Correspondence

Brain Tumors

N Engl J Med 2001; 344:1478-1479May 10, 2001

Article

To the Editor:

DeAngelis, in her review article on brain tumors (Jan. 11 issue),1 emphasizes that “irradiation of the cranium, even at low doses, can increase the incidence of meningiomas by a factor of 10 and the incidence of glial tumors by a factor of 3 to 7.” The two articles cited to support this statement2,3 deal with children treated with radiation. The exposure of the brain in the patients with tinea capitis was 100 to 200 rad, and in the patients with acute leukemia, the brain was exposed to 2400 rad.

It is possible that the author meant exposure to low-dose radiation therapy. If that is the case, the statement should be clarified accordingly or, even better, quantified, to avoid misinterpretation with respect to the highly sensitive and controversial issue of radiation carcinogenesis at low doses of radiation.

Ernesto Lubin, M.D.
Tel Aviv University, Ramat Gan 52246, Israel

3 References

1. 1

   DeAngelis LM. Brain tumors. N Engl J Med 2001;344:114-123
   Full Text | Web of Science | Medline

2. 2

   Pollak L, Walach N, Gur R, Schiffer J. Meningiomas after radiotherapy for tinea capitis -- still no history. Tumori 1998;84:65-68
   Web of Science | Medline

3. 3

   Walter AW, Hancock ML, Pui CH, et al. Secondary brain tumors in children treated for acute lymphoblastic leukemia at St Jude Children's Research Hospital. J Clin Oncol 1998;16:3761-3767
   Web of Science | Medline

To the Editor:

DeAngelis states, “Ionizing radiation is the only unequivocal risk factor that has been identified for glial and meningeal neoplasms. Irradiation of the cranium, even at low doses, can increase the incidence of meningiomas by a factor of 10.” Since standard dental practice makes generous use of x-ray examinations and since a beam aimed at areas in the upper jaw would be likely to entail “low-dose” scattering to the cranium, should the criteria for the use of dental x-ray examinations be made more strict?

Philip R. Sullivan, M.D.
280 Washington St., Suite 202, Brighton, MA 02135

Author/Editor Response

Dr. DeAngelis replies:

To the Editor: Dr. Lubin correctly points out that only ionizing cranial radiotherapy has been shown to predispose people to the development of meningiomas and gliomas. However, it can do so after exposure to low doses, as documented in survivors of the atomic bomb at Hiroshima, who have had an increased incidence of meningiomas after exposure to 10 to 100 cGy.1 Other forms of radiation, such as the nonionizing radiation emitted by cellular telephones, do not lead to brain tumors.2

Dr. Sullivan raises an important question. The influence of dental x-ray examinations on the incidence of brain tumors has been studied. There are some studies that suggest a trend toward an increase in the risk of brain tumors with dental x-ray examinations, but the effect is not statistically significant.3 Furthermore, other data suggest that dental x-ray studies are protective against the development of brain tumors, and most investigators conclude that they do not predispose people to any type of intracranial tumor.4,5 Therefore, dental x-ray examinations are safe and do not lead to cerebral tumors.

Lisa M. DeAngelis, M.D.
Memorial Sloan-Kettering Cancer Center, New York, NY 10021

5 References

1. 1

   Shintani T, Hayakawa N, Hoshi M, et al. High incidence of meningioma among Hiroshima atomic bomb survivors. J Radiat Res (Tokyo) 1999;40:49-57
   CrossRef | Web of Science | Medline

2. 2

   Inskip PD, Tarone RE, Hatch EE, et al. Cellular-telephone use and brain tumors. N Engl J Med 2001;344:79-86
   Full Text | Web of Science | Medline

3. 3

   Preston-Martin S, Mack W, Henderson BE. Risk factors for gliomas and meningiomas in males in Los Angeles County. Cancer Res 1989;49:6137-6143
   Web of Science | Medline

4. 4

   Ryan P, Lee MW, North B, McMichael AJ. Amalgam fillings, diagnostic dental x-rays and tumours of the brain and meninges. Eur J Cancer B Oral Oncol 1992;28:91-95
   CrossRef

5. 5

   Maillie HD, Gilda JE. Radiation-induced cancer risk in radiographic cephalometry. Oral Surg Oral Med Oral Pathol 1993;75:631-637
   CrossRef | Medline

Citing Articles (1)

Citing Articles

1. 1

   Vincent Lubrano, Katia Prod’homme, Jean-François Démonet, Barbara Köpke. (2011) Language monitoring in multilingual patients undergoing awake craniotomy: A case study of a German–English–French trilingual patient with a WHO grade II glioma. Journal of Neurolinguistics
   CrossRef