Whole pelvic intensity-modulated radiotherapy for gynecological malignancies: A review of the literature

Abstract

Radiation therapy has long played a major role in the treatment of gynecological malignancies. There is increasing interest in the utility of intensity-modulated radiotherapy (IMRT) and its application to treat gynecological malignancies. Herein, we review the state-of-the-art use of IMRT for gynecological malignancies and report how it is being used alone as well as in combination with chemotherapy in both the adjuvant and definitive settings. Based on dosimetric and clinical evidence, IMRT can reduce gastrointestinal, genitourinary, and hematological toxicities compared with 3D-conformal radiotherapy for gynecologic malignancies. We discuss how these attributes of IMRT may lead to improvements in disease outcomes by allowing for dose escalation of radiation therapy, intensification of chemotherapy, and limiting toxicity-related treatment breaks. Currently accruing trials investigating pelvic IMRT for cervical and endometrial cancers are discussed.

Keywords: Cervical; Endometrial; Gynecologic; IMRT; Radiation therapy.

Figure 1

Beam arrangement and treatment planning images. Representative treatment planning images for a 48 year old female with stage IB1 cervical carcinoma treated with concurrent cisplatin. Plans were generated using A) a two-field AP-PA technique, with images depicted in the B) axial, C) coronal, and D) sagittal planes. Plans were also generated using E) a four-field (AP-PA and opposed laterals) technique, with images depicted in the F) axial, G) coronal, and H) sagittal planes. Lastly, plans were generated using I) a seven-field IMRT technique, with images depicted in the J) axial, K) coronal, and L) sagittal planes. All plans delivered 45Gy in 1.8Gy daily fractions. The same slices from the same CT data set are depicted for Figures 1A, 1E, and 1I; Figures 1B, 1F, and 1J; Figures 1C, 1G, and 1K; and Figures 1D, 1H, and 1L. The aqua volume is the nodal PTV, and the magenta volume is the vaginal cuff PTV. Dose color wash coding: blue=50% to red=global max above 100%. This patient was also treated with a vaginal cuff boost using high dose rate brachytherapy.