Revisiting the usefulness of the short acute octreotide test to predict treatment outcomes in acromegaly

Introduction

We previously described that a short version of the acute octreotide test (sAOT) can predict the response to first-generation somatostatin receptor ligands (SRLs) in patients with acromegaly. We have prospectively reassessed the sAOT in patients from the ACROFAST study using current ultra-sensitive GH assays. We also studied the correlation of sAOT with tumor expression of E-cadherin and somatostatin receptor 2 (SSTR2) .

Methods

A total of 47 patients treated with SRLs for 6 months were evaluated with the sAOT at diagnosis and correlated with SRLs' response. Those patients whose IGF1 decreased to <3SDS from normal value were considered responders and those whose IGF1 was ≥3SDS, were considered non-responders. The 2 hours GH value (GH2h) after s.c. administration of 100 mcg of octreotide was used to define predictive cutoffs. E-cadherin and SSTR2 immunostaining in somatotropinoma tissue were investigated in 24/47 and 18/47 patients, respectively.

Results

In all, 30 patients were responders and 17 were non-responders. GH2h was 0.68 (0.25-1.98) ng/mL in responders vs 2.35 (1.59-9.37) ng/mL in non-responders (p<0.001). GH2h = 1.4ng/mL showed the highest ability to identify responders (accuracy of 81%, sensitivity of 73.3%, and specificity of 94.1%). GH2h = 4.3ng/mL was the best cutoff for non-response prediction (accuracy of 74%, sensitivity of 35.3%, and specificity of 96.7%). Patients with E-cadherin-positive tumors showed a lower GH2h than those with E-cadherin-negative tumors [0.9 (0.3-2.1) vs 3.3 (1.5-12.1) ng/mL; p<0.01], and patients with positive E-cadherin presented a higher score of SSTR2 (7.5 ± 4.2 vs 3.3 ± 2.1; p=0.01).

Conclusion

The sAOT is a good predictor tool for assessing response to SRLs and correlates with tumor E-cadherin and SSTR2 expression. Thus, it can be useful in clinical practice for therapeutic decision-making in patients with acromegaly.

Efficacy and safety of temozolomide in the treatment of aggressive pituitary neuroendocrine tumours in Spain

Current guidelines recommend temozolomide as the first-line chemotherapy for aggressive pituitary neuroendocrine tumours. However, no clinical trials have been conducted to date and clinical experience is quite limited. We retrospectively analyzed 28 patients (9 women and 19 men), aged 46.6 + 16.9, with aggressive pituitary tumours (4 pituitary carcinomas and 24 aggressive adenomas) treated with temozolomide in 10 Spanish pituitary reference centres. Four patients had Cushing's disease, 9 prolactinomas and 15 clinically non-functioning pituitary tumours (seven silent corticotroph, three silent somatotroph, one silent lactotroph, one silent gondotroph and three null-cell tumours). Median size at diagnosis was 10.5 cm3 (IQR 4.7-22.5), with cavernous sinus invasion in 88% and no metastases. Pre-temozolomide treatment, these data were 5.2 cm3 (IQR 1.9-12.3), 89.3% and 14.3% (2 intracranial and 2 spinal metastases). All patients had undergone surgery (1-5 surgeries), 25 (89.3%) had received radiotherapy (7 of them reirradiated) and 13(46.4%) had received cabergoline. One patient interrupted temozolomide prematurely. The remaining 27 patients received a median of 13 cycles (range 3-66) of 5 days every 28 days, with a mean initial dose of 265 ± 73 mg when administered alone and of 133 ± 15 mg when co-administered with radiotherapy. Eight patients (29.6%) had a significant reduction (>30%) in tumour volume and 14 (51.9%) attained tumour stabilization. After a median follow-up of 29 months (IQR 10-55), 8 out of these 22 showed disease progression. A longer progression-free survival was found in the five patients who received concomitant radiotherapy. Seven patients (25%) died (all of them because of tumour progression or complications of treatments) at 77 months (IQR 42-136) after diagnosis and 29 months (IQR 16-55) after the first dose of temozolomide. Adverse effects occurred in 18 patients (14 mild and 4 moderate or severe). In conclusion, temozolomide is an effective medical treatment for aggressive pitNET and pituitary carcinomas but is sometimes followed by tumour progression. Co-administration with radiotherapy may increase progression-free survival.

Autonomous cortisol secretion in patients with primary aldosteronism: prevalence and implications on cardiometabolic profile and on surgical outcomes

Purpose

The aim of this study was to evaluate the prevalence of autonomous cortisol secretion (ACS) in patients with primary aldosteronism (PA) and its implications on cardiometabolic and surgical outcomes.

Methods

This is a retrospective multicenter study of PA patients who underwent 1 mg dexamethasone-suppression test (DST) during diagnostic workup in 21 Spanish tertiary hospitals. ACS was defined as a cortisol post-DST >1.8 µg/dL (confirmed ACS if >5 µg/dL and possible ACS if 1.8-5 µg/dL) in the absence of specific clinical features of hypercortisolism. The cardiometabolic profile was compared with a control group with ACS without PA (ACS group) matched for age and DST levels.

Results

The prevalence of ACS in the global cohort of patients with PA (n = 176) was 29% (ACS-PA; n = 51). Ten patients had confirmed ACS and 41 possible ACS. The cardiometabolic profile of ACS-PA and PA-only patients was similar, except for older age and larger tumor size of the adrenal lesion in the ACS-PA group. When comparing the ACS-PA group (n = 51) and the ACS group (n = 78), the prevalence of hypertension (OR 7.7 (2.64-22.32)) and cardiovascular events (OR 5.0 (2.29-11.07)) was higher in ACS-PA patients than in ACS patients. The coexistence of ACS in patients with PA did not affect the surgical outcomes, the proportion of biochemical cure and clinical cure being similar between ACS-PA and PA-only groups.

Conclusion

Co-secretion of cortisol and aldosterone affects almost one-third of patients with PA. Its occurrence is more frequent in patients with larger tumors and advanced age. However, the cardiometabolic and surgical outcomes of patients with ACS-PA and PA-only are similar.

Differences in the presentation and evolution of primary aldosteronism in elderly (≥65 years) and young patients (<65 years)

OBJECTIVE

To compare the presentation and evolution of primary aldosteronism (PA) in the elderly (≥65 years) and young patients (<65 years).

METHODS

A retrospective multicenter study was performed in 20 Spanish hospitals of PA patients in follow-up between 2018 and 2021.

RESULTS

Three hundred fifty-two patients with PA <65 years and 88 patients ≥65 years were included. Older PA patients had a two-fold higher prevalence of type 2 diabetes, dyslipidemia, and cerebrovascular disease, but these differences disappeared after adjusting for hypertension duration. At diagnosis, diastolic blood pressure was lower than in young patients (83.3 ± 11.54 vs 91.6 ± 14.46 mmHg, P < 0.0001). No differences in the rate of overall correct cannulation (56.5% vs 42.3%, P = 0.206) or the diagnosis of unilaterality (76.9% vs 62.5%, P = 0.325) in the adrenal venous sampling (AVS) was observed between the elderly and young groups. However, there was a lower proportion of PA patients who underwent adrenalectomy in the elderly group than in the younger group (22.7% (n = 20) vs 37.5% (n = 132), P = 0.009). Nevertheless, no differences in the rate of postsurgical biochemical (100% (n = 14) vs 92.8% (n = 90), P = 0.299) and hypertension cure (38.6% (n = 51) vs 25.0% (n = 5), P = 0.239) were observed between both groups.

CONCLUSION

Older patients with PA have a worse cardiometabolic profile than young patients with PA that it is related to a longer duration of hypertension. However, the results of the AVS, and adrenalectomy are similar in both groups. Therefore, the management of elderly patients with PA should be based not only on age, but rather on the overall medical, physical, social, and mental characteristics of the patients.

Analysis of expression of the PD-1/PD-L1 immune checkpoint system and its prognostic impact in gastroenteropancreatic neuroendocrine tumors

The immune checkpoint based therapy targeting the programmed death-1 (PD-1) receptor and its PD-L1 ligand has recently been approved for the therapy of different malignant conditions, but not yet for gastroenteropancreatic neuroendocrine tumors (GEP-NETs). In this context, we evaluated the expression of PD-1 and PD-L1 in GEP-NETs and its potential correlations with clinical outcomes. Expression of PD-1/PD-L1 was analyzed by immunohistochemistry in 116 GEP-NETs and 48 samples of peritumoral tissue. In addition, the expression of these molecules was assessed by flow cytometry in peripheral blood mononuclear cells (PBMC) from patients with GEP-NETs (n = 32) and healthy controls (n = 32) and in intratumoral mononuclear cells (TMCs) (n = 3). Expression of PD-L1 and PD-1 was detected by immunohistochemistry in 6% and 1% of tumor tissue samples, respectively, and in 8% of peritumoral tissue samples, for both markers. We also observed that PD-1 expression by TMCs was associated with metastatic disease at diagnosis, and the levels of circulating PD-1+ PBMCs were associated with progressive disease upon follow-ups. In addition, circulating PD-1+ PBMCs were significantly correlated with PD-L1 expression by tumor cells. Our data suggest that PD-1/PD-L1 is expressed in 1 to 8% of GEP-NETs, and that this feature is significantly associated with disease evolution (p < 0.01).