Value of Radiotherapy in Superior Vena Cava Syndrome P. P. Kumar, MD Washington, D.C.
The superior vena cava syndrome is among the most important radiotherapeutic emergencies currently known. It is almost always due to malignant disease and therefore no time should be wasted in establishing the histological diagnosis of the malignant tumor which causes the superior vena cava obstruction. The conventional slow, low-dose irradiation is a safe method of treatment. High-dose irradiation in this condition might further compromise the respiratory distress already present thus leading to sudden death. Superior vena cava syndrome, spinal cord compression, and vaginal bleeding secondary to malignancy are all radiotherapeutic emergencies. However, among these three, superior vena cava obstruction is a true radiotherapeutic emergency because cord compression and vaginal bleeding can be treated by other methods. Superior vena cava obstruction is nearly always caused by malignant disease. Lockich' reported that 97 percent of such cases are due to malignant disease, 75 percent due to bronchogenic cancer, 15 percent to lymphoma, and 7 percent to metastatic cancer. The remaining 3 percent were due to benign conditions such as thyroid goiter, mediastinal fibrosis, tuberculosis, and aortic aneurysm. Before the advent of penicillin, 40 percent of the superior vena cava syndromes resulted from syphilitic aneurysms. Roswitt2 showed that the vulnerability of the superior vena cava is related to the thinness of the vessel wall and its low venous pressure. The superior vena cava is also locked tightly into a compartment Requests for reprints should be addressed to Dr. P. P. Kumar, Department of Radiotherapy, Howard University Hospital, 2041 Georgia Avenue, NW, Washington, D.C. 20060.
of the right anterior superior mediastinum and is in intimate proximity to the right main stem bronchus. It is completely encircled by chains of lymph nodes, which drain all the structures of the right thoracic cavity and the lower part of the left. The superior vena cava syndrome was first described by William Hunter in 1757 and is characterized by obstruction in the superior mediastinum of the venous drainage of the upper thorax and neck. Signs of superior vena cava syndrome are edema and plethora of the neck and face, dilatation of collateral veins of the chest wall and neck, and usually respiratory distress. There may also be edema of the conjunctiva, with proptosis and central nervous system effects, such as headaches, visual disturbances, and disturbed states of consciousness. )
Materials and Methods Two cases of superior vena cava syndrome in patients who received two different schedules of radiotherapy are presented. In both the patients, the diagnosis was made on clinical and radiological bases and no attempt was made to obtain histological diagnoses.
JOURNAL OF THE NATIONAL MEDICAL ASSOCIATION, VOL. 70, NO. 2, 1978
Case 1 This 67-year-old black male, a chronic smoker, was seen in our clinic with a two-week history of progressive swelling of the neck and face (Figure 1). Physical examination revealed that the patient was in marked respiratory distress. There was marked edema of the face, neck, upper extremities, and upper thorax. There was also edema and ecchymosis of the conjunctiva. Dilated veins were seen over the upper anterior chest wall. X-ray of the chest showed a large radio-opaque shadow in the right hilar and paratracheal regions. The patient was started on external irradiation to the mediastinal area using conventional fractionation. After the initiation of external irradiation, the signs and symptoms did not progress further. There was gradual relief of symptoms and regression of edema. After a 4.500 rad midline tumor dose, there was complete regression of edema and the patient was fully asymptomatic (Figure 2). The patient died after six months but not from the superior vena cava syndrome.
Case 2 This 67-year-old black male, also a chronic smoker, was seen in our clinic with a two-month historv of swelling of the face and neck (Figure 3). Physical examination revealed that the patient was in no respiratory distress. There was diffuse edema of the face and neck. There was no edema of the upper extremities and upper thorax. The conjunctiva were normal. There were distended veins ever the neck and the 111
Figure 1. Pre-irradiation picture (Case 1) showing marked edema of the head and neck, upper extremities, and upper thorax.
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Figure 2. Post-low-dose irradiation picture (Case 1).
right arm. X-ray of the chest showed a large radio-opaque shadow in the right hilar region. The patient was started on high dose, twice a week, external irradiation. After receiving 2,000 rad in four fractions over 12 days, edema of the head and neck markedly increased and extended to the upper extremities and upper thorax (Figure 4). The patient became extremely dyspneic and expired.
Discussion Since 97 percent of the superior vena cava syndromes are due to malignant disease, radiotherapy can be initiated justifiably before establishing a histological diagnosis. Lockich1 vehe112
Figure 3. Pre-irradiation picture (Case 2) showing moderate edema of the head and neck region.
mently protests that "pitfalls" in management of the superior vena cava syndrome are related to the overzealous efforts to establish the site of obstruction and determine a specific histopathologic diagnosis. Rubin and Green4 have published clinical and experimental evidence that rapid highdose schedules of radiation therapy are not only well tolerated but are capable of quickly reversing the signs and symptoms of this syndrome. David Davenport et al) reported that an initial high-dose course of irradiation followed by conventional daily fractionation is as effective as slow low-dose schedules. In their series, 81 percent of lung cancers which produced superior vena cava syndrome were poorly differentiated carcinomas of which 46 percent were oat cell carcinomas. It is well known that any poorly differentiated carcinoma and oat cell carcinomas of the lung are highly radiosensitive. When high doses of irradiation are given for this histological type of tumor, the high degree of its response overcomes the initial radiation edema that would further compromise the respiratory reserve in these patients. However, in other histological types of lung cancer, which do not show high radiosensitivity such as oat cell and undifferentiated carcinomas, the initial radiation edema from high doses of irradiation does further com-
Figure 4. Post-high-dose irradiation picture (Case 2) showing increased edema of the head and neck region. The patient had marked respiratory distress. promise the respiratory reserve and might lead to sudden death. Since many patients with superior vena cava syndrome do not have a histological diagnosis, it is safe to treat them with conventional daily fractionation. If the tumor is undifferentiated, it responds well even to conventional doses and if it is well differentiated, the conventional radiation schedule does not produce radiation edema which might offset the slow response. Some have thought that nitrogen mustard would give an additional response to radiation therapy, but in a randomized study, Levitt6 found no advantage in using nitrogen mustard in conjunction with radiation therapy. Diuretic therapy has proven to be the best adjunct to radiation therapy in the superior vena cava syndrome. Literature Cited 1. Lokich JJ, Goodman R: Superior vena cava syndrome. JAMA 231:58-61, 1975 2. Roswitt B, Kaplan G, Jacobson HG: The superior vena cava obstruction in bronchogenic carcionma. Radiology 61:722-737, 1953 3. Urschel HC, Paulson DL: Superior vena caval canal obstruction. Dis Chest 49:155-164, 1966 4. Rubin P, Green J, Holzwasser G, et al: Superior vena caval syndrome: Slow low dose versus rapid high dose schedules. Radiology 81 :388-401, 1963 5. Davenport D, Ferree C, Blake D, et al: Response of superior vena cava syndrome to radiation therapy. Cancer 38:1577-1580, 1976 6. Levitt SH, Jones TK, Kilpatrick SJ, et al: Treatment of malignant superior vena caval obstruction. Cancer 24:447-451, 1969 7. Green J, Rubin P, Holzwasser G: The experimental production of superior vena caval obstruction. Radiology 81 :406-414, 1963
JOURNAL OF THE NATIONAL MEDICAL ASSOCIATION, VOL. 70, NO. 2, 1978
The superior vena cava syndrome is among the most important radiotherapeutic emergencies currently known. It is almost always due to malignant disease and therefore no time should be wasted in establishing the histological diagnosis of the malignant tumor which causes the superior vena cava obstruction. The conventional slow, low-dose irradiation is a safe method of treatment. High-dose irradiation in this condition might further compromise the respiratory distress already present thus leading to sudden death. Superior vena cava syndrome, spinal cord compression, and vaginal bleeding secondary to malignancy are all radiotherapeutic emergencies. However, among these three, superior vena cava obstruction is a true radiotherapeutic emergency because cord compression and vaginal bleeding can be treated by other methods. Superior vena cava obstruction is nearly always caused by malignant disease. Lockich' reported that 97 percent of such cases are due to malignant disease, 75 percent due to bronchogenic cancer, 15 percent to lymphoma, and 7 percent to metastatic cancer. The remaining 3 percent were due to benign conditions such as thyroid goiter, mediastinal fibrosis, tuberculosis, and aortic aneurysm. Before the advent of penicillin, 40 percent of the superior vena cava syndromes resulted from syphilitic aneurysms. Roswitt2 showed that the vulnerability of the superior vena cava is related to the thinness of the vessel wall and its low venous pressure. The superior vena cava is also locked tightly into a compartment Requests for reprints should be addressed to Dr. P. P. Kumar, Department of Radiotherapy, Howard University Hospital, 2041 Georgia Avenue, NW, Washington, D.C. 20060.
of the right anterior superior mediastinum and is in intimate proximity to the right main stem bronchus. It is completely encircled by chains of lymph nodes, which drain all the structures of the right thoracic cavity and the lower part of the left. The superior vena cava syndrome was first described by William Hunter in 1757 and is characterized by obstruction in the superior mediastinum of the venous drainage of the upper thorax and neck. Signs of superior vena cava syndrome are edema and plethora of the neck and face, dilatation of collateral veins of the chest wall and neck, and usually respiratory distress. There may also be edema of the conjunctiva, with proptosis and central nervous system effects, such as headaches, visual disturbances, and disturbed states of consciousness. )
Materials and Methods Two cases of superior vena cava syndrome in patients who received two different schedules of radiotherapy are presented. In both the patients, the diagnosis was made on clinical and radiological bases and no attempt was made to obtain histological diagnoses.
JOURNAL OF THE NATIONAL MEDICAL ASSOCIATION, VOL. 70, NO. 2, 1978
Case 1 This 67-year-old black male, a chronic smoker, was seen in our clinic with a two-week history of progressive swelling of the neck and face (Figure 1). Physical examination revealed that the patient was in marked respiratory distress. There was marked edema of the face, neck, upper extremities, and upper thorax. There was also edema and ecchymosis of the conjunctiva. Dilated veins were seen over the upper anterior chest wall. X-ray of the chest showed a large radio-opaque shadow in the right hilar and paratracheal regions. The patient was started on external irradiation to the mediastinal area using conventional fractionation. After the initiation of external irradiation, the signs and symptoms did not progress further. There was gradual relief of symptoms and regression of edema. After a 4.500 rad midline tumor dose, there was complete regression of edema and the patient was fully asymptomatic (Figure 2). The patient died after six months but not from the superior vena cava syndrome.
Case 2 This 67-year-old black male, also a chronic smoker, was seen in our clinic with a two-month historv of swelling of the face and neck (Figure 3). Physical examination revealed that the patient was in no respiratory distress. There was diffuse edema of the face and neck. There was no edema of the upper extremities and upper thorax. The conjunctiva were normal. There were distended veins ever the neck and the 111
Figure 1. Pre-irradiation picture (Case 1) showing marked edema of the head and neck, upper extremities, and upper thorax.
.
>
4/
ww
Figure 2. Post-low-dose irradiation picture (Case 1).
right arm. X-ray of the chest showed a large radio-opaque shadow in the right hilar region. The patient was started on high dose, twice a week, external irradiation. After receiving 2,000 rad in four fractions over 12 days, edema of the head and neck markedly increased and extended to the upper extremities and upper thorax (Figure 4). The patient became extremely dyspneic and expired.
Discussion Since 97 percent of the superior vena cava syndromes are due to malignant disease, radiotherapy can be initiated justifiably before establishing a histological diagnosis. Lockich1 vehe112
Figure 3. Pre-irradiation picture (Case 2) showing moderate edema of the head and neck region.
mently protests that "pitfalls" in management of the superior vena cava syndrome are related to the overzealous efforts to establish the site of obstruction and determine a specific histopathologic diagnosis. Rubin and Green4 have published clinical and experimental evidence that rapid highdose schedules of radiation therapy are not only well tolerated but are capable of quickly reversing the signs and symptoms of this syndrome. David Davenport et al) reported that an initial high-dose course of irradiation followed by conventional daily fractionation is as effective as slow low-dose schedules. In their series, 81 percent of lung cancers which produced superior vena cava syndrome were poorly differentiated carcinomas of which 46 percent were oat cell carcinomas. It is well known that any poorly differentiated carcinoma and oat cell carcinomas of the lung are highly radiosensitive. When high doses of irradiation are given for this histological type of tumor, the high degree of its response overcomes the initial radiation edema that would further compromise the respiratory reserve in these patients. However, in other histological types of lung cancer, which do not show high radiosensitivity such as oat cell and undifferentiated carcinomas, the initial radiation edema from high doses of irradiation does further com-
Figure 4. Post-high-dose irradiation picture (Case 2) showing increased edema of the head and neck region. The patient had marked respiratory distress. promise the respiratory reserve and might lead to sudden death. Since many patients with superior vena cava syndrome do not have a histological diagnosis, it is safe to treat them with conventional daily fractionation. If the tumor is undifferentiated, it responds well even to conventional doses and if it is well differentiated, the conventional radiation schedule does not produce radiation edema which might offset the slow response. Some have thought that nitrogen mustard would give an additional response to radiation therapy, but in a randomized study, Levitt6 found no advantage in using nitrogen mustard in conjunction with radiation therapy. Diuretic therapy has proven to be the best adjunct to radiation therapy in the superior vena cava syndrome. Literature Cited 1. Lokich JJ, Goodman R: Superior vena cava syndrome. JAMA 231:58-61, 1975 2. Roswitt B, Kaplan G, Jacobson HG: The superior vena cava obstruction in bronchogenic carcionma. Radiology 61:722-737, 1953 3. Urschel HC, Paulson DL: Superior vena caval canal obstruction. Dis Chest 49:155-164, 1966 4. Rubin P, Green J, Holzwasser G, et al: Superior vena caval syndrome: Slow low dose versus rapid high dose schedules. Radiology 81 :388-401, 1963 5. Davenport D, Ferree C, Blake D, et al: Response of superior vena cava syndrome to radiation therapy. Cancer 38:1577-1580, 1976 6. Levitt SH, Jones TK, Kilpatrick SJ, et al: Treatment of malignant superior vena caval obstruction. Cancer 24:447-451, 1969 7. Green J, Rubin P, Holzwasser G: The experimental production of superior vena caval obstruction. Radiology 81 :406-414, 1963
JOURNAL OF THE NATIONAL MEDICAL ASSOCIATION, VOL. 70, NO. 2, 1978
