Correspondence
Surveillance Scanning of Children with Medulloblastoma
N Engl J Med 1994; 331:483August 18, 1994
- Article
To the Editor:
Torres et al. (March 31 issue)1 conclude that surveillance scanning of children with medulloblastoma has limited clinical value. Unfortunately, the surveillance program that they describe can hardly be considered aggressive, as evidenced by the fact that asymptomatic recurrences were detected in only 4 of the 23 patients who had recurrences. I question the adequacy of a program in which the frequency of scanning dropped from every three months to every six months after a year, just before the median time to recurrence was reached. Despite the small numbers of patients, the median survival in the patients with asymptomatic recurrences was 15 months longer than in those with symptomatic recurrences. The authors' attempt to explain away the statistically significant difference in survival after recurrence by “lead-time and length biases” is unsatisfactory, since all the patients were undergoing scanning at least every six months at the time that recurrences were detected. The authors concede that their conclusion regarding the futility of scanning may not be valid if the technique becomes more sensitive, an event that was already occurring during the course of their study, as gadolinium-enhanced scanning became available.
Is the pessimistic view regarding the inevitability of death from recurrent medulloblastoma justified? The ability to treat patients with recurrent medulloblastoma depends not only on the stage at the time of recurrence but also on the extent of initial postoperative treatment. Patients who have not had a response to initial treatment with less intensive regimens may not have the same grave prognosis as do those whose initial treatment was more intensive. In a recent study, the five-year survival among 54 patients with recurrent medulloblastoma after initial treatment with irradiation, with or without chemotherapy (predominantly regimens not containing platinum), was 27 percent2.
Advances in high-dose myeloablative therapies may increase the likelihood of successful treatment in patients with recurrent disease. In a preliminary analysis of a Children's Cancer Group study in which patients with recurrent medulloblastoma or primitive neuroectodermal tumors received therapy, the two-year event-free survival was 41 percent3. Furthermore, technological innovations in radiotherapy, including radiosurgery and brachytherapy, allow the delivery of potentially tumoricidal doses of irradiation even in patients who have had previous radiotherapy. The definitive use of these techniques will depend on aggressive surveillance regimens that may detect focal recurrences at a size that is amenable to detection by these techniques.
3 ReferencesKaren L. Lindsley, M.D.
University of Washington Medical Center, Seattle, WA 981951
Torres CF ,Rebsamen S ,Silber JH , et al. Surveillance scanning of children with medulloblastoma. N Engl J Med 1994;330:892-895
Full Text | Web of Science | Medline2
Wara WM, Le QT, Sneed PK, et al. Pattern of recurrence of medulloblastoma after low-dose craniospinal radiotherapy. Int J Radiat Oncol Biol Phys (in press).
3
Finlay J ,Garvin J ,Allen J , et al. High-dose chemotherapy with autologous marrow rescue in patients with recurrent medulloblastoma/primitive neuroectodermal tumors. Prog Proc Am Soc Clin Oncol 1994;13:176-176 abstract.
Author/Editor Response
The authors reply:
To the Editor: In our patients, surveillance scans were obtained every three months during chemotherapy and for one year after the completion of therapy. In the patients who received only radiation therapy, scans were obtained every 3 months for approximately 15 months after the diagnosis; in those who received chemotherapy and radiation therapy this schedule was maintained for nearly 2 years after the diagnosis. Thus, the schedule of scanning did encompass the median period of 13 to 15 months from diagnosis to the detection of a recurrence.
At this time, data on the cure of recurrent medulloblastoma are largely anecdotal. We look forward to publication of the studies by Finlay and Wara and their coworkers that report prolonged survival in some patients with recurrent tumor1,2. If these and other studies document long-term disease-free survival after recurrence, then it may be possible to determine whether or not detection by surveillance improves the chance of a favorable outcome. In examining this question, we still need to consider the lead-time and length biases that artifactually may make surveillance programs appear beneficial.
2 ReferencesBeverly J. Lange, M.D.
Peter Phillips, M.D.
Children's Hospital of Philadelphia, Philadelphia, PA 191041
Finlay J ,Garvin J ,Allen J , et al. High-dose chemotherapy with autologous marrow rescue in patients with recurrent medulloblastoma/primitive neuroectodermal tumors. Prog Proc Am Soc Clin Oncol 1994;13:176-176 abstract.2
Wara WM, Le QT, Sneed PK, et al. Pattern of recurrence of medulloblastoma after low-dose craniospinal radiotherapy. Int J Radiat Oncol Biol Phys (in press).
- Citing Articles (4)
Citing Articles
1
Orazio Schillaci, Luca Filippi, Carlo Manni, Riccardo Santoni. (2007) Single-Photon Emission Computed Tomography/Computed Tomography in Brain Tumors. Seminars in Nuclear Medicine 37:1, 34-47
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Ute Bartels, Manohar Shroff, Lillian Sung, Ugo Dag-Ellams, Normand Laperriere, James Rutka, Eric Bouffet. (2006) Role of spinal MRI in the follow-up of children treated for medulloblastoma. Cancer 107:6, 1340-1347
CrossRef3
Bilgehan Yal
?n, M
CrossRef4
Evanthia Galanis, Jan C. Buckner, Paul Novotny, Roscoe F. Morton, William L. McGinnis, Robert Dinapoli, Paula Schomberg, Judith R. O'Fallon. (2000) Efficacy of neuroradiological imaging, neurological examination, and symptom status in follow-up assessment of patients with high-grade gliomas. Journal of Neurosurgery 93:2, 201-207
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