Cervical brachytherapy technique for locally advanced carcinoma of the cervix in a patient with septate uterus

Abstract

Purpose: To describe an approach to cervical brachytherapy in a patient with congenital septate uterus and locally advanced cervical carcinoma.

Material and methods: The patient is a 34-year-old female with septate uterus presenting with pelvic pain. Workup demonstrated a stage IIB cervical adenocarcinoma with imaging evidence of an involved right external iliac lymph node. The patient received whole pelvic radiation, with concurrent weekly cisplatin (40 mg/m(2)), to a dose of 45 Gy in 25 fractions followed by a parametrial boost of 5.4 Gy and an additional nodal boost of 9 Gy.

Results: The patient was initiated on cervical brachytherapy following fraction 23 of pelvic radiation. To conform to her septated uterus, a Rotte-Y tandem was used. Additionally, 2 CT-compatible ovoids were placed in the vaginal apex to enhance dose distribution and coverage of the target volume. Each fraction of brachytherapy was performed with CT-based planning. A high-risk clinical target volume (HR-CTV) and normal structures were defined and constrained per American Brachytherapy Society (ABS) and Groupe Européen de Curiethérapie/European Society for Therapeutic Radiology and Oncology (GEC-ESTRO) guidelines. The brachytherapy dose was 27.5 Gy in 5 fractions of 5.5 Gy each, prescribed to the HR-CTV.

Conclusions: Herein, we report the first documented case of cervical brachytherapy in a patient with septate uterus and locally advanced cervical carcinoma. Using CT-guided planning, in conjunction with the ABS and GEC-ESTRO guidelines, the patient was effectively treated with adapted cervical brachytherapy, meeting criteria for HR-CTV coverage and normal tissue tolerances.

Keywords: Rotte-Y tandem; brachytherapy; cervical cancer; septate uterus.

Fig. 1

Pretreatment (A) and pre-brachytherapy (B) MRI images in the axial and sagittal planes demonstrating a septate uterus with a large tumor involving the cervix and parametria. The pre-brachytherapy MRI images were obtained at fraction 18 of whole pelvic radiation with concurrent cisplatin chemotherapy, and demonstrate a partial response to therapy

Fig. 2

Photograph of the assembled Rotte-Y applicator prior to placement

Fig. 3

Photograph of the completely assembled treatment apparatus including the Rotte-Y applicator attached to a pair of colpostats with large ovoids via a simple bridge

Fig. 4

Three-dimensional graphical rendering of the assembled treatment apparatus in the coronal (A) and right anterior-lateral (B) views, diagraming the anatomic relationship of the apparatus to the HR-CTV (red) and normal structures including the bladder (yellow), rectum (blue), and the sigmoid colon (green). The red dots within the tandems and colpostats represent the planned dwell positions of the HDR ¹⁹²Ir source

Fig. 5

Representative coronal image from the final brachytherapy plan. The HR-CTV is outlined with a reddashed line. Isodose distribution is demonstrates adequate coverage of the HR-CTV with a conformal brachytherapy plan. The red dots within the tandems and colpostats represent the planned dwell positions of the HDR ¹⁹²Ir source