METHODS
We retrospectively reviewed the records of 150 patients with locally advanced cervical cancer treated
with curative chemoradiotherapy between 1999 and 2014 at our hospital.
RESULTS
The median follow-up period was 37.5 months (range: 5.6?186 months). All patients received both external
beam radiation therapy (EBRT) and intracavitary brachytherapy. EBRT was delivered with conventional
2-dimensional radiotherapy or 3-dimensional conformal radiotherapy (3DCRT). Eighty-seven
percent of patients received cisplatinum-based chemotherapy during EBRT. Total or nearly total remission
was achieved in 72% of patients. With a median follow-up duration of 37.5 months, 29% of patients
died, 13% of patients had local-regional recurrence, and 25% of patients had distant metastasis. The 2-,
5-, and 10-year overall survival rates were 76%, 62%, and 47%, respectively, and the progression-free
survival rates were 68%, 62%, and 58%, respectively. We evaluated prognostic factors for overall survival
and progression-free survival. The most important prognostic factor was the radiotherapy technique. The
survival curves were estimated by the Kaplan?Meier method, and differences were assessed using the
log-rank test; a p-value<0.05 was considered significant.
CONCLUSION
Chemoradiotherapy is an effective and tolerable treatment method for patients with cervical cancer.
These patients treated with 3DCRT have a better overall survival.
Keywords: Prognostic factors; Radiotherapy; Radiotherapy technique; Cervical cancer
While the standard treatment for patients with LACC
(stages IB2?IVA ) is concomitant chemoradiotherapy,
radical hysterectomy is used as the primary therapy for
patients with early-stage carcinoma (stages IA-IB1) of
the cervix.[
Here, we evaluated the treatment results and prognostic
factors in patients treated with chemoradiotherapy
and compared 2 different treatment techniques .
For planning 3DCRT, CT simulation images of the patients were taken (adjacent axial slice spacing, 2.5 mm; GE-Lightspeed64® computed tomography simulator; GE, Fairfield, USA). The target volumes and critical normal tissues (bowel, bladder, and rectum) were outlined on each CT slice.
Following EBRT, all patients underwent "Nucletron Microselectron IR-192" high-dose-rate brachytherapy, which was applied at a total dose of 28?30 Gy in 6-7- Gy fraction doses. Concurrent weekly cisplatin at 35?40 mg/m2 was administered intravenously during EBRT.
The survival curves were estimated by the Kaplan? Meier method, and differences were assessed using the log-rank test; p-values<0.05 were considered significant. Prognostic factors studied were age, tumor size (>4 cm, ?4 cm), stage, vaginal extension, pelvic wall involvement, parametrial extension, and radiotherapy technique (2DRT or 3DCRT). The level of significance was set at p<0.05. In addition, "stepwise cox regression analysis" was performed.
Whereas 2DRT was performed in 52 patients (35%),
3DCRT was performed in 98 patients (65%). Table
In total, 130 patients (87%) received cisplatin-based concomitant chemotherapy (35-40 mg/m2 once per week), whereas 10 patients did not receive concomitant chemotherapy because of extended field for the external irradiation of para-aortic lymph nodes, it was not evident whether 10 patients received chemotherapy.
With a median follow-up duration of 37.5 months (range: 5.6-186 months), 99 patients (66%) had no evidence of disease at the last follow-up. During follow-up, 43 patients (29%) had recurrence by imaging and clinical examination, 19 patients had loco-regional relapse, 37 patients had distant metastases, and 13 patients had both loco-regional and distant metastases. It was detected that the loco-regional relapse rate of 3DCRT was lower than that of 2DRT (2% and 33%, respectively) (p=0.001). Distant metastasis rates of 3DCRT and 2DRT were 19% and 38%, respectively (0.01).
The 2-, 5-, and 10-year overall survival (OS) and DFS rates were 76%, 62%, and 47% and 68%, 62%, and 58%, respectively.
Age (p=0.01), stage (p=0.001), vaginal extension (p=0.02), pelvic wall involvement (p=0.001), and radiotherapy technique (p<0.001) were found to be significant prognostic factors in terms of OS.
The radiotherapy technique was found to be the only significant prognostic factor for DFS (p<0.001). The radiotherapy technique was the most important factor according to stepwise cox regression analysis.
Survival rates were superior in patients receiving
3DCRT (Table
In the follow-up period, after the completion of radiotherapy, rectovaginal fistula and small bowel adhesion were observed in 2 patients, both of whom were treated with 3DCRT. Serious side effects were not observed in the other patients during or after radiotherapy.
The benefit of brachytherapy in terms of survival
and local control has been reported by Coia et al.[
Previous studies have confirmed age, performance
status, tumor diameter, and lymph node status as prognostic
factors of the progression-free rate for patients
with LACC.[
To the best of our knowledge, our study is one of the
few studies in the literature that has compared 3DCRT
and 2DRT techniques regarding survival in the longterm
follow-up period. In a study, the 5-year survival
rate for 2DRT and 3DCRT was found to be significantly
different (73.0% and 82.3%, respectively). Accompanying
comorbidities of these patients were also examined,
and patients with cervical cancer with more comorbidities
were found to have poorer survival rates.[
In 2013, a study compared conformal and conventional
radiotherapy techniques in 5 patients dosimetrically.[
In our study, the radiotherapy technique was the
most important prognostic factor. Patients receiving
3DCRT had superior survival rates and treatment responses.
The primary reason for this was that the error
risks arising from a potential geographic miss or
individual anatomical variations were reduced because
the target volume and critical normal tissues were determined
based on CT-simulation images. The other
reason was that 3DCRT demonstrated a better coverage
and dose homogeneity inside the CTV because of the
added segments to lateral fields.
Throughout pelvic radiotherapy or after the completion
of treatment, genitourinary or gastrointestinal side
effects have been shown.[
Modern technologies in radiotherapy delivery, such
as IMRT, allow greater sparing of normal tissues and provide highly conformal dose distributions. Although
advantages of EBRT in patients with LACC treated with
IMRT have been shown in terms of survival and side effects,
it may have disadvantages, such as motion or filling
of organs, and inhomogeneity within target volumes
may affect local control.[
Although the application of IMRT in patients with
definitive cervical cancer is not yet a standard approach,
prospective clinical studies are needed to evaluate the
comparative efficacy of IMRT and conventional or
3DCRT techniques.
Peer-review: Externally peer-reviewed.
Conflict of Interest: No potential conflict of interest relevant to this article was reported.
Authorship contributions: Concept - B.Ş.Ö.; Design - B.Ş.Ö., G.M.A.; Supervision - B.Ş.Ö., G.M.A., M.G.; Materials - B.Ş.Ö., G.M.A., M.N.Y., T.B.; Data collection &/or processing - B.Ş.Ö.; Analysis and/or interpretation - B.Ş.Ö., G.M.A.; Literature search - B.Ş.Ö., G.M.A.; Writing - B.Ş.Ö.; Critical review - B.Ş.Ö., G.M.A., A.F.K.