount of interstitium, causes nonuniform distribution of ground-glass opacities and dense consolidations.

We acknowledge several limitations in our study. Although we differentiated radiation injury patterns as ground-glass opacity, dense consolidation, and fibrosis, we had no pathologic proof. As with other studies examining radiation pneumonitis, we found it difficult to obtain specimens from otherwise asymptomatic patients. Another limitation was the relatively small number of patients in our study. Although it is fortunate that only a few patients complained of mild cough and recovered without resorting to steroids or hospital admission, the number of patients was too small to allow analysis of the relationship among symptomatic pneumonitis, patient background factors, and radiation treatment.

In assessing radiologic findings, residual tumor regrowth, lymphatic spread, and infection should be differentiated from radiation pneumonitis. Local recurrences especially are sometimes difficult to diagnose in the early phase because they are often asymptomatic, as is radiation pneumonitis. Four cases recurred after hypofractionated stereotactic radiotherapy, of which two had no radiation pneumonitis–induced opacities and one had minimal ground-glass opacity. In these three cases, the initial radiation effect was minimal or could not be evaluated and tumors gradually enlarged without a dramatic change in shape. Therefore, regrowth of the tumors was readily diagnosed. In the last case, the tumor had almost disappeared shortly after hypofractionated stereotactic radiotherapy. Dense consolidation surrounding the initial tumor appeared 6 months later, followed by overtly solid tumor on its periphery. Needle biopsy confirmed the presence of adenocarcinoma. We suppose that this may be a typical case of recurrence after hypofractionated stereotactic radiotherapy. However, we have experienced too few cases to draw a clear-cut distinction between recurrence and radiation pneumonitis. It is important to be especially careful during the early assessment of radiation pneumonitis on CT because the CT pattern evolves serially, and pulmonary opacity can move. We should be aware that the CT appearance reflects only one phase of the spectrum.

In conclusion, a size decrease in small lung tumors was generally observable on CT scans 1–3 months after completion of irradiation by hypofractionated stereotactic radiotherapy. This decrease in tumor size was accompanied by reduced areas of dense consolidation and surrounding ground-glass opacity at 3–6 months. Although ground-glass opacities generally resolved, the dense consolidations assumed typical CT patterns, including movement toward the hilum, shrinkage, and fixation at approximately 1 year after treatment. The incidence of ground-glass opacities was relatively low, and neither ground-glass opacities nor dense consolidations coincided exactly with dose distribution, occasionally developing away from the isocenter or remaining heterogeneous. Dynamic changes in ground-glass opacities and dense consolidations were observed over time. Our results indicate that assessment of lesions should be done with knowledge of these changes of radiation pneumonitis on CT during the first year after treatment, before fixation, to avoid misunderstandings about CT findings resembling tumor regrowth or the appearance of new lesions.


References
Top
Abstract
Introduction
Subjects and Methods
Results
Discussion
References
 

  1. Sibley GS. Radiotherapy for patients with medically inoperable stage I nonsmall cell lung carcinoma: smaller volumes and higher doses—a review. Cancer1998; 82:433 –438[Medline]
  2. Wasserman TH, Rich KM, Drzymala RE, Simpson JR. Stereotactic irradiation. In: Perez CA, Brady LW, eds. Principles and practice of radiation oncology, 3rd ed. Philadelphia, PA: Lippincott-Raven, 1998:387 –404
  3. Fukumoto S, Shirato H, Shimizu S, et al. Small-volume image-guided radiotherapy using hypofractionated, coplanar, and noncoplanar multiple fields for patients with inoperable stage I non-small cell lung carcinomas. Cancer 2002;95:1546 –1553[Medline]
  4. Uematsu M, Shioda A, Tahara K, et al. Focal, high dose, and fractionated modified stereotactic radiation therapy for lung carcinoma patients: a preliminary experience. Cancer1998; 82:1062 –1070.[Medline]
  5. Nagata Y, Negoro Y, Aoki T, et al. Clinical outcomes of 3D conformal hypofractionated single high-dose radiotherapy for one or two lung tumors using a stereotactic body frame. Int J Radiat Oncol Biol Phys 2002;52:1041 –1046[Medline]
  6. Libshitz HI, Shuman LS. Radiation-induced pulmonary change: CT findings. J Comput Assist Tomogr1984; 8:15 –19[Medline]
  7. Forrest LJ, Mahler PA, Vail DM, Mackie TR, Ladd WM, Kinsella TJ. Computed tomographic evaluation of radiation pneumonitis in a canine model. Radiat Oncol Investig1998; 6:128 –134[Medline]
  8. Libshitz HI, Southard ME. Complications of radiation therapy: the thorax. Semin Roentgenol1974; 9:41 –49[Medline]
  9. Movsas B, Raffin TA, Epstein AH, Link CJ Jr. Pulmonary radiation injury. Chest1997; 111:1061 –1076[Free Full Text]
  10. Roach M III, Gandara DR, Yuo HS, et al. Radiation pneumonitis following combined modality therapy for lung cancer: analysis of prognostic factors. J Clin Oncol1995; 13:2606 –2612[Abstract]
  11. Morgan GW, Breit SN. Radiation and the lung: a reevaluation of the mechanisms mediating pulmonary injury. Int J Radiat Oncol Biol Phys 1995;31:361 –369[Medline]
  12. Koenig TR, Munden RF, Erasmus JJ, et al. Radiation injury of the lung after three-dimensional conformal radiation therapy. AJR 2002;178:1383 –1388[Abstract/Free Full Text]
  13. Takahashi M, Balazs G, Pipman Y, et al. Radiation-induced lung injury using a pig model: evaluation by high-resolution computed tomography. Invest Radiol1995; 30:79 –86[Medline]
  14. Stenton CG, Boland J. Experimental radiation pneumonitis: radiographic and pathologic correlation. Cancer1967; 20:2170 –2183[Medline]

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