Metastatic Pancreatic Neuroendocrine Tumor that Progressed to Ectopic Adrenocorticotropic Hormone (ACTH) Syndrome with Growth Hormone-releasing Hormone (GHRH) Production

Surgical Management of Pancreatic Neuroendocrine Tumors

Pancreatic neuroendocrine tumors (PNETs) are relatively uncommon malignancies, characterized as either functional or nonfunctional secondary to their secretion of biologically active hormones. A wide range of clinical behavior can be seen, with the primary prognostic indicator being tumor grade as defined by the Ki67 proliferation index and mitotic index. Surgery is the primary treatment modality for PNETs. While functional PNETs should undergo resection for symptom control as well as potential curative intent, nonfunctional PNETs are increasingly managed nonoperatively. There is increasing data to suggest small, nonfunctional PNETs (less than 2 cm) are appropriate follow with nonoperative active surveillance. Evidence supports surgical management of metastatic disease if possible, and occasionally even surgical management of the primary tumor in the setting of widespread metastases. In this review, we highlight the evolving surgical management of local and metastatic PNETs.

Growth hormone and gastrointestinal malignancy: An intriguing link

Growth hormone (GH) excess is associated with several systemic complications, one of which is the increased risk of neoplastic processes particularly of the gastrointestinal (GI) tract. Among the GI neoplasms, the most reported association is with benign and malignant neoplasms of the colon. In the majority of published literature, an increased incidence of GI neoplasms, both colonic adenomas as well as colorectal carcinoma is reported. However, the studies on colon cancer-specific mortality rate are conflicting with recent studies reporting similar cancer-specific mortality rates in comparison to controls. Many studies have reported an association of colorectal neoplasms with GH levels. Pathogenic mechanisms put forward to explain this association of GH excess and GI neoplasms primarily involve the increased GH-insulin-like growth factor 1 (IGF-1) signaling. Both GH and IGF-1 have proliferative, anti-apoptotic, and angiogenic effects on the systemic tissues leading to cellular proliferation. Other contributing factors to the increased risk of GI neoplasms include slow intestinal transit with a redundant large bowel, altered bile acids, deranged local immune response, shared genetic susceptibility factors and hyperinsulinemia. In view of the increased risk association, most guidelines for the care of acromegaly patients recommend an initial screening colonoscopy. Recommendations for further follow-up colonoscopy differ but broadly, the guidelines agree that it depends on the findings at first colonoscopy and state of remission of GH excess. Regarding the concern about the risk of colorectal cancers in patients receiving recombinant GH therapy, most cohort studies do not show an increased risk.

Ockham's Razor for a Retinal Lesion and Acromegaly and Breaking the Vicious Circle

Acromegaly due to ectopic secretion of growth hormone-releasing hormone (GHRH) is rare. Treatment consists of surgical removal of the primary tumor, cytostatic therapy, "cold" or radioactive somatostatin analogue treatment, and medical therapy for acromegaly, if needed. A 53 year-old female had an ocular lesion noted on a routine optician visit, originally considered to be an ocular melanoma. She had a bronchial carcinoid successfully removed 22 years previously. She had acromegalic features with an enlarged pituitary gland on magnetic resonance imaging and, additionally, metastatic lesions in her bones, liver, and thyroid gland. Elevated GHRH levels (>250× upper limit of normal) suggested a metastatic lung neuroendocrine tumor secreting GHRH. Cold and radioactive somatostatin analogue therapy reduced both GHRH and insulin-like growth factor 1 (IGF-1) levels, but normalization of the biochemical markers of acromegaly was only achieved after pegvisomant was introduced. Complete control of IGF-1 was achieved, and this may have hindered the growth of the metastatic lesions as well, as the patient remains well 13 years after the diagnosis of metastatic disease and 35 years after the original lung operation. A gradual rise in prolactin levels over last 4 years was noted, which is likely due to the prolonged effect of GHRH on prolactin-secreting cells. The diagnosis of this case applied the law of parsimony from the Ockham's razor principle. We consider that breaking the vicious circle of IGF-1 feeding the metastatic tumor was key for the long-term outcome of this case.

Somatostatin Treatment for Ectopic ACTH Syndrome due to Pancreatic Neuroendocrine Tumors: Review of the Literature

OBJECTIVES

To analyze and summarize the effect of SSA treatment on EAS due to p-NETs (EAS-p-NETs).

METHODS

Thirteen patients with EAS-p-NETs treated with SSAs at our center or described in the literature were included in this study. Clinical characteristics, laboratory data, imaging studies, histopathologic results, the effect of SSA treatment, and the prognosis of these EAS-p-NET patients were evaluated.

RESULTS

Four males and 9 females with an average age of 42.9 years were included in the study. The mean duration of follow-up was 38.8 ± 28.2 months. As one of the combined treatment measures, SSAs controlled the levels of ACTH and cortisol in 9 of the 13 patients (69.2%). Partial response was observed in 3 patients (23.1%), stable disease in 2 patients (15.4%), and progressive disease in 6 patients (46.2%). The median time to tumor progression was 24 months, and the median overall survival was 61 months. The side effects of SSA treatment included temporary mild abdominal pain, diarrhea, gallstones, and cholecystitis.

CONCLUSIONS

As a supplemental therapy, SSA treatment led to clinical and biochemical improvement with a good safety profile in patients exhibiting EAS-p-NET with metastasis. However, tumor progression was inhibited by SSA treatment in only a few patients. Combined with other treatments, SSAs may improve the prognosis of patients with EAS-p-NETs.

Primary hepatic neuroendocrine tumor associated with hypertension: A case report

Background

Primary neuroendocrine tumors are exceedingly rare and often misdiagnosed. The combined methods of ultrasonography, computed tomography ,and magnetic resonance imaging are typically applied. The diagnosis of the disease mainly depends on the histopathological examination. Surgical resection is the most effective treatment.

Case presentation

In the report, we describe the case of a patient with a primary hepatic neuroendocrine tumor (PHNET) associated with hypertension. The patient suffered from uncontrolled hypertension before the operation, and the blood pressure was not well controlled by oral antihypertensive drugs such as nifedipine, valsartan, and hydrochlorothiazide, but the patient's blood pressure completely returned to normal after the operation without drug control.

Conclusions

We encountered a rare case of a PHNET associated with hypertension via careful screening noticed by the patient at work; furthermore, we hope to collect more cases and find the relationship between neuroendocrine tumors and hypertension.

Acromegaly Caused by Ectopic Growth Hormone Releasing Hormone Secretion: A Review

INTRODUCTION

Ectopic acromegaly is a rare condition caused most frequently by growth hormone releasing hormone (GHRH) secretion from neuroendocrine tumors. The diagnosis is often difficult to establish as its main symptoms do not differ from those of acromegaly of pituitary origin.

OBJECTIVES

To determine most common clinical features and diagnostic challenges in ectopic acromegaly.

PATIENTS AND METHODS

A search for ectopic acromegaly cases available in literature was performed using PubMed, Cochrane, and MEDline database. In this article, 127 cases of ectopic acromegaly described after GHRH isolation in 1982 are comprehensively reviewed, along with a summary of current state of knowledge on its clinical features, diagnostic methods, and treatment modalities. The most important data were compiled and compared in the tables.

RESULTS

Neuroendocrine tumors were confirmed in 119 out of 121 patients with histopathological evaluation, mostly of lung and pancreatic origin. Clinical manifestation comprise symptoms associated with pituitary hyperplasia, such as headache or visual field disturbances, as well as typical signs of acromegaly. Other endocrinopathies may also be present depending on the tumor type. Definitive diagnosis of ectopic acromegaly requires confirmation of GHRH secretion from a tumor using either histopathological methods or GHRH plasma concentration assessment. Hormonal evaluation was available for 84 patients (66%) and histopathological confirmation for 99 cases (78%). Complete tumor resection was the main treatment method for most patients as it is a treatment of choice due to its highest effectiveness. When not feasible, somatostatin receptor ligands (SRL) therapy is the preferred treatment option. Prognosis is relatively favorable for neuroendocrine GHRH-secreting tumors with high survival rate.

CONCLUSION

Although ectopic acromegaly remains a rare disease, one should be aware of it as a possible differential diagnosis in patients presenting with additional symptoms or those not responding to classic treatment of acromegaly.

Pancreatic neuroendocrine neoplasms: Clinicopathological features and pathological staging

The nomenclature and classification of pancreatic neuroendocrine neoplasms has evolved in the last 15 years based on the advances in knowledge of the genomics, clinical behaviour and response to therapies. The current 2019 World Health Organization classification of pancreatic neuroendocrine neoplasms categorises them into three groups; pancreatic neuroendocrine tumours (PanNETs)(grade 1 grade 2, grade 3), pancreatic neuroendocrine carcinomas and mixed neuroendocrine-non-neuroendocrine neoplasms (MiNENs) based on the mitotic rate, Ki-67 index, morphological differentiation and/or co-existing tissue subtype. PanNETs are also classified into non-functional NET, insulinoma, gastrinoma, VIPoma, glucagonoma, somatostatinoma, ACTH-producing NET and serotonin producing NET based on hormone production and clinical manifestations. A portion of the cases were associated with genetic syndromes such as multiple neuroendocrine neoplasia 1 (MEN 1), neurofibromatosis and Von Hippel-Lindau syndrome. In view of the distinctive pathology and clinical behaviour of PanNENs, the current 8th AJCC/UICC staging system has separated prognostic staging grouping for PanNETs from the pancreatic neuroendocrine carcinomas or MiNENs. Pancreatic neuroendocrine carcinomas and MiNENs are staged according to the prognostic stage grouping for exocrine pancreatic carcinoma. The new stage grouping of PanNETs was validated to have survival curves separated between different prognostic groups. This refined histological and staging would lead to appropriate selections of treatment strategies for the patients with pancreatic neuroendocrine neoplasms.

Functional pancreatic neuroendocrine tumour causing Cushing's syndrome: the effect of chemotherapy on clinical symptoms

Background

Neuroendocrine tumours (NETs) are a heterogeneous group of diseases that can originate from any part of the gastrointestinal tract, bronchi, thyroid and pancreas. These tumours may be functioning or not depending on their ability to produce active substances, such as adrenocorticotrophic hormone (ACTH). ACTH-producing pancreatic neuroendocrine tumours are rare, with limited data about effective antitumor therapies.

Case Report

A 58-year-old man with a history of type-2 diabetes mellitus and arterial hypertension was diagnosed with Cushing’s syndrome (CS) secondary to an ACTH ectopic production from a well-differentiated neuroendocrine tumour of the pancreas metastatic to the liver. The patient underwent initial body-caudal pancreatectomy, splenectomy and hepatic nodulectomy with subsequent recurrence. Hepatic embolisation and somatostatin analogues were used to control CS but without success. Bilateral adrenalectomy led to CS control, while capecitabine and oxaliplatin (CAPOX) was effective in controlling tumour growth and ACTH production.

Discussion

ACTH-producing pancreatic neuroendocrine tumours are rare, aggressive and difficult to treat with available therapies. In settings of limited resources, such as in developing countries where targeted therapies are not available, cytotoxic chemotherapy with CAPOX represents a good and inexpensive option to control ACTH-producing pancreatic neuroendocrine tumours. Because of its complexity, the management of this tumour should be performed by multidisciplinary teams.