Identification of oncological characteristics associated with improved overall survival in patients with adrenocortical carcinoma treated with adjuvant radiation therapy: Insights from the National Cancer Database

Efficacy and safety of adjuvant radiation therapy in localized adrenocortical carcinoma

Context

Adrenocortical carcinoma (ACC) is rare and have high rates of recurrence and mortality. The role of adjuvant radiation therapy (RT) in localized ACC was controversial.

Methods

We conducted a retrospective study in our center between 2015 and 2021 to evaluate the efficacy and safety of adjuvant RT in localized ACC. Overall survival (OS) and disease-free survival (DFS) were estimated using the Kaplan-Meier method. Cox proportional hazards regression models were used to estimate the independent risk factors. Adverse events associated with RT were documented according to the toxicity criteria of the radiation therapy oncology group (RTOG) and the common terminology criteria for adverse events (CTCAE v5.0).

Results

Of 105 patients with localized ACC, 46 (43.8%) received adjuvant RT after surgery. The median radiation dose was 45.0Gy (range:30.0-50.4) and median follow up time was 36.5 (IQR: 19.7-51.8) months. In comparison to the no adjuvant RT group, patients with adjuvant RT had better 3-year OS (87.9% vs 79.5%, P=0.039), especially for patients with ENSAT I/II stage (P=0.004). Adjuvant RT also improved the median DFS time from 16.5months (95%CI, 12.0-20.9) to 34.6months (95%CI, 16.1-53.0). Toxicity of RT was generally mild and moderate with six grade 3 events.

Conclusions

Postoperative adjuvant RT significantly improved OS and DFS compared with the use of surgery alone in resected ACC patients. Although this retrospective study on RT in localized ACC indicates that RT is effective in ACC, its findings need to be prospectively confirmed.

Efficacy and safety of radiation therapy in advanced adrenocortical carcinoma

BACKGROUND

International guidelines emphasise the role of radiotherapy (RT) for the management of advanced adrenocortical carcinoma (ACC). However, the evidence for this recommendation is very low.

METHODS

We retrospectively analysed all patients who received RT for advanced ACC in five European centres since 2000.

PRIMARY ENDPOINT

time to progression of the treated lesion (tTTP). Secondary endpoints: best objective response, progression-free survival (PFS), overall survival (OS), adverse events, and the establishment of predictive factors by Cox analyses.

RESULTS

In total, 132 tumoural lesions of 80 patients were treated with conventional RT (cRT) of 50-60 Gy (n = 20) or 20-49 Gy (n = 69), stereotactic body RT of 35-50 Gy (SBRT) (n = 36), or brachytherapy of 12-25 Gy (BT) (n = 7). Best objective lesional response was complete (n = 6), partial (n = 52), stable disease (n = 60), progressive disease (n = 14). Median tTTP was 7.6 months (1.0-148.6). In comparison to cRT20-49Gy, tTTP was significantly longer for cRT50-60Gy (multivariate adjusted HR 0.10; 95% CI 0.03-0.33; p < 0.001) and SBRT (HR 0.31; 95% CI 0.12-0.80; p = 0.016), but not for BT (HR 0.66; 95% CI 0.22-1.99; p = 0.46). Toxicity was generally mild and moderate with three grade 3 events. No convincing predictive factors could be established.

CONCLUSIONS

This largest published study on RT in advanced ACC provides clear evidence that RT is effective in ACC.

Bridging the Scientific Gaps to Identify Effective Treatments in Adrenocortical Cancer

Adrenocortical cancer (ACC) typically presents in advanced stages of disease and has a dismal prognosis. One of the foremost reasons for this is the lack of available systemic therapies, with mitotane remaining the backbone of treatment since its discovery in the 1960s, despite underwhelming efficacy. Surgery remains the only potentially curative option, but about half of patients will recur post-operatively, often with metastatic disease. Other local treatment options have been attempted but are only used practically on a case-by-case basis. Over the past few decades there have been significant advances in understanding the molecular background of ACC, but this has not yet translated to better treatment options. Attempts at novel treatment strategies have not provided significant clinical benefit. This paper reviews our current treatment options and molecular understanding of ACC and the reasons why a successful treatment has remained elusive. Additionally, we discuss the knowledge gaps that need to be overcome to bring us closer to successful treatment and ways to bridge them.

Association of tumor size and surgical approach with oncological outcomes and overall survival in patients with adrenocortical carcinoma

OBJECTIVES

To investigate the association of surgical approach with outcomes in patients with adrenocortical carcinomas smaller and larger than 6 cm in size.

METHODS

We reviewed the national cancer database for patients undergoing minimally invasive adrenalectomy (MIA) and open adrenalectomy (OA) from 2010 to 2017. To adjust for differences between patients undergoing MIA and OA, we performed propensity score matching within each size strata of ≤6 cm, 6.1 to 10 cm, and 10.1 to 20 cm. We fit generalized estmiating equations with a logit link function to assess for the association of surgical approach with positive surgical margins and a Cox proportional hazards model to assess for the association of surgical approach with overall survival.

RESULTS

We identified 364 patients that underwent MIA (182) and OA (182) in the matched cohort.  We noted 21% and 18% of patients undergoing MIA and OA had a positive surgical margin, respectively. We did not identify a significant association between surgical approach and positive surgical margins in the cohort as a whole or within each of strata. Furthermore, we did not appreciate a significant association between surgical approach and overall survival in the cohort as a whole or within each size strata.

CONCLUSION

In the National Cancer Database, patients undergoing MIA had similar positive surgical margins and overall survival compared with OA for masses ≤6 cm, 6.1 to 10cm, and >10 cm in size. Patients undergoing MIA should be carefully selected with surgical oncologic integrity being the primary determinants of surgical approach.

Radiotherapy for Pediatric Adrenocortical Carcinoma – Review of the Literature

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Radiotherapy (RT) is mostly performed for curative intent, only few cases in palliative setting are reported.

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The site of RT was predominantly tumor bed, abdominal cavity, and/or metastases.

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Adjuvant RT has to be discussed—even in the context of TPSs—especially for patients with high risk factors.

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Evidence regarding RT in in pediatric adrenocortical carcinoma is too limited to give any general recommendation. However, we suggest to consider adjuvant radiotherapy in individual patients with high risk of recurrence.

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A systematic international study with a common data platform is needed to establish evidence. on the role of RT in the treatment of children with adrenocortical carcinoma and to improve the outcome in this rare disease.

Background and purpose

Pediatric adrenocortical carcinoma (pACC) is a rare disease with poor prognosis. Publications on radiotherapy (RT) are scarce. This review summarizes the current data on RT for pACC and possibly provides first evidence to justify its use in this setting.

Materials and methods

We searched the PubMed and Embase database for manuscripts regarding RT for pACC.

Results

We included 17 manuscripts reporting on 76 patients treated with RT, after screening 2961 references and 269 full articles. In addition, we added data of 4 unreported pACC patients treated by co-authors. All reports based on retrospective data. Median age at first diagnosis was 11.1 years (70% female); 78% of patients presented with hormonal activity. RT was mostly performed for curative intent (78%). 88% of RT were administered during primary therapy. The site of RT was predominantly the local tumor bed (76%). Doses of RT ranged from 15 to 62 Gy (median 50 Gy). Information on target volumes or fractionation were lacking. Median follow-up was 6,9 years and 64% of the patients died of disease, with 33% alive without disease. In 16 of 48 patients with available follow-up data after adjuvant RT (33%) no recurrence was reported and in 3 of 9 patients palliative RT seemed to induce some benefit for the patient.

Conclusions

Our first systematic review on RT for pACC provides too few data for any general recommendation, but adjuvant RT in patients with high risk might be considered. International collaborative studies are urgently needed to establish better evidence on the role of RT in this rare malignancy.