Clinical Evaluation of Computed Tomography in Esophageal Cancer

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1 THE KURUME MEDICAL JOURNAL Vol.28, p.53-61, 1981 Clinical Evaluation of Computed Tomography in Esophageal Cancer MASAYUKI HAMADA, YUKIHIKO YASUDA, SHINICHI NAKAYAMA, SHIGERU KIKUCHI, HARUMI AKAGAWA, KIYOSHI YANO AND HISASHI OHTAKE Department of Radiology, Kurume University School of Medicine, Kurume, 830 and Department of Radiology, Yanagawa Public Hospital, Yanagawa, 832 Japan Received for publication January 28, 1981 Summary: Transverse spread of esophageal cancer is a significant prognostic factor equal to the influence of location and length on esophagogram. To examine extraluminal spread of tumors, we studied CT evaluation of the diagnosis and the treatment planning in esophageal cancer. In all 25 patients (100%), CT demonstrated a mass in the surrounding structures. In patients with cancer of the middle third of the esophagus displacement of trachea, aorta and left main bronchus were clearly detected by CT. There were also three patients with complications of esophagobronchial and esophagomediastinal fistulae after radiotherapy. In these cases, it was important to give palliative radiotherapy with decreased total dose. We believe that CT examination is a useful adjunct in the diagnosis of transverse extent of advanced esophageal cancer and for the treatment planning of irradiation in these cases. Key words: CT scan \ esophageal cancer \ lymph node metastasis \ mediastinal spread \ radiotherapy Introduction Materials and Methods Esophageal cancer is often well advanced and virtually all patients are symptomatic at the time of diagnosis. The treatment protocol for advanced carcinoma depends on several clinical conditions, including radiotherapy. Location and length of tumor on the esophagogram is a significant prognostic factor. Sometimes esophageal cancer spreads externally and invaded contiguous structures such as pericardium, trachea, aorta and pulmonary parenchyma. These extensions can be extremely lethal. For the diagnosis of extraluminal extension, we studied CT scans and analyzed them in terms of their influence upon radiotherapeutic planning. Between January, 1979, and September, 1980, 25 esophageal cancer patients and 35 scans were studied. CT scan was performed with TOSHIBA TCT-60 A Whole Body Scanner. Scan time was 3 seconds and the images were displayed on a 320 ~ 320 matrix. The scans were obtained with a slice thickness of 1.2 cm. Contrast agent was administrated intravenously and orraly to all patients. The diagnosis of esophageal cancer was established by clinical presentation and biopsy. All patients were given a course of radiotherapy with the basic treatment plan to deliver 6000 rads over a period of 8 weeks. In 10 cases, CT examination was carried out both before and after radiation treatment. 53

2 54 HAMADA, ET AL. Clinical details of the esophageal cancer are shown in Table 1. There were 17 males and 8 females. The age of the patients ranged from 45 to 80 years old, with a mean of 68 years old. Nineteen of the lesions were in the middle third and 6 were in the lower third of the esophagus. Tumor size measured by the length of the tumor on the esophagogram varied from 3 to 12 cm. CT examinations of esophageal cancer were reviewed for the following findings: 1) tumor formation (mass formation), 2) lymphadenopathy, and 3) displacement of surrounding structures such as trachea, bronchus and vascular system. Results Clinical findings of esophageal cancer are shown in Table 2. In all 25 patients, CT demonstrated the tumor formation. The size of mass shadow ranged from 1.9 to 5.0 cm. In the cases of middle third esophageal cancer, displacement of trachea, aorta and left main bronchus was clearly observed. There were 3 cases with complications such as esophagobronchial and esophagomediastinal fistulae after radiotherapy. For these cases, irradiation planning and observation of clinical course were most important during preliminary care. Metastatic lymphadenopathy was proven in 5 cases in which the previous diagnosis of metastasis had not been made by conventional study. Diagnostic value of the location of the lesion in patients with esophageal cancer according to the course of radiotherapy are shown in Table 3. Six of 10 cases were middle third esophageal cancer and 4 were lower third. In the middle third cases, admission CT clearly showed the displacement of trachea, bronchus and aorta by the tumor. radiation treatment, this displacement was not visible on CT. Compared to conventional film study, CT more clearly distinguishes the contour and the size of mass shadow from surrounding structures. TABLE 1 Clinical detail of 25 patients with esophageal cancer TABLE 2 CT finding of esophigeal cancer in admission study

3 COMPUTED TOMOGRAPHY IN ESOPHAGEAL CANCER 55 TABLE 3 Diagnostic value of the location of the lesion in patients with esophageal cancer according to the course of radiotherapy * Film study : Chest roentogenogram and esophagogram Case Report Case 1. ( 1 A, B) Y. A., 50 year old man with chief complaint of dysphagia. Esophagogram on admission showed tumor of spiral type measuring 5 cm in length. Vertical axis of esophagus was deviated to the right side due to fixation to the vertebrae. This finding suggested evidence of extraesophageal spread. radiotherapy treatment with 6000 rads, barium study showed esophageal stenosis in spite of improvement of symptoms, and esophageal deviation remained. Admission CT study showed mass shadow in the surrounding structures. Upper anterior structures, including trachea and vascular system, were pressed anteriorly by this tumor. radiotherapy, CT showed perforation into the mediastinum and pleural space accompanied with tumor regression. In this case, the tumor may be controlled by progressively decreasing the total doses. Case 2. ( 2 A, B) J. A., 73 year old man with chief complaint of dysphagia. Admission esophagogram showed tumor of spiral type, measuring 9 cm vertically in the middle third esophagus. Histologic examination indicated squamous cell carcinoma. radiotherapy treatment with 6000 rads, tumor showed marked regression on repeat esophagogram. Admission CT study revealed a ring mass shadow with thickened wall among thoracic aorta, vertebra and main bronchus. It measured 4.5 cm transversely. It also showed marked re-

4 56 HAMADA, ET AL. 1A. 1B. A. Esophagogram shows B. radiotherapy, On admission study, 1. Case cancer 1 Y. A. of funnel 50 year type old man in the middle third esophageal stenosis shows no improvement. retrotracheal mass is clearly detected, mediastinal component, including the trachea, radiotherapy, perforation into the right is displaced pleural space esophagus. the anterior anteriorly. was detected.

5 COMPUTED TOMOGRAPHY A. B. IN ESOPHAGEAL CANCER 2 A. 2 B. 2. Case 2 J. A. 73 year old man Esophagogram on admission shows advanced tumor of spiral type in the middle third esophagus. treatment with 6000 rads, the massive tumor has disappeared. At the level of tracheal bifurcation, ring mass shadow with thickened wall is visible. Transverse spread of tomor is 4cm in size. a dose of 6000 rads, primary tumor shows marked regression. 57

6 58 HAMADA, ET AL. 3A. 3B.

7 COMPUTED TOMOGRAPHY IN ESOPHAGEAL A. Esophagogram middle third 3. at the esophagus. B. in transverse image. radiotherapy CT C. on esophagogram. In the retrotracheal Case 3 time of space, node gression on tion therapy. repeat has markedly CT scan 64 year preirradiation radiotherapy tumor admission pathy which was not detected irradiated. Five months later, 59 3C. T. M. discloses CANCER old shows a mass shadow in the mass shadow appears smaller regression CT scan man similar suggestes to the small findings lymphadeno- on conventional study. This lesion was not repeat esophagogram shows that this lymph enlarged. after radia- Histological Case 3. ( 3 A, B, C) T. M., 64 year old man with chief complaint of retrosternal pain and dysphagia. Admission esophagogram revealed spiral type of tumor, 8 cm in length in the middle third region. finding was squamous cell with 6000 rads, re- carcinoma. radiotherapy peat esophagogram showed significant improvement. On CT scan, admission study revealed a mass shadow involving the thoracic aorta, left main bronchus and vertebra. radiotherapy the mass

8 60 HAMADA, ET AL. shadow clearly reduced in size. In addition to these findings, admission CT scan revealed a small mass shadow away from the primary tumor. This was a metastatic lesion to the lymph node not previously detected by conventional methods. This lesion was not irradiated. Three months later, esophagogram proved mass enlargement accompanied with displacement of trachea and esophagus ( 3 C). Discussion Conventional X-ray examination is effective both in diagnosing esophageal cancer and in offering prognostic considerrations. Esophagogram details the internal and vertical spread of the tumor. But this method cannot show the extent of direct spread into extra esophageal tissue and submucosal lymphatics. (Moss et al., 1973). It is important to evaluate not only intraluminal and vertical changes, but also extraluminal abnormalities, such as involvement of surrounding structures and invasion of the mediastinum. On chest radiogram and laminagram, cases of middle third or lower esophageal cancer are indicated by abnormality of azygoesophageal line and retrotracheal shadow (Daf f ner et al., 1978; Marvin et al., 1979). Pneumomediastinography, intraosseous, and retrograde azygography have been used for more detailed investigation of esophageal cancer (Berne, 1962; Carlyle et al., 1976; Makino, 1975). It is also generally agreed that computed tomography is useful in establishing the diagnosis of mediastinal abnormalities (Goldwin et al., 1977; Heitzman et al., 1977; Crowe et al., 1978). CT in diseases of the chest is indicated in the following situations : 1) evaluation of lesions partially or questionably hidden by the mediastinum, 2) evaluation of the tissue density of lesions by determination of their attenuation coef f i- cient. 3) evaluation of mediastinum that is abnormal or questionably abnormal on standard radiography and 4) evaluation of tumor extent or localization in the mediastinum. As anticipated in this study esophageal carcinoma was clearly observed as a mass shadow in surrounding structures. anaka et al. (1977) showed a well-circumscribed mass shadow contiguous to the left main bronchus and aortic knob on CT film. Nishimura et al. (1980) reported that a mass shadow of esophageal cancer was found in 91.7 o of cases. We evaluated CT scans for extraluminal extent to assist in surgical exploration treatment planning. In our admission series of CT scans we also noted that the lesions were of several shapes and sizes. CT is useful in determining the transverse extent of esophageal cancer which is otherwise difficult to circumscribe by conventional X-ray examination (Honi et al., 1978; Yonemoto et al., 1980). Treatment protocol of esophageal cancer should depend on not only the location and the length of tumor on esophagogram, but also on gross extent as determined by CT. A variety of irradiation methods may be used, depending on the clinical situation, including CT information : radical radiothrapy, combined radiotherapy and surgery and palliative treatment. Lymph node metastasis is found in approximately 70 o of patients at postmortem examination (Bloedorm and Kasdorf, 1971). Information regarding the distribution of lymph node metastasis is important in treatment planning. CT occasionally detects lymphadenopathy removed from the primary tumor. Lymphadenopathy which is difficult to diagnose with conventional examination methods, was found in 5 of our cases with CT. Case 3 was diagnosed with lymph node swelling on admission CT. But because the finding was within normal limits on conventional study, this lesion was not involved in the irradiation field. This case will benefit

9 COMPUTED TOMOGRAPHY IN ESOPHAGEAL CANCER 61 from irradiation along a more extended longitudinal field. In cases of severe compression of trachea, bronchus and aorta, a decreased irradiation regimen should be used in order to less the chances of complication of perforation and tumor hemorrhage. CT findings are very useful in making treatment decisions as to whether irradiation treatment should be continued. References BERNE, A. S. (1962). Diagnostic carbon dioxidal pneumomediastinography as an extension of scalene lymph node biopsy. New Eng. J. Med. 267, BLOEDORN, F. G. and KASDORF, H. (1971). Radiotherapy in squamous cell carcinoma of the esophagus. In Oncology 1970, Proceedings the Tenth International Cancer Congress, Chicago, Year Book Medical Publishers, CARLYLE, D. R., GOLDSTEIN, H. M., WALLACE, S., MEDELLIN, H. and VENTEMIGLIA, R. A. (1976). Azygography in the pretreatment evaluation of esophageal carcinoma. Brit. J. Radiol. 49, CROW, J. K., BROWN, L. R. and MUHM, J. R. (1978). Computed tomography of the mediastinum. Radiology, 128, DAFFNER, R. H., POSTLETHWAIT, R. W. and PUTMAN, C. E. (1978). Retrotracheal abnormalities in esophageal carcinoma, Prognostic implications. Am. J. Roentgenol. 130, GOLDWIN, R. L., HEITZMAN, E. R. and PROTO, A. V. (1977). Computed tomography of the mediastinum: normal anatomy and indications for the use of CT. Radiology, 124, HEITZMAN. E, R., GOLDWIN, R. L. and PROTO, A. V. (1977). Radiologic analysis of the mediastinum utilizing computed tomography. Am. J. Roentgenol. 128, HORI, S., MIYOSHI, K., OHKAWA, M., SONOYAMA, A., KA JITA, A., INOUE, T., NAKAII, A. and MATSUDA, H. (1978). CT evaluation of esophageal disease. Nipp. Act. Radiol. 38, MAKING, M. (1975). The clinical investigation of retrograde azygography in esophageal cancer. Nipp. Act. Radiol. 35, MARVIN, M. L., HILL, A. C. and LIESHITZ, I. H. (1979). Esophageal cancer radiographic chest findings and their prognostic significance. Am. J. Roentgenol. 133, MOSS, T. T., BRAND, N. W. and BATTIFORA, H. (1973). Radiation oncology., rationale, technique, results., 4 th edition, Mosby, 240. NISHIMURA, S., YOSHIDA, H., IMASHIRO, Y., MATSUO, M., DOI, S., MURATA, M., KAWANO, M. and KIMURA, S. (1980). CT evaluation of esophageal cancer. Jap. J. Gastroenterol. 77, 367. TANAKA, H., KURATA, M. and MUROMOTO, H. (1979). Evaluation of computed tomography in the mediastinal diseases. Jap. J. Clin. Radiol. 24, YONEMOTO, J., OHTAKE, Y., OKUAKI, Y., KIMURA, K. and MATSUKAWA, A. (1979). CT evaluation of tumorous spread in esophageal cancer. Nipp. Act. Radiol. 39, 899.