Radiation therapy for primary vaginal carcinoma

TRImodal DEfinitive invasive vagiNal carcinoma Treatment (TRIDENT protocol): how a standardized approach may change prognostic outcomes

OBJECTIVE

Vaginal carcinoma is a rare malignancy accounting for 1-2% of all gynecological cancers. Surgery has a limited role, while definitive radiotherapy-chemotherapy followed by interventional radiotherapy is considered a valid alternative. The aim of the TRIDENT (TRImodal DEfinitive invasive vagiNal carcinoma Treatment) pilot study was to report the results of a modern standardized trimodal protocol treatment consisting of image guided definitive radiotherapy-chemotherapy followed by image guided interventional radiotherapy in terms of safety and efficacy.

METHODS

Between January 2019 and December 2021, we analyzed 21 consecutive patients with primary vaginal cancer who had received radiotherapy-chemotherapy followed by interventional radiotherapy. The primary study endpoint was local control, and secondary endpoints were metastasis free survival, overall survival, and rate and severity of acute and late toxicities.

RESULTS

14 patients had FIGO (International Federation of Gynecology and Obstetrics) stage II, five patients had stage III, and two had stage IVB disease. Median total external beam radiotherapy dose for the tumor was 45 Gy. Median total dose on positive nodes was 60 Gy. Median total dose for interventional radiotherapy was 28 Gy over four high dose rate fractions to achieve between 85 and 95 Gy equivalent dose, in 2 Gy fractions (EQD2)α/β10, to the high risk clinical target volume, and 60 Gy EQD2α/β10 to the intermediate risk clinical target volume. All patients received weekly platinum based chemotherapy. Median follow-up was 20 months (range 10-56 months). Two year actuarial local control, metastasis free survival, and overall survival rate were 79.4%, 90.5%, and 79.4%, respectively. In terms of acute toxicity, there were no grade 4 events and only one acute grade (G) 3 toxicity (skin). Only vaginal stenosis (G3) was documented 12 months after therapy due to late toxicity.

CONCLUSIONS

In this study, definitive radiotherapy-chemotherapy followed by interventional radiotherapy was a safe and effective treatment modality for primary vaginal cancer.

Vaginal cancer treated with curative radiotherapy with or without concomitant chemotherapy: oncologic outcomes and prognostic factors

BACKGROUND

Vaginal cancer is a rare disease for which prospective randomized trials do not exist. We aimed to assess survival outcomes, patterns of recurrence, prognostic factors, and toxicity in the curative treatment using image-guided radiotherapy (RT).

METHODS

In this retrospective review, we identified 53 patients who were treated at a single center with external beam radiotherapy and brachytherapy with or without concomitant chemotherapy from 2000 to 2021.

RESULTS

With a median follow-up of 64.5 months, the Kaplan-Meier 2-, 5-, and 7-year overall survival (OS) was found to be 74.8%, 62.8%, and 58.9%, respectively. Local and distant control were 67.8%, 65.0%, and 65.0% and 74.4%, 62.6%, and 62.6% at 2, 5, and 7 years, respectively. In univariate Cox proportional hazards ratio analysis, OS was significantly correlated to FIGO stage (hazard ratio [HR] 1.78, p = 0.042), postoperative RT (HR 0.41, p = 0.044), and concomitant chemotherapy (HR 0.31, p = 0.009). Local control rates were superior when an equivalent dose in 2-Gy fractions (EQD2) of ⩾65 Gy was delivered (HR 0.216, p = 0.028) and with the use of concurrent chemotherapy (HR 0.248, p = 0.011). Not surprisingly, local control was inferior for patients with a higher TNM stage (HR 3.303, p = 0.027). Minimal toxicity was observed with no patients having documentation of high-grade toxicity (CTCAE grade 3+).

CONCLUSION

In treatment of vaginal cancer, high-dose RT in combination with brachytherapy is well tolerated and results in effective local control rates, which significantly improve with an EQD2(α/β=10) ⩾65 Gy. Multivariate analyses revealed concomitant chemotherapy was a positive prognostic factor for overall and progression-free survival.

Definitive radiotherapy with image-guided adaptive brachytherapy for primary vaginal cancer

Primary vaginal cancer is a rare cancer and clinical evidence to support recommendations on its optimal management is insufficient. Because primary vaginal cancer resembles cervical cancer in many aspects, treatment strategies are mainly adopted from evidence in locally advanced cervical cancer. To date, the organ-sparing treatment of choice is definitive radiotherapy, consisting of external beam radiotherapy and brachytherapy, combined with concurrent chemotherapy. Brachytherapy is an important component of the treatment and its steep dose gradient enables the delivery of high doses of radiation to the primary tumour, while simultaneously sparing the surrounding organs at risk. The introduction of volumetric CT or MRI image-guided adaptive brachytherapy in cervical cancer has led to better pelvic control and survival, with decreased morbidity, than brachytherapy based on x-ray radiographs. MRI-based image-guided adaptive brachytherapy with superior soft-tissue contrast has also been adopted sporadically for primary vaginal cancer. This therapy has had promising results and is considered to be the state-of-the-art treatment for primary vaginal cancer in standard practice.

Modern development of high-dose-rate brachytherapy

Brachytherapy is an invasive therapy with placement of radiation source into or near the tumor. The difference between planning target volume and clinical target volume is minimal, and the dose out of the tumor reduces rapidly due to the inverse-square law. High-dose-rate brachytherapy enables three-dimensional image guidance, and currently, tumor dose as well as doses of the surrounding normal structures can be evaluated accurately. High-dose-rate brachytherapy is the utmost precision radiation therapy even surpassing carbon ion therapy. Biological disadvantages of high-dose rate have been overcome by the fractional irradiation. High-dose-rate brachytherapy is indispensable in the definitive radiation therapy of cervical cancer. Also in prostate cancer and breast cancer, high-dose-rate brachytherapy plays a significant role. Brachytherapy requires techniques and skills of radiation oncologists at the time of invasive placement of the radiation source into the tumor area. Education of young radiation oncologists is most urgent and important.

Hyaluronic acid gel injection in rectovaginal septum reduced incidence of rectal bleeding in brachytherapy for gynecological malignancies

PURPOSE

The purpose of this study was to report our initial clinical results of hyaluronic acid gel injection (HGI) in the rectovaginal septum (RVS) to reduce the incidence of rectal bleeding in vaginal brachytherapy for gynecologic malignancies.

METHODS AND MATERIALS

Since 2008, CT based image-guided adaptive brachytherapy (IGABT) was initiated, and since 2015, HGI in the RVS was introduced in our institution. Vaginal cylinder with or without tandem or additional interstitial needles were applied for patients with gynecologic malignancies. Rectum dosimetric parameters and incidence of late rectum bleeding were compared between patients with and without HGI in the RVS.

RESULTS

Between May 2008 and October 2017, 83 patients with gynecologic malignancies were treated with IGABT involving vaginal cylinder. Eleven patients who were treated for palliative intention were excluded, and 72 patients were subjected to the analysis. Of the total 72 patients 46 were with uterine cervical cancer, 19 uterine corpus cancer, five vaginal cancer, one vulvar cancer, and one ovarian cancer. Fifteen and 57 patients were irradiated with and without HGI in the RVS, respectively. With a median follow-up period of 57.7 (4.7-123.1) months, 30 (41.7%) patients suffered from radiation-related rectal bleeding. Patients with HGI in the RVS had a statistically significant lower incidence of rectal bleeding compared with those without it (13.3% vs. 49.1%, p = 0.01).

CONCLUSIONS

HGI in the RVS reduced the incidence of late rectal bleeding for patients with gynecologic malignancies treated by vaginal cylinder and was not associated with HGI-procedure-related adverse events.

Outcomes of vaginal squamous cell carcinoma of patients treated with radiation therapy: a series of 37 patients from a single expert center

INTRODUCTION

The aim is to assess the outcome of patients treated for vaginal carcinoma with radiation therapy in terms of long-term tolerance and survival.

MATERIALS AND METHODS

This single-center retrospective study included patients with squamous cell carcinoma of the vagina treated with pelvic external beam radiation therapy (EBRT) with or without vaginal brachytherapy (VB) between 1990 and 2013.

RESULTS

Thirty-seven patients were included with stage I (24%), II (60%), III (8%), or IV (8%) vaginal tumors. Median age was 66 years (range 27-86 years). Median tumor size was 4 cm (range 0.7-12 cm). Seven patients underwent first intention surgery. The 37 patients received pelvic EBRT (45 Gy) with inguinal irradiation in 57% of cases. Fifteen (41%) received concurrent chemotherapy. Low-dose supplemental VB was performed in 31 patients (84%) (median dose: 20 Gy). Median follow-up was 59 months (range 7-322 months). Four patients (11%) had late grade 3-4 complications. Relapse occurred in 11 patients (30%), five of them locally. The 5-year relapse-free and cancer-specific survival rates were 68% and 76%, respectively. Surgery and concurrent chemotherapy did not seem to have an impact on the course of the disease.

CONCLUSION

In our experience, pelvic EBRT leads to prolonged survival with acceptable long-term toxicity in patients with squamous cell carcinoma of the vagina.

Definitive Radiotherapy in Invasive Vaginal Carcinoma: A Systematic Review

AIM

This study systematically reviews the recent literature on the role of definitive radiotherapy (RT) in the management of vaginal cancer (VC) and presents comprehensive data on clinical outcomes and toxicity.

METHODS

The authors performed a literature search using PubMed (2007-2016) to identify all prospective and retrospective studies that have been published on RT in invasive VC.

RESULTS

Of the 199 identified studies, 13 met the inclusion criteria. All studies had a retrospective design. Overall, 793 patients (median, 45; range, 26-138) were included. A high heterogeneity was found across studies in terms of RT techniques, assessment criteria, and reported outcomes. The majority of the patients were treated with a combination of external beam RT and brachytherapy (74.2%). Acute and late grade ≥3 toxicity rates ranged from 0.0% to 24.4% (median, 8.7%) and from 0.0% to 22.5% (median, 12.8%), respectively. The 5-year local control rates ranged between 39% and 79%. The 5-year overall survival ranged between 34% and 71.0% (median, 63.5%). Early stage of the disease (International Federation of Gynecology and Obstetrics stages I-II vs. III-IV), small tumor size (<4 cm), previous hysterectomy, high pretreatment/treatment hemoglobin levels (≥12/12.5 mg/dL), and patients' age <70 or <64 years were correlated with better clinical outcomes.

CONCLUSION

Only retrospective studies, in a limited number, have been published on RT in VC in the past decade, with significant heterogeneity in terms of treatment characteristic and evaluation criteria. Clinical results were strongly influenced by tumor stage. Prospective randomized studies are needed to improve patients' outcomes, especially in advanced-stage disease.

IMPLICATIONS FOR PRACTICE

This study systematically reviews the recent literature on the role of definitive radiotherapy in the management of vaginal cancer and presents comprehensive data on clinical outcome and toxicity. The prognosis of patients is dismal, with a 5-year overall survival of approximately 50%. Early stage of the disease, small tumor size, previous hysterectomy, high pretreatment/treatment hemoglobin levels, and patients' age were correlated with a better clinical outcome. A brachytherapy boost should be delivered, especially in patients with higher-stage disease. The addition of concurrent weekly cisplatin should be considered in most patients, and transfusion should be used to maintain high hemoglobin levels.

Japan Society of Gynecologic Oncology guidelines 2015 for the treatment of vulvar cancer and vaginal cancer

BACKGROUND

Vulvar cancer and vaginal cancer are relatively rare tumors, and there had been no established treatment principles or guidelines to treat these rare tumors in Japan. The first version of the Japan Society of Gynecologic Oncology (JSGO) guidelines for the treatment of vulvar cancer and vaginal cancer was published in 2015 in Japanese.

OBJECTIVE

The JSGO committee decided to publish the English version of the JSGO guidelines worldwide, and hope it will be a useful guide to physicians in a similar situation as in Japan.

METHODS

The guideline was created according to the basic principles in creating the guidelines of JSGO.

RESULTS

The guidelines consist of five chapters and five algorithms. Prior to the first chapter, basic items are described including staging classification and history, classification of histology, and definition of the methods of surgery, radiation, and chemotherapy to give the reader a better understanding of the contents of the guidelines for these rare tumors. The first chapter gives an overview of the guidelines, including the basic policy of the guidelines. The second chapter discusses vulvar cancer, the third chapter discusses vaginal cancer, and the fourth chapter discusses vulvar Paget's disease and malignant melanoma. Each chapter includes clinical questions, recommendations, backgrounds, objectives, explanations, and references. The fifth chapter provides supplemental data for the drugs that are mentioned in the explanation of clinical questions.

CONCLUSION

Overall, the objective of these guidelines is to clearly delineate the standard of care for vulvar and vaginal cancer with the goal of ensuring a high standard of care for all women diagnosed with these rare diseases.

Clinical characteristics of non-squamous cell carcinoma of the vagina

OBJECTIVE

The prognosis and vaginal disease control rate after treatment with radiotherapy or concurrent chemoradiotherapy (CCRT) are reported to be worse for primary non-squamous cell carcinoma (non-SCC) of the vagina than for squamous cell carcinoma (SCC) of the vagina. Our objective was to examine the clinicopathological characteristics of primary non-SCC of the vagina and suggest an appropriate treatment strategy.

MATERIALS AND METHODS

In a retrospective chart review, we identified patients with primary vaginal cancer who were treated in our hospital between 1990 and 2013. Twelve patients with histologically diagnosed non-SCC were identified. None of these cases was associated with in utero diethylstilbestrol exposure. Clinical data, including patient characteristics, stage, treatment outcome, and the site of recurrence, were recorded.

RESULTS

The 12 identified cases included 5 of clear cell carcinoma, 3 of adenocarcinoma, 2 of adenosquamous carcinoma, 1 of carcinosarcoma, and 1 of mucinous adenocarcinoma. The most common location of the tumor was the upper one third of the vagina (56%). Initial treatment involved surgery in 8 patients. Among them, 4 received adjuvant chemotherapy, 3 received adjuvant radiotherapy, and 1 received neither. The initial treatment among the remaining 4 patients was CCRT in 1, neoadjuvant chemotherapy in 2 (followed by CCRT or surgery), and best supportive care in 1. The last 3 patients had lung metastasis. Six patients experienced recurrence, including vaginal recurrence in 2 patients and lymphatic spread in 4 patients. Five of these 6 patients experienced hematogenous metastasis.

CONCLUSIONS

Despite the absence of in utero diethylstilbestrol exposure in our cases, clear cell adenocarcinoma accounted for 41.7% (5/12) cases. A favorable local control rate was achieved in all 12 cases, but the incidence of distant metastasis, especially to the lung, was high. Prevention of distant metastasis may be the key to treating patients with non-SCC of the vagina.

Prognostic Factors in Primary Vaginal Cancer: A Single Institute Experience and Review of Literature

BACKGROUND

Primary vaginal carcinoma is rare, accounting for 1-2 % of all gynecological malignancies. Being rare, most observations are based on retrospective and comparative analyses. This study was aimed to retrospectively analyze the prognostic factors and its relevance in the outcomes of primary vaginal cancers.

MATERIALS

Medical records of all cases of primary vaginal cancers, presented to Department of Oncology, from 2004 to 2012, at a tertiary care center in southern India, were retrieved from electronic medical records, and were analyzed.

RESULTS

The total number of cases was 32. Median age at presentation was 64.28 years. Squamous histology accounted for 84.4 %, with the rest being adenocarcinoma. Surgery was offered for five (15.6 %), and concurrent chemotherapy for 14 (43.8 %) patients. Three patients had only surgery. All others received radiotherapy. Twenty received external beam radiation (EBRT) and vaginal brachytherapy (VBT); seven only EBRT and two, adjuvant radiation. Five patients had residual disease; two, stage III, and three stage IV. Median follow-up was 55.83 months. Twelve patients were alive at last follow-up (37.5 %), while 14 were dead (43.8 %-8 of disease and 6 of other causes). Six patients were lost to follow-up (18.8 %). Twenty patients were disease free. Seven had recurrence, three loco-regional and four distant. Median overall survival (OS) was 86.1 months, disease-free survival (DFS) 90.17 months, and disease-specific survival (DSS) 97.13 months. When well and moderately differentiated tumors were taken together, the 5-year OS, DFS, and DSS rates were, 56.6, 64.3, and 82.3 %. For poorly differentiated tumors, median OS, DFS, and DSS were, 20.9, 14.6, and 20.9 months, with statistically significant advantage for better grade tumors, for DSS (p 0.050). Better 5-year OS, DFS, and DSS rates were observed for stage I + II group, with 54.9, 79.8, and 78.9 %, compared with advanced stage where the same were 54.8, 38.2, and 68.6 % (DFS-p 0.003, DSS-p 0.009). Grade and stage of tumor had statistically significant predictive value over the outcomes, while tumor size showed a significant trend. Patients treated with combination of EBRT and VBT fared well.

CONCLUSION

Our study could conclude that grade of differentiation was a significant predictor of poor survival as was stage of disease. Combination of VBT and external beam radiotherapy provides good DFS.

Definitive radiotherapy for primary vaginal cancer: correlation between treatment patterns and recurrence rate

The purpose of this study was to determine the outcomes and optimal practice patterns of definitive radiotherapy for primary vaginal cancer. Between 1993 and 2012, 49 patients were treated with definitive radiotherapy for primary vaginal cancer in three hospitals. Of these, 15 patients (31%) had clinically positive regional lymph node metastasis. A total of 34 patients (70%) received external beam radiotherapy with high-dose-rate brachytherapy (interstitial or intracavitary), and 8 (16%) (with small superficial Stage I tumors) were treated with local radiotherapy. The median follow-up was 33 months (range: 1-169 months). The 3-year overall survival (OS), disease-free survival (DFS), and loco-regional control (LRC) rates were 83%, 59% and 71%, respectively. In multivariate analysis, the histological type (P = 0.044) was significant risk factors for LRC. In Federation of Gynecology and Obstetrics (FIGO) Stage I cases, 3 of 8 patients (38%) who did not undergo prophylactic lymph node irradiation had lymph node recurrence, compared with 2 of 12 patients (17%) who underwent prophylactic pelvic irradiation. For Stage III-IV tumors, the local recurrence rate was 50% and the lymph node recurrence rate was 40%. Patients with FIGO Stage I/II or clinical Stage N1 had a higher recurrence rate with treatment using a single modality compared with the recurrence rate using combined modalities. In conclusion, our treatment outcomes for vaginal cancer were acceptable, but external beam radiotherapy with brachytherapy (interstitial or intracavitary) was needed regardless of FIGO stage. Improvement of treatment outcomes in cases of FIGO Stage III or IV remains a significant challenge.