Although uterine cervical cancer occurring in patients with uterine prolapse has been sporadically reported to date, the incidence rate of this condition is unknown. Based on the information we obtained, the rate is estimated to range from 0.14 to 1.00% [
4,
7]. Moreover, no standard treatment for uterine cervical cancer occurring in women with uterine prolapse has been established. Whether this condition should be treated with surgery-based or RT-based therapy remains to be determined [
7,
17]. The detailed irradiation procedures used for RT administered for uterine cervical cancer associated with uterine prolapse have been reported in only three cases [
8‐
10] (Table
2), and this is the first reported vaginal cancer of this condition complicated by intrauterine adhesions. Among these previous cases, EBRT alone was administered in one case and a combination of EBRT and ICBT was applied in the other two. Uterine prolapse was spontaneously reduced before EBRT in one case, and reduction was achieved by pessary use and perineoplasty before EBRT in another case [
8,
10]. In the third case, the uterine prolapse could not be reduced before EBRT, and radiation cystitis also occurred [
9]. When EBRT is administered, reduction of uterine prolapse and hysterectomy are recommended before EBRT to reduce the risks of visceral injury and vesicovaginal or rectovaginal fistulas of the surrounding organs [
18,
19]. When BT is administered, however, the exposure doses to the rectum and bladder can be reduced when the uterus remains prolapsed. In fact, the exposure doses delivered to the OARs by HDR ISBT were very low in our case. The standard procedure of RT for uterine cervical cancer is generally a combination of EBRT and ICBT [
20]. According to the National Comprehensive Cancer Network Clinical Practice Guidelines in Oncology for Cervical Cancer, BT alone is an option for very early disease, and ISBT is selected in rare cases in which ICBT is not feasible depending on the anatomy or tumor geometry [
20]. Furthermore, the American Brachytherapy Society recommends ISBT for cases involving a bulky lesion, a narrow vagina, the inability to enter the cervical os, extension to the lateral parametrium or pelvic side wall, and lower vaginal extension [
21]. ISBT was administered in our case because severe intrauterine adhesions inhibited ICBT. HDR ISBT is a therapeutic procedure performed by inserting 5 to 30 needle applicators from the perineum to the cervical cancer under general or spinal anesthesia. This procedure is often combined with ICBT and performed during the later stage or after completion of whole-pelvis EBRT [
22‐
24]. In the present case, we needed to plan RT with the lowest possible toxicity because of her advanced age and arrhythmia; therefore, only HDR ISBT was administered. Thus, neither gastrointestinal nor genitourinary toxicity was observed. Moreover, under local anesthesia only without the need for general or spinal anesthesia, direct insertion of plastic BT needles to the prolapsed uterus caused very little pain. No optimal dose of HDR ISBT for uterine cervical cancer has been determined. However, based on previous reports, the optimal dose per fraction ranges from 4 to 7 Gy for HDR ISBT, and the optimal total D
90 for HR-CTV (EQD2) ranges from 67.6 to 96.6 Gy when HDR ICBT and EBRT are combined [
23‐
25]. In one study, when stage ≥T3a tumors with a median HR-CTV of 29.8 cc were treated with a total D
90 for HR-CTV (EQD2) of 80.6 Gy, the local control rate was 83% [
23]. In another study, when FIGO stage ≥IIB tumors with a median HR-CTV of 103 cc were treated with a D
90 for HR-CTV (EQD2) of 67.6 Gy, the local control rate was 80% [
24]. Furthermore, when relatively small tumors measuring 2 to 5 cm were treated with a D
90 for HR-CTV (EQD2) of 89 Gy, the local control rate was 96.9% [
25]. Finally, when small tumors measuring ≤4 cm were treated with a total D
90 for HR-CTV (EQD2) of 69.0 Gy, the local control rate was 96% [
26]. In our case, the GTV was 19.4 cc, which is smaller than the HR-CTV described in previous reports. In the first treatment, we treated the total D
90 for GTV (EQD2) of 65.0 Gy appeared sufficient compared with these previous reports, but biopsy revealed residual squamous cell carcinoma. This first treatment dose may be insufficient if chemotherapy was not performed. We could add HDR ISBT with observation of the treatment effect by biopsy, and the total D
90 for GTV (EQD2) of 113.8 Gy appeared sufficient. No residual squamous cell carcinoma was detected after completion of the additional HDR ISBT. This additional procedure is advantageous over EBRT. The limitation of our case is the short follow-up period. When vaginal or uterine cervical cancer develops in women with uterine prolapse and intrauterine adhesions, HDR ISBT may be an effective therapeutic strategy with less adverse effects compared with EBRT.
Table 2
Cases of cervical/vaginal cancer in patients with uterine prolapse treated by radiation therapy
1 | 60 | IIIB | Large-cell nonkeratinizing squamous cell carcinoma | Reduced under sedation before RT | 50 Gy | None | None | 2 | 8 |
2 | 73 | IIA | W/D keratinizing squamous cell carcinoma | Irreducible | Pelvis 52.2 Gy | Intracavitary HDR 7.5 Gy × 3 | Vaginal hysterectomy | 60 | 9 |
3 | 72 | IIA2 | W/D squamous cell carcinoma | Reduced utilizing pessary before RT | Whole pelvis 45 Gy | Intracavitary tandem and ovoids HDR 6 Gy × 5 | None | 15 | 10 |
4 | 78 | I | Keratinizing squamous cell carcinoma | Not reduced | None | interstitial HDR 6 Gy × 14 | None | 3 | our case |