Toshiki Ikawa

Trends in radiotherapy use and implementation challenges among patients with cervical cancer: a multicenter study in Osaka, Japan

ABSTRACT Since 2018, the staging system and guidelines for cervical cancer have been revised in Japan. Here, we analyzed trends in radiotherapy use among patients with cervical cancer in Osaka Prefecture, Japan. We obtained records from hospital-based cancer registries (2016–23) linked to Diagnosis Procedure Combination data (2019–23), from 67 nationally or prefecturally designated cancer care hospitals. Eligible patients had epithelial or neuroendocrine cervical cancer, excluding those with clinical stage 0 or unknown clinical stage with pathological stage 0. Between 2016 and 2023, the number of patients per year remained stable (717–787); the number of stage IB–IIA (FIGO 2018) cases decreased, whereas that of stages IIB or IIIC (T1–2) cases increased. The number of patients receiving radiotherapy as initial treatment increased from 229 in 2016 to 294 in 2023; this was accompanied by a decline in surgical treatment. The proportion of patients undergoing radiotherapy increased from 11.9% to 17.2% for stage IB–IIA, from 55.6% to 71.7% for stage IIB and from 38.0% to 69.5% for stage IIIC (T1–2). Among 11 institutions providing brachytherapy, the number of radiotherapy cases increased at three, whereas it remained stable or declined at the other eight. These findings indicate a growing trend in radiotherapy use for cervical cancer in Osaka Prefecture; however, the increase varied by institution. To sustain cervical cancer radiotherapy services, further studies may be needed to assess the adequacy of brachytherapy staffing, explore the financial feasibility of brachytherapy equipment, and examine the potential implications of brachytherapy centralization.

Secondary Lower‐Body Sarcomas in Cervical Cancer Survivors Following Surgery, Radiotherapy, or Both: A Population‐Based Study

ABSTRACT Secondary sarcomas in cervical cancer survivors are understudied. We investigated the incidence and subtypes of secondary sarcomas by treatment modalities, the prognosis of secondary sarcomas, and whether surgery plus radiotherapy increases angiosarcoma incidence. This population‐based retrospective cohort study analyzed Osaka Cancer Registry data on women aged 20–84 years diagnosed with cervical cancer (1980–2015), treated with surgery, radiotherapy, or both. Patients with distant metastases, survival time < 1 year, or missing data were excluded. We included 7591 patients with invasive cancer treated with surgery, 3882 with radiotherapy, and 4090 with surgery plus radiotherapy and 13,205 with carcinoma in situ treated with surgery. We assessed the first lower‐body sarcoma occurrence ≥ 1 year post‐diagnosis. Sarcomas developed in 6 patients treated with surgery (0 angiosarcomas), 10 with radiotherapy (1 angiosarcoma), and 19 with surgery plus radiotherapy (9 angiosarcomas). At 10 years, the cumulative incidence was 0.083% (95% confidence interval [CI], 0.024%–0.24%) for radiotherapy and 0.21% (95% CI, 0.10%–0.41%) for surgery plus radiotherapy, higher than that for surgery (invasive, 0.013%; in situ, 0.028%) ( p  < 0.001). Angiosarcoma incidence was higher with surgery plus radiotherapy (0.080%; 95% CI, 0.023%–0.23%) than with radiotherapy (0.028%; 95% CI, 0.003%–0.16%) ( p  = 0.029). Among patients diagnosed with sarcoma after radiotherapy or surgery plus radiotherapy, the 1‐year overall survival rate was 33.3% (95% CI, 19.6%–56.8%). Radiotherapy, alone or combined with surgery, increased secondary lower‐body sarcoma incidence compared with surgery. To our knowledge, this is the first population‐based study to suggest that surgery plus radiotherapy is associated with angiosarcoma in cervical cancer survivors.