Radiothérapie des cancers du col et de l’endomètre

Radiotherapy of cervical cancer

External beam radiotherapy and brachytherapy are major treatments in the management of cervical cancer. For early-stage tumours with local risk factors, brachytherapy is a preoperative option. Postoperative radiotherapy is indicated according to histopathological criteria. For advanced local tumours, chemoradiation is the standard treatment, followed by brachytherapy boost, which is not optional. We present the update of the recommendations of the French Society of Oncological Radiotherapy on the indications and techniques for external beam radiotherapy and brachytherapy for cervical cancer.

[Pelvic irradiation and hematopoietic toxicity: A review of the literature]

Pelvic bone marrow is the site of nearly 50% of total hematopoiesis. Radiation therapy of pelvic lymph node areas, and cancers located near the bony structures of the pelvis, exposes to hematological toxicity in the range of 30 to 70%. This toxicity depends on many factors, including the presence or absence of concomitant chemotherapy and its type, the volume of irradiated bone, the received doses, or the initial hematopoietic reserve. Intensity modulated radiation therapy allows the optimisation of dose deposit on at risk organs while providing optimal coverage of target volumes. However, this suggests that dose constraints should be known precisely to limit the incidence of radiation side effects. This literature review focuses firstly on pelvic lymph node areas and bony volumes nearby, then on the effects of irradiation on bone marrow and the current dosimetric constraints resulting from it, and finally on hematological toxicities by carcinologic location and progress in reducing these toxicities.

Impact of time to radiation therapy in adjuvant settings in endometrial carcinoma: A multicentric retrospective study

OBJECTIVE

Time to adjuvant treatment could have an impact on cancer prognosis. It is possible that robotic surgery lengthens the healing time of vaginal cuff after minimally invasive hysterectomy. The objective of this study was to state the impact of time to RT (TTR) on prognosis in endometrial carcinoma (EC) patients and to assess variables associated with TTR.

STUDY DESIGN

We conducted a multicentric retrospective study in two cancer centers. We included EC patients, between January 1996 and January 2016. We searched variables associated with TTR and impact of TTR on end-points: local recurrence-free survival, metastatic-free survival, event-free survival and overall survival.

RESULTS

329 patients were included and 279 were analyzed for TTR impact. Robotic surgery was associated with shorter TTR (8 weeks, 8.9 w for laparotomy, 9.2 w for laparoscopy). Pelvic lymphadenectomy, para-aortic lymphadenectomy, discussion in multidisciplinary meeting and treatment center was independently associated with TTR. No impact of TTR was shown on metastatic-free survival, event-free survival and overall survival but there was a trend of a decreased local recurrence rate in case of prolonged TTR (HR_{continuous variable} = 1.08; CI95 %: 0.97-1.2).

CONCLUSION

Our study did not show any impact of treatment delay on survival end-points although prolonged TTR could moderate the benefit of radiotherapy on local control rate. Surgical route was not associated with TTR, particularly robot-associated laparoscopy did not lengthen treatment delay. TTR seems dependent of health-care organization and could represent a quality criterion of EC care for institutions.

Impact of vaginal brachytherapy in intermediate and high-intermediate risk endometrial cancer: a multicenter study from the FRANCOGYN group

Objective

According to recent European Society of Medical Oncology, European Society of Gynaecological Oncology and European Society of Radiotherapy and Oncology guidelines, adjuvant vaginal brachytherapy (VB) is optional in patients with intermediate risk (IR) and high-intermediate risk (HIR) endometrial cancer (EC). The aim of this French retrospective, multicenter study was to assess the impact of VB in these groups on local recurrence rate, local recurrence-free survival (RFS) and overall survival (OS).

Methods

Data of 191 patients with IR and HIR EC who underwent primary surgery with or without VB and no other adjuvant treatment between 2000 and 2016 were extracted from the FRANCOGYN database. Rate of local recurrence, OS and local RFS in these two groups were compared using the Kaplan-Meier method.

Results

The number of patients with IR and HIR EC were 118 and 73 respectively. VB was used in 92 patients in IR group and 43 in HIR group. Median follow-up was 22 months. In the HIR group, the local recurrence rate was significantly higher in the no adjuvant therapy group in comparison with the VB group (16.7% and 0% respectively, p=0.02). There was also a significant improvement in local RFS (p=0.01) in VB group. In IR EC, there is no significant difference on local recurrence rate (4.2% and 3.2%, respectively, p=1.00) or local RFS (p=0.54) between the two groups.

Conclusions

VB is an efficient adjuvant treatment for patients with HIR EC. VB is not associated with an improvement of RFS or OS in IR EC patient.

[Radiotherapy for HIV-infected patients]

Since the advent of highly active antiretroviral therapy, cancer incidence is still 2 to 3-fold higher in patients infected by human immunodeficiency virus (HIV) than in the general population, with an increased incidence of malignancies not associated with acquired immunodeficiency syndrome (AIDS). HIV-infected patients cancer treatment does not differ from that in the general population. However, the management of those patients have some particularities due to preexisting comorbid conditions, including metabolic, cardiovascular, renal or hepatic complications and the risk for potential drug - drug interactions in HIV-infected patients. In this review, we described efficacy and tolerance of radiotherapy with or without chemotherapy in this frail population treated for cancer. Utilization of modern radiotherapy techniques such as intensity-modulated radiotherapy may improve the treatment tolerance.

[Doses to organs at risk for conformational and stereotactic radiotherapy: Bladder]

Bladder dose constraints in case of conformational radiotherapy/intensity-modulated radiotherapy and stereotactic radiotherapy are reported from the literature, in particular from the French radiotherapy society RECORAD recommendations, according to the treated pelvic tumor sites. The dose-volume effect on urinary toxicity is not clearly demonstrated, making difficult to establish absolute dose constraints for the bladder. In case of high-dose prostate cancer radiotherapy, the bladder dose constraints are: V60Gy<50% and maximum dose<80Gy for standard fractionation and V60Gy<5%, V48Gy<25% and V41Gy<50% for moderate hypofractionation (20 fractions of 3Gy). In case of prostate stereotactic radiotherapy (five fractions of 7.25Gy), the most frequent dose constraints in the literature are V37Gy<10cm³ and V18Gy<40%. In case of conformational radiotherapy of cervix cancer, postoperative endometrium, anal canal and rectum, the recommendations are V40Gy<40% and D2% lower than the prescribed dose.

[Comparison of survival and chronic gastrointestinal toxicities in patients with locally advanced cervical cancer, treated by conventional or intensity-modulated radiation technique]

PURPOSE

To evaluate prospectively chronic gastrointestinal toxicity in patients with cervical cancer treated with conventional irradiation or with intensity-modulated irradiation (IMRT).

PATIENTS AND METHODS

Between June 2005 and September 2013, 109 patients underwent external radiotherapy followed by brachytherapy for cervical cancer at the "Institut de Cancérologie de Lorraine". Each patient receiving IMRT was paired with a patient receiving conventional radiotherapy on the following criteria: concomitant chemotherapy, additional nodal dose, treatment of para-aortic lymph node area, age. The toxicity collection was prospective using the RTOG scale. The main objective was to compare the incidence of gastrointestinal toxicity chronic between the two groups. In a second time, the influence of dosimetric parameters on chronic GI toxicity was investigated. Comparisons of acute toxicity, chronic genitourinary toxicities, overall survival, disease-free survival were secondary objectives.

RESULTS

Sixty-six patients were able to be matched. Overall survival at 36 months was 71% in the conventional radiotherapy group against 73% in the IMRT group (P=0.54). There was no significant difference between the two groups in terms of digestive chronic toxicity (P=0.17), nor in terms acute gastrointestinal toxicities (P=0.6445) and genitourinary (P=0.5724). IMRT spared significantly small bowel (P=0.0006) and rectum (P=0.0046) from 30Gy dose, and bladder from 45Gy (P<0.001). The incidence of genitourinary toxicity was significantly different between the two groups (P=0.03) in favor of conventional radiotherapy.

CONCLUSION

Our study does not seem to show significant difference in the occurrence of chronic gastrointestinal toxicities between the two groups. Clinical efficacy seems comparable. Larger studies with longer follow-up period should be conducted.