Possibilities of Modern Radiation Therapy for Locally Advanced Endometrial Cancer

Purpose: Analysis of radical radiotherapy efficacy (combination of remote irradiation with simultaneous dose escalation to the tumor focus and subsequent intracavitary component) in a patient diagnosed with stage III endometrial cancer when surgical treatment is impossible. Assessment of the dynamics of the underlying disease and adverse events. The purpose of the study is to analyze the effectiveness of radical radiation therapy in a patient diagnosed with stage III endometrial cancer when surgical treatment is impossible.

Material and methods: We present a clinical case of a patient with inoperable stage III endometrial cancer (histologic variant-highly differentiated adenocarcinoma) with metastasis to the lower third of the vagina. The first stage was a course of remote radiotherapy on a linear gas pedal VarianTrueBeamSTx on the uterus, vagina, paravaginal tissues, pelvic lymph nodes up to a total dose of 50 Gy and simultaneous dose intensification on the area of tumor focus in the lower third of the vagina up to a total dose of 62.5 Gy. The method of dose administration was rotational radiotherapy with intensity modulation of photon radiation (Volume-modulated arc therapy ‒ VMAT).

The second stage was a course of intracavitary (contact, brachytherapy) radiotherapy on MultiSource HDR device with ⁶⁰Co ionizing radiation source. A gynecological two-channel applicator was used during treatment. The plan of each treatment session was developed based on CT images on the SagiPlan planning station. Intracavitary radiation therapy mode – single dose of 6 Gy, 4 fractions were performed.

The effect of radiation therapy was assessed by MRI of pelvic organs with intravenous contrasting immediately after treatment and further at intervals of every 3 months.We present a clinical case of a 71 year old female patient diagnosed with stage III endometrial cancer (well-differentiated adenocarcinoma), with adenocarcinoma metastasis to the lower 1/3 of the vagina. Planning of radiotherapy and radiation therapy in a patient with inoperable endometrial cancer with simultaneous escalation of the dose of ionizing radiation to the area of ​​metastasis in the vagina during the remote component and subsequent intracavitary boost to the uterine area. Study of the results of radiation therapy.

Results: After treatment, MRI data showed complete regression of the tumor nidus in the vagina and reduction of the nidus in the uterine body (more 50 %). Long-term control of the tumor process in the patient, confirmed by clinical and radiological studies (MRI of the pelvic organs), was also achieved.The capabilities of modern radiation therapy make it possible to carry out radical treatment of patients with endometrial cancer in clinical cases when it is necessary to increase the dose of ionizing radiation to a separate tumor focus, without exceeding the tolerable levels of radiation exposure to risk organs. This approach makes it possible to achieve remission in real clinical practice.

Conclusion: The capabilities of modern radiation therapy allow radical treatment of patients with inoperable endometrial cancer in clinical cases when it is necessary to increase the dose of ionizing radiation to a separate tumor focus without exceeding tolerance levels of radiation loads on risk organs. This approach makes it possible to achieve remission in real clinical practice.