One vs two or more brachytherapy applications in cervical cancer

One vs two or more brachytherapy applications in cervical cancer

Im J Rndmron Oncology timl Phw Vol. Pnnted in the U.S.A. All rights reserved. 20. pp. 0360-3016/91 $3.00 + .W Copyright 0 1991 Pergamon Press plc 1...

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Im J Rndmron Oncology timl Phw Vol. Pnnted in the U.S.A. All rights reserved.

20. pp.

0360-3016/91 $3.00 + .W Copyright 0 1991 Pergamon Press plc

179-180

e Correspondence

TO BOOST,

WHY

AND HOW

5. Regine, W. F.; Ayyangar, K. M.; Komarnicky, L. T.; Bhandare, N.; Mansfield, C. M. Computer-CT planning of the electron boost in definitive breast irradiation. Int. J. Radiat. Oncol. Biol. Phys. 20: 12 1- 125; 199 I.

To fhe Editor: Drs. Recht and Harris’ editorial concerning the “boost” dose in the conservative management of early stage breast cancer serves well in further bringing forth this issue and its surrounding controversies. At present, the rationale for use of a boost is obvious because it has been our experience and that of others that the majority of local failures following conservative therapy occur at the primary site (I, 2,4). As astutely pointed out by Drs. Recht and Harris, the NSABP B-06 trial did not make uniform use of tissue compensators and therefore cannot be used fairly in addressing the question of “To boost or not to boost?” It would therefore seem that the major argument against the use of a boost is invalid. This then leaves us with the issue as to “How to do it?’ We are essentially left with two options, interstitial implantation versus electron beam. Proper target volume localization cannot be more accurate than with use of “perioperative implantation” at the time of excisional lumpectomy (3). Perioperative implantation at the time of lumpectomy and axillary node dissection adds no additional expense in terms of hospitalization. The patient saves time and money because there is no need for 2 weeks of electron therapy. When implantation is not performed, tumor localization can most accurately be performed with proper placement of surgical clips and subsequent use of computer-CT planning (5). We believe that this technique, in addition to an accurate target volume, allows for significant sparing of normal tissue.

ONE VS TWO OR MORE BRACHYTHERAPY APPLICATIONS

IN CERVICAL

CANCER

To fhe Editor: Rotman and associates present a number of points in their editorial that merit further discussion. Although the classical European therapeutic techniques were developed empirically, they were the product of many years of careful clinical observation and modification. The Paris technique, though apparently consisting of one single insertion, was constituted by three stages: in the first stage the colpostat was used alone, in the next colpostat and tandem were left in place, and finally the colpostat was removed and the tandem was left in for the third stage to complete approximately 120 h. Regaud and Lacassagne did the basic radiobiologic investigation which provided the foundation for this technique. The Paris technique underwent considerable change when emphasis was given to the external irradiation by Coutard and his pupil Juan del Regato. Paterson and his group introduced meticulous physics to brachytherapy, that used ovoids adapted to the available vaginal lumen, and in which the isodose distribution around each ovoid followed the shape of the same. Both the Manchester and Paris techniques used low intensity brachytherapy, whereas the Stockholm technique used higher intensity (dose rate) sources. As these techniques evolved. the Paris method gave emphasis to external irradiation. whereas the Stockholm and Manchester methods continued emphasizing the internal component. Paterson’s classical clinical experiment comparing external irradiation prior to or after intracavitary irradiation lent support to the value of external irradiation in advanced cervical cancer. Fletcher added his contribution to del Regato’s and Paterson’s experiences. We all followed the external irradiation bandwagon, particularly in places with limited resources such as Puerto Rico. where we found that giving high dose external radiation, followed by one brachytherapy application. resulted in a high curability for all invasive stages of the disease. This experience has been duplicated in other centers. When the PCS cervix case material was analyzed, I was surprised by the findings that are presented in the article by L. V. Marcia1 ef al., which point toward better clinical results when two or more brachytherapy applications were used. We tried unsuccessfully to explain this difference with case selection, but the possibility exists that the observed better results, with two or more applications. are due to higher doses in Point A. The use oftwo or more brachytherapy applications in advanced cervical cancer has been practiced at many institutions. Kottmeier reported that when they used one application the results were poor. At the Mayo Clinic it used to be standard practice to administer two brachytherapy (radium) applications per week, during the 4 weeks of the external irradiation. Radiotherapists must recognize that to cure advanced cervical cancer we must deliver an adequate dose to the paracervical reference point (point A) and to the lateral pelvic wall. lntracavitary brachytherapy is useful to deliver a good dose at Point A. but for adequate irradiation of the lateral pelvic wall we must use external irradiation. Although the data in our article suggest that two or more brachytherapy applications are a convenient way of raising the dose at point A. we must remember that most patients in the PCS survey also received a substantial amount of external irradiation.

W. F. REGINE, M.D. K. M. AYYANGAR, PHD. L. T. KOMARNICKY,M.D. N. BHANDARE,M.S. C. M. MANSFIELD,M.D.

Thomas Jefferson University Hospital Department of Radiation Oncology Bodine Center for Cancer Treatment Philadelphia. PA I9 107-5097

Clark, D. H.; Le, M. G.; Sarazin, D.; Lacombe, M. J.; Fontaine, F.; Travagli, J. P.; May-Levin, F.; Contesso, G.; Ar-

riagada, M. Analysis of local-regional relapses in patients with early breast cancers treated by excision and radiotherapy: experience of the Institut Gustave-Roussy. Int. J. Radiat. Oncol. Biol. Phys. I I: 137-45; 1985. 2. Fisher, E. R.; Sass, R.; Fisher, B.; Gregorio, R.; Brown, R.; Wickerham, L. Pathologic findings from the National Surgical Adjuvant Breast Project (Protocol 6) II. Relation of local breast recurrence to multicentricity. Cancer 57: I7 I724; 1986. 3. Krishnan, L.; Mansfield, C. M.; Jewell, W. R.; Reddy, E. K.; Thomas, J. H.; Krishnan, E. C. Breast conservation treatment with perioperative interstitial irradiation. Am. J. Clin. Oncol. (CCT) 10(5):383-386; 1987. 4. Recht, A.; Silen, W.; Schnitt. S. J.; Connolly, J. L.; Gelman, R. S.; Rose, M. A.; Silver, B.; Harris, J. R. Time-course of local recurrence following conservative surgery and radiotherapy for breast cancer. Int. J. Radiat. Oncol. Biol. Phys. 15:255-261: 1988.

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I. J. Radiation Oncology 0 Biology 0 Physics

The social and economic burden on patients and radiotherapy facilities imposed by two or more brachytherapy applications are obvious. Consequently, it would be. desirable to compare in a randomized trial one versus two or more brachytherapy applications, adding external irradiation in both groups, and administering comparable doses in point A and the lateral pelvic wall. VICTORA. MARCIAL,M.D., F.A.C.R.

Radiation Oncology Division U. of Puerto Rico Cancer Ctr. G.P.O. Box 5067 San Juan, PR 00936

January 199 1,Volume 20, Number 1 I. Decker, D. G.; Van Herik, M. Survival in invasive carcinoma of the cervix five to ten years after radiation therapy. Am. J. Roent., Rad. Ther. Nut. Med. 85:488-496; 1961. 2. de1 Regato, J. A. The role of roetgen therapy in the treatment of cancer of the uterine cervix. Am. J. Roent., Rad. Ther. Nut. Med. 68:63-66; 1952. 3. Fletcher, G. H.; Caldenjn, R. Positioning of Pelvic Portals for External irradiation in carcinoma of the uterine cervix. Radioloav _- 67: 359-370; 1956. 4. Kottmeier, H. L. Current treatment of carcinoma of the cervix. Am. J. Obst. Gvnecol. 76243-251: 1958. 5. Marcial, V. A. Carcinoma of the cervix-present status and future. Cancer 39:945-958; 1977.