- Email: [email protected]
Imaging Strategy in Young Patients with Malignancy
CASE REPORTS
This radiation dosage to the uterus is 16 times greater than the alternate slice CT examination. Further, multislice CT examination cannot be terminated once it is initiated. However, the conventional CT examination with alternate slice technique does allow the examination to be terminated promptly when the radiographer identified the foetus as illustrated in our two cases, hence, imparts less calculated radiation dose. The total risk of fatal childhood cancer after multislice CT examination (combining the additional and natural risk) is estimated to be 1:520 compared with 1:1100 with the conventional CT examination. Despite doubling in the chance of a fatal cancer using the multislice CT examination, according to NRPB [7] guidelines the advice would remain the same for both multislice and conventional CT examination, i.e. no justification for termination of pregnancy or invasive procedure. Highdose examinations such as multislice CT should be avoided where possible in these patients. Even with adherence to current U.K. guidelines, inadvertent irradiation of two pregnancies has occurred. Young women with ovarian failure after treatment for Hodgkin’s disease challenge existing guidelines and in the two cases reported, limitation of the dose was achieved only by the vigilance of an experienced supervising radiographer using an old-fashioned CT protocol. While such emotive cases are rare they support the case for replacement of CT with imaging techniques such as US or MRI in follow-up of young adults with potentially curable malignancies such as Hodgkin’s disease. Acknowledgements. We thank the two patients for permission to report their cases, our CT radiographers for their attention to examination detail and patient care, Sheila Boyes for assistance with manuscript preparation and Dr Bob Bury for helpful contributions.
REFERENCES 1 Kaplan HS. Hodgkin’s Disease, 2nd ed. Cambridge, MA: Harvard University Press 1980 p. 434–435, 474–475.
165
2 Chapman RM, Sutcliffe SB, Malpas JS. Cytotoxic-induced ovarian failure in women with Hodgkin’s disease: 1. Hormone function. JAMA 1979;242:1877–1881. 3 Horning SJ, Hoppe RT, Kaplan HS, Rosenberg SA. Female reproductive potential after treatment for Hodgkin’s disease. N Engl J Med 1981;304:1377–1382. 4 Schilsky RL, Sherins RJ, Hubbard SM, Wesley MN, Young RC, DeVita VT. Long-term follow-up of ovarian function in women treated with MOPP chemotherapy for Hodgkin’s disease. Am J Med 1981;71: 552– 556. 5 Naik KS, Spencer JA, Craven CM, MacLennan KA, Robinson PJ. Staging lymphoma with computed tomography: comparison of contiguous and alternate 10 mm slice techniques. Clin Radiol 1998; 53:523–527. 6 Ortin TT, Shostak CA, Donaldson SS. Gonadal status and reproductive function following treatment Hodgkin’s disease in childhood: the Stanford experience. Radiat Oncol Biol Phys 1990;19:873–880. 7 Sharp C, Shrimpton JA, Bury RF. Diagnostic Medical exposure: advice on exposure to ionising radiation during pregnancy. Joint Guidance from NRPB, College of Radiographers and Royal College of Radiologists 1998. 8 Daviaud J, Fournet D, Ballongue C, et al. Reliability and feasibility of pregnancy home-use tests: laboratory validation and diagnostic evaluation by 638 volunteers. Clin Chem 1993;39:53–59. 9 Rehani MM, Berry M. Radiation doses in CT: the increasing doses of radiation need to be controlled. BMJ 2000;320:593 –594. 10 Munker R, Stengel A, Stabler A, Hiller E, Brehm G. Diagnostic accuracy of ultrasound and computed tomography in staging of Hodgkin’s disease. Verification by laparotomy in 100 cases. Cancer 1995;76:1460–1466. 11 Skillings JR, Bramwell V, Nicholson RL, Prato FS, Wells G. A prospective study of magnetic resonance imaging in lymphoma staging. Cancer 1991;67:1838 –1843. 12 Nyman R, Forsgren G, Glimelius B. Long-term follow-up of residual mediastinal masses in treated Hodgkin’s disease using MR imaging. Acta Radiol 1996;37:323–326. 13 Devizzi L, Maffioli L, Bonfante V, et al. Comparison of gallium scan, computed tomography, and magnetic resonance in patients with mediastinal Hodgkin’s disease. Ann Oncol 1997;8(Suppl. 1):53–56. 14 Shellock FG, Kanal E. Policies, guidelines, recommendations for MR imaging safety and patient management. J Magn Reson Imaging 1991; 1:97–101.
doi:10.1053/crad.2003.1161, available online at www.sciencedirect.com
Commentary: Imaging Strategy in Young Patients with Malignancy P. RILEY, J. OLLIFF Department of Radiology, University Hospital Birmingham NHS Trust, Queen Elizabeth Hospital, Edgbaston, Birmingham B15 2TH, U.K.
Author for correspondence: J. Olliff, Department of Radiology, University Hospital Birmingham NHS Trust, Queen Elizabeth Hospital, Edgbaston, Birmingham, B15 2TH, U.K. Tel.: þ44-0121-627-2458/2461; Fax: þ 44-121-697-8290; E-mail: [email protected]
Malignant disease is increasingly amenable to treatment with chemotherapy and radiotherapy either alone or in combination. Imaging is a crucial part of the staging process of all malignancies, and is essential when assessing disease response
166
CLINICAL RADIOLOGY
after treatment. Patients with stage 1 disease or in clinical remission may also relapse several years later, therefore, follow-up studies are often required for reassurance, or if the patient develops clinical or biochemical indicators of disease. Some potentially curable neoplasms, for example, Hodgkin’s disease and testicular germ cell tumours, have a peak incidence in relatively young adults. At present CT is the technique of choice for staging solid tumours [1]. Unfortunately this involves a considerable radiation dose (chest CT typical effective dose < 8 mSv) [2]. Although the risk of developing radiation-induced malignancy is small (12.5/million population/mSv) compared with the absolute lifetime risk in the United Kingdom (2500/million), stochastic effects of successive radiation exposures are additive. In our institution patients diagnosed with stage 1 testicular teratoma undergo a “standard” of five surveillance scars over a 2 year period after the initial staging CT, and each examination includes thorax, abdomen and pelvis. Two CTs are performed after treatment in patients with stage 1 seminoma. Patients who have stage 1 lymphoma may undergo anything from no post-treatment CT to five examinations over a 5 year period. These numbers relate to patients who remain disease free, but in patients who relapse the number and frequency of examinations will almost certainly increase. With combined abdomen and pelvic examinations delivering effective doses of 10 mSv [2] the additive dose during the follow-up period is considerable. Similar risks apply to the unborn foetus, although the number of examinations to which a foetus may be exposed is likely to be minimal. The paper by Wah et al. [3] describes the diagnosis of pregnancy in two patients during CT and highlights the difficulties in excluding this possibility in patients with ovarian failure following chemotherapy. It also raises questions regarding optimal imaging strategy in a cohort of relatively young patients whether they are pregnant or not. Radiation doses for CT of the abdomen and pelvis have increased by 35% over a 10 year period [4]. As radiologists we have a duty to consider alternative techniques whilst ensuring that enough information is available to answer the clinical question. The authors propose the alternative slice technique as a method of dose reduction when performing CT. Unfortunately this will not be applicable to multislice CT, which is currently replacing most single slice machines. Dixon [5] suggests that the abdomen could be examined with ultrasound in certain circumstances but Munker et al. [6] have demonstrated reduced sensitivity for the detection of para-aortic and iliac lymph nodes compared with CT. Interestingly, ultrasound is more sensitive in detecting involvement of liver and spleen. This group concluded that the two techniques complement each other in the staging of Hodgkin’s disease. Dixon also discusses the use of magnetic resonance imaging (MRI) for examination of the abdomen and pelvis in testicular cancer. Similar
consideration could also be given to patients with lymphoma and the detection of retroperitoneal nodal disease. Skillings et al. [7] concluded that MRI was less specific than CT in staging lymphoma, although more sensitive. Since 1991 magnetic field strengths have increased and gastrointestinal contrast agents have been developed for use in MRI. Both these factors are likely to improve the performance of MRI in staging and follow-up examinations, but this work needs to be repeated before MRI can be recommended as the technique of choice in such patients. Although MRI is a scarce resource, the number of scanners continues to increase, thereby increasing availability of a test with great potential for reducing radiation dose and its associated hazards. In addition, MRI is suitable for the examination of the mediastinum but CT remains the technique of choice for the assessment of lung parenchyma in lymphoma. One would envisage increasing use of MRI for the staging of cancer provided that clinical studies confirm that its sensitivity and specificity are at least as good as CT, if not better. In some cases this will have to be combined with CT assessment of lung parenchyma. Finally clinical assessment must be remembered. In the two cases reported by Wah et al. both pregnancies could have been confirmed by a simple and widely available investigation such as ultrasound. One of the patients does not appear to have had any symptoms to suggest disease recurrence. Radiologists and clinicians must consider the clinical evidence thoroughly before exposing of patients to radiation.
REFERENCES 1 Rehani M, Berry M. Radiation doses in computed tomography. BMJ 2000;320:593 –594. 2 Royal College of Radiologists, Making the Best Use of a Department of Clinical Radiology: Guidelines for Doctors, 4th ed London: Royal College of Radiologists, 1998. 3 Wah TM, Craven CM, Spencer JA. Pregnancy after treatment for Hodgkin’s lymphoma: inadvertent diagnosis by CT. Clin Radiol 2003; 58:163–165. 4 Wall BF, Hart D. Revised radiation doses for typical X-ray examinations, report on a recent review of doses to patients from medical X-ray examinations in the U.K. by NRPB. Br J Radiol 1997;70:437 –439. 5 Dixon AK. Whole body computed tomography: recent developments. In: Grainger RG et al. edu. Diagnostic Radiology: A Textbook of Medical Imaging. Edinburgh: Churchill Livingstone, 1991. 6 Munker R, Stengel A, Stabler A, Hiller E, Brehm G. Diagnostic accuracy of ultrasound and computed tomography in staging of Hodgkin’s disease.Verification by laparotomy in 100 cases. Cancer 1995;76: 1460– 1466. 7 Shillings JR, Bramwell V, Nicholson RL, Prato FS, Wells GA. Prospective study of magnetic resonance imaging in lymphoma staging. Cancer 1991,67:1838–1843.
This radiation dosage to the uterus is 16 times greater than the alternate slice CT examination. Further, multislice CT examination cannot be terminated once it is initiated. However, the conventional CT examination with alternate slice technique does allow the examination to be terminated promptly when the radiographer identified the foetus as illustrated in our two cases, hence, imparts less calculated radiation dose. The total risk of fatal childhood cancer after multislice CT examination (combining the additional and natural risk) is estimated to be 1:520 compared with 1:1100 with the conventional CT examination. Despite doubling in the chance of a fatal cancer using the multislice CT examination, according to NRPB [7] guidelines the advice would remain the same for both multislice and conventional CT examination, i.e. no justification for termination of pregnancy or invasive procedure. Highdose examinations such as multislice CT should be avoided where possible in these patients. Even with adherence to current U.K. guidelines, inadvertent irradiation of two pregnancies has occurred. Young women with ovarian failure after treatment for Hodgkin’s disease challenge existing guidelines and in the two cases reported, limitation of the dose was achieved only by the vigilance of an experienced supervising radiographer using an old-fashioned CT protocol. While such emotive cases are rare they support the case for replacement of CT with imaging techniques such as US or MRI in follow-up of young adults with potentially curable malignancies such as Hodgkin’s disease. Acknowledgements. We thank the two patients for permission to report their cases, our CT radiographers for their attention to examination detail and patient care, Sheila Boyes for assistance with manuscript preparation and Dr Bob Bury for helpful contributions.
REFERENCES 1 Kaplan HS. Hodgkin’s Disease, 2nd ed. Cambridge, MA: Harvard University Press 1980 p. 434–435, 474–475.
165
2 Chapman RM, Sutcliffe SB, Malpas JS. Cytotoxic-induced ovarian failure in women with Hodgkin’s disease: 1. Hormone function. JAMA 1979;242:1877–1881. 3 Horning SJ, Hoppe RT, Kaplan HS, Rosenberg SA. Female reproductive potential after treatment for Hodgkin’s disease. N Engl J Med 1981;304:1377–1382. 4 Schilsky RL, Sherins RJ, Hubbard SM, Wesley MN, Young RC, DeVita VT. Long-term follow-up of ovarian function in women treated with MOPP chemotherapy for Hodgkin’s disease. Am J Med 1981;71: 552– 556. 5 Naik KS, Spencer JA, Craven CM, MacLennan KA, Robinson PJ. Staging lymphoma with computed tomography: comparison of contiguous and alternate 10 mm slice techniques. Clin Radiol 1998; 53:523–527. 6 Ortin TT, Shostak CA, Donaldson SS. Gonadal status and reproductive function following treatment Hodgkin’s disease in childhood: the Stanford experience. Radiat Oncol Biol Phys 1990;19:873–880. 7 Sharp C, Shrimpton JA, Bury RF. Diagnostic Medical exposure: advice on exposure to ionising radiation during pregnancy. Joint Guidance from NRPB, College of Radiographers and Royal College of Radiologists 1998. 8 Daviaud J, Fournet D, Ballongue C, et al. Reliability and feasibility of pregnancy home-use tests: laboratory validation and diagnostic evaluation by 638 volunteers. Clin Chem 1993;39:53–59. 9 Rehani MM, Berry M. Radiation doses in CT: the increasing doses of radiation need to be controlled. BMJ 2000;320:593 –594. 10 Munker R, Stengel A, Stabler A, Hiller E, Brehm G. Diagnostic accuracy of ultrasound and computed tomography in staging of Hodgkin’s disease. Verification by laparotomy in 100 cases. Cancer 1995;76:1460–1466. 11 Skillings JR, Bramwell V, Nicholson RL, Prato FS, Wells G. A prospective study of magnetic resonance imaging in lymphoma staging. Cancer 1991;67:1838 –1843. 12 Nyman R, Forsgren G, Glimelius B. Long-term follow-up of residual mediastinal masses in treated Hodgkin’s disease using MR imaging. Acta Radiol 1996;37:323–326. 13 Devizzi L, Maffioli L, Bonfante V, et al. Comparison of gallium scan, computed tomography, and magnetic resonance in patients with mediastinal Hodgkin’s disease. Ann Oncol 1997;8(Suppl. 1):53–56. 14 Shellock FG, Kanal E. Policies, guidelines, recommendations for MR imaging safety and patient management. J Magn Reson Imaging 1991; 1:97–101.
doi:10.1053/crad.2003.1161, available online at www.sciencedirect.com
Commentary: Imaging Strategy in Young Patients with Malignancy P. RILEY, J. OLLIFF Department of Radiology, University Hospital Birmingham NHS Trust, Queen Elizabeth Hospital, Edgbaston, Birmingham B15 2TH, U.K.
Author for correspondence: J. Olliff, Department of Radiology, University Hospital Birmingham NHS Trust, Queen Elizabeth Hospital, Edgbaston, Birmingham, B15 2TH, U.K. Tel.: þ44-0121-627-2458/2461; Fax: þ 44-121-697-8290; E-mail: [email protected]
Malignant disease is increasingly amenable to treatment with chemotherapy and radiotherapy either alone or in combination. Imaging is a crucial part of the staging process of all malignancies, and is essential when assessing disease response
166
CLINICAL RADIOLOGY
after treatment. Patients with stage 1 disease or in clinical remission may also relapse several years later, therefore, follow-up studies are often required for reassurance, or if the patient develops clinical or biochemical indicators of disease. Some potentially curable neoplasms, for example, Hodgkin’s disease and testicular germ cell tumours, have a peak incidence in relatively young adults. At present CT is the technique of choice for staging solid tumours [1]. Unfortunately this involves a considerable radiation dose (chest CT typical effective dose < 8 mSv) [2]. Although the risk of developing radiation-induced malignancy is small (12.5/million population/mSv) compared with the absolute lifetime risk in the United Kingdom (2500/million), stochastic effects of successive radiation exposures are additive. In our institution patients diagnosed with stage 1 testicular teratoma undergo a “standard” of five surveillance scars over a 2 year period after the initial staging CT, and each examination includes thorax, abdomen and pelvis. Two CTs are performed after treatment in patients with stage 1 seminoma. Patients who have stage 1 lymphoma may undergo anything from no post-treatment CT to five examinations over a 5 year period. These numbers relate to patients who remain disease free, but in patients who relapse the number and frequency of examinations will almost certainly increase. With combined abdomen and pelvic examinations delivering effective doses of 10 mSv [2] the additive dose during the follow-up period is considerable. Similar risks apply to the unborn foetus, although the number of examinations to which a foetus may be exposed is likely to be minimal. The paper by Wah et al. [3] describes the diagnosis of pregnancy in two patients during CT and highlights the difficulties in excluding this possibility in patients with ovarian failure following chemotherapy. It also raises questions regarding optimal imaging strategy in a cohort of relatively young patients whether they are pregnant or not. Radiation doses for CT of the abdomen and pelvis have increased by 35% over a 10 year period [4]. As radiologists we have a duty to consider alternative techniques whilst ensuring that enough information is available to answer the clinical question. The authors propose the alternative slice technique as a method of dose reduction when performing CT. Unfortunately this will not be applicable to multislice CT, which is currently replacing most single slice machines. Dixon [5] suggests that the abdomen could be examined with ultrasound in certain circumstances but Munker et al. [6] have demonstrated reduced sensitivity for the detection of para-aortic and iliac lymph nodes compared with CT. Interestingly, ultrasound is more sensitive in detecting involvement of liver and spleen. This group concluded that the two techniques complement each other in the staging of Hodgkin’s disease. Dixon also discusses the use of magnetic resonance imaging (MRI) for examination of the abdomen and pelvis in testicular cancer. Similar
consideration could also be given to patients with lymphoma and the detection of retroperitoneal nodal disease. Skillings et al. [7] concluded that MRI was less specific than CT in staging lymphoma, although more sensitive. Since 1991 magnetic field strengths have increased and gastrointestinal contrast agents have been developed for use in MRI. Both these factors are likely to improve the performance of MRI in staging and follow-up examinations, but this work needs to be repeated before MRI can be recommended as the technique of choice in such patients. Although MRI is a scarce resource, the number of scanners continues to increase, thereby increasing availability of a test with great potential for reducing radiation dose and its associated hazards. In addition, MRI is suitable for the examination of the mediastinum but CT remains the technique of choice for the assessment of lung parenchyma in lymphoma. One would envisage increasing use of MRI for the staging of cancer provided that clinical studies confirm that its sensitivity and specificity are at least as good as CT, if not better. In some cases this will have to be combined with CT assessment of lung parenchyma. Finally clinical assessment must be remembered. In the two cases reported by Wah et al. both pregnancies could have been confirmed by a simple and widely available investigation such as ultrasound. One of the patients does not appear to have had any symptoms to suggest disease recurrence. Radiologists and clinicians must consider the clinical evidence thoroughly before exposing of patients to radiation.
REFERENCES 1 Rehani M, Berry M. Radiation doses in computed tomography. BMJ 2000;320:593 –594. 2 Royal College of Radiologists, Making the Best Use of a Department of Clinical Radiology: Guidelines for Doctors, 4th ed London: Royal College of Radiologists, 1998. 3 Wah TM, Craven CM, Spencer JA. Pregnancy after treatment for Hodgkin’s lymphoma: inadvertent diagnosis by CT. Clin Radiol 2003; 58:163–165. 4 Wall BF, Hart D. Revised radiation doses for typical X-ray examinations, report on a recent review of doses to patients from medical X-ray examinations in the U.K. by NRPB. Br J Radiol 1997;70:437 –439. 5 Dixon AK. Whole body computed tomography: recent developments. In: Grainger RG et al. edu. Diagnostic Radiology: A Textbook of Medical Imaging. Edinburgh: Churchill Livingstone, 1991. 6 Munker R, Stengel A, Stabler A, Hiller E, Brehm G. Diagnostic accuracy of ultrasound and computed tomography in staging of Hodgkin’s disease.Verification by laparotomy in 100 cases. Cancer 1995;76: 1460– 1466. 7 Shillings JR, Bramwell V, Nicholson RL, Prato FS, Wells GA. Prospective study of magnetic resonance imaging in lymphoma staging. Cancer 1991,67:1838–1843.