Treatment results for Stage Ib cervical cancer after stage subdivision by MRI evaluation

The authors analyzed treatment results for cervical cancer after subdividing Stage Ib into Stages Ib1 and Ib2 according to magnetic resonance imaging (MRI) information.

The subjects comprised 40 cases of Stage Ib cervical cancer treated by definitive radiotherapy in Kitasato University hospital and Tokyo University hospital from January 2000 to December 2008. The patients' ages ranged from 28 to 85 years (median: 68 years). The maximum tumor diameter measured with MRI ranged from undetectable to 60 mm (median: 25 mm). The authors classified tumors with the greatest dimension less than 40 mm as Stage Ib1 (29 cases) and those with the greatest dimension more than 40 mm as Ib2 (11 cases). All cases were treated with a combination of external beam irradiation and high-dose-rate intra-cavitary brachytherapy. Chemotherapy was combined with radiotherapy in 11 cases.

The follow-up time was from four to 109 months (median: 53 months). At the time of last observation, 37 cases survived, local recurrence was seen in none, and two cases showed distant metastasis. The two- and five-year overall survival rates of all cases were 97.5% and 89.5%, respectively. When a stage was subdivided and examined, the five-year overall survival rate of Stage Ib1 was 100% and that of Stage Ib2 was 50.5% (p = 0.001).

The authors suggest that the subdivision of stages using image information reflects the prognosis of Stage Ib cervical cancer.