Severe hypoglycemia with "Big"-IGF-2 oversecretion by a giant phyllode tumor of the breast: a rare case of non-islet cell tumor-induced hypoglycemia (NICTH)

Non-Islet-Cell Tumor Hypoglycemia Secondary to Malignant Phyllodes Tumor of the Breast

Background/Objective

Non-islet cell tumor hypoglycemia (NICTH) is an uncommon condition, of which only a few cases caused by malignant phyllodes tumor of the breast have been reported. We describe a case of NICTH secondary to malignant phyllodes tumor with good response to glucocorticoid therapy.

Case Report

A 62-year-old woman with a rapidly enlarging left breast mass presented with drowsiness and a capillary blood glucose level of 32.4 mg/dL. Her plasma glucose and insulin levels were 36.0 mg/dL (reference range, 72-144 mg/dL) and 0.6 mIU/L (reference range, 0.0-25.0 mIU/L), respectively. Her beta-hydroxybutyrate and c-peptide levels were undetectable. The insulin-like growth factor (IGF)-I and IGF-II levels were 37 μg/L (reference range, 43-220 μg/L) and 1062 ng/mL (reference range, 333-967 ng/mL), respectively, with an IGF-II:IGF-I molar ratio of 29.4. Prednisolone 30 mg per day was initiated with improvement in hypoglycemia. Outpatient flash glucose monitoring profile was stable with mild hypoglycemia (glucose level, 54-68.5 mg/dL) detected 5% of the time. The patient underwent left mastectomy with axillary clearance 4 weeks later. Histology was reported as malignant phyllodes tumor with extensive ductal carcinoma in situ. Prednisolone was stopped after surgery. The patient was treated with letrozole and adjuvant radiotherapy. There was no recurrence of hypoglycemia during the subsequent 24-month follow-up.

Discussion

The mainstay of treatment for NICTH is surgical resection of the culprit tumor. Although glucocorticoid treatment has also been widely used for NICTH, few reports have demonstrated efficacy for NICTH secondary to phyllodes tumor.

Conclusion

We report a rare case of malignant phyllodes tumor of the breast resulting in NICTH and demonstrated good response to glucocorticoids as a bridge to definitive surgery.

A systematic review of literature on Insulin-like growth factor-2-mediated hypoglycaemia in non-islet cell tumours

INTRODUCTION

Insulin-like growth factor-2 (IGF-2)-mediated hypoglycemia is a rare yet clinically significant entity with considerable morbidity and mortality. Existing literature is limited and fails to offer a comprehensive understanding of its clinical trajectory, management and prognostication.

METHODS

Systematic review of English-language articles reporting primary patient data on IMH was searched using electronic databases (PubMed, Scopus and Embase) from any date up to 21 December 2022. Data were analysed in STATA-16.

RESULTS

The systematic review contains 172 studies, including 1 Randomised controlled trial, 1 prospective observational study, 5 retrospective observational studies, 150 case reports, 11 case series and 4 conference abstracts. A total of 233 patients were analysed, averaging 60.6 ± 17.1 years in age, with comparable proportions of males and females. The commonest tumours associated with Insulin-like Growth Factor-2-mediated hypoglycaemia were fibrous tumours (N = 124, 53.2%), followed by non-fibrous tumours originating from the liver (N = 21, 9%), hemangiopericytomas (N = 20, 8.5%) and mesotheliomas (N = 11, 4.7%). Hypoglycaemia was the presenting feature of NICT in 42% of cases. Predominant clinical features included loss of consciousness (26.7%) and confusion (21%). The mean IGF-2 and IGF-1 levels were 882.3 ± 630.6 ng/dL and 41.8 ± 47.8, respectively, with no significant correlation between these levels and patient outcomes. Surgical removal was the most employed treatment modality (47.2%), followed by medication therapy. The recovery rate was 77%, with chronic liver disease (CLD) significantly associated with a poor outcome (OR: 7.23, P: 0.03). Tumours originating from fibrous tissues were significantly associated with recovery (p < .001). In the logistic regression model, CLD remained a significant predictor of poor outcomes.

CONCLUSION

This systematic review highlights that most non-islet-cell tumour-hypoglycaemia (NICTH) is due to fibrous tumours. NICTs demonstrate a variable prognosis, which is fair if originating from fibrous tissue. Management such as octreotide, corticosteroids, diazoxide, embolization, radiotherapy and surgical resection have disparate success rates.

Severe Hypoglycemia Caused by a Giant Borderline Phyllodes Tumor of the Breast: A Case Report and Literature Review

A case of hypoglycemic coma caused by a giant borderline phyllodes tumor of the breast has been described. The patient, a 63-year-old woman, was admitted with recurrent unconsciousness. She had a giant breast tumor with decreased blood glucose, insulin, and C-peptide. The patient's hypoglycemia resolved rapidly after resection of the breast tumor. Pathological examination indicated a borderline phyllodes tumor of the breast, and immunohistochemistry suggested high expression of insulin-like growth factor-2 (IGF-2) in the tumor tissue. A literature review is also included to summarize the clinical characteristics of such patients and to serve as a unique resource for clinical diagnosis and treatment of similar cases.

Recurrent Severe Hypoglycemia Secondary to Benign Phyllodes Tumor of the Breast: A Rare Case of Non-Islet Cell Tumor-induced Hypoglycemia (NICTH)

Non-islet cell tumor-induced hypoglycemia (NICTH) secondary to phyllodes tumor is extremely rare but potentially life threatening if not treated promptly. We report a case of a 46-year-old Indian female without underlying diabetes mellitus who presented with a large breast tumor and recurrent severe symptomatic hypoglycemia. Investigations supported the diagnosis of NICTH. The hypoglycemia only resolved after corticosteroids and mastectomy. This case highlights the importance of considering NICTH in the evaluation of patients with voluminous tumor and hypoglycemia.

A Giant Borderline Phyllodes Tumor of Breast With Skin Ulceration Leading to Non-Insular Tumorigenic Hypoglycemia: A Case Report and Literature Review

Phyllodes tumor (PT) is a special type of breast tumors, including three types: malignant, borderline, and benign. Most of these tumors form unilateral disease and can rapidly increase in size. The occurrence of axillary lymph node metastasis is rare. Tumor-associated hypoglycemia can be divided into non-islet cell tumor and insulinoma. In non-islet cell tumor hypoglycemia (NICTH), a considerable high molecular weight form of insulin like growth factor 2 (IGF-2) is formed, which abnormally binds to insulin receptors in the tissues and causes hypoglycemia. Breast phyllodes tumors with NICTH are rare and first reported in 1983. Surgical resection is the main treatment and hypoglycemia symptoms usually resolve after surgery. Nevertheless, prior to surgery, intravenous glucose infusion is used to maintain blood glucose levels. A female patient presented with a rapidly growing breast mass and was diagnosed with a phyllodes tumor with NICTH at our hospital in August 2020; she was successfully treated through surgical resection. We reviewed the relevant literature to investigate and analyze the relationship between NICTH and phyllodes tumors, as well as optimize its diagnosis and treatment.

Malignant phyllodes tumor of the breast presenting with hypoglycemia: a case report and literature review

Phyllodes tumors are rare fibroepithelial neoplasms that account for less than 1% of all breast tumors and are typically found in middle-aged women. Phyllodes tumors that present with hypoglycemia are even rarer. No one morphologic finding is reliable in predicting the clinical behavior of this tumor. Surgery has been the primary mode of treatment to date. However, the extent of resection and the role of adjuvant radiotherapy or chemotherapy are still controversial. Here, we present a challenging case of malignant phyllodes tumor of the breast associated with hypoglycemia, and review the literature regarding clinical findings, pathologic risk factors for recurrence, and treatment recommendations.

Hypoglycemia mediated by paraneoplastic production of Insulin like growth factor-2 from a malignant renal solitary fibrous tumor - clinical case and literature review

BACKGROUND

Hypoglycemic episodes are infrequent in individuals without a history of diabetes mellitus or bariatric surgery. When hypoglycemia does occur in such individuals, an uncommon but important diagnosis to consider is non-islet cell tumor hypoglycemia (NICTH). We report a case of NICTH associated with paraneoplastic insulin-like growth factor-2 (IGF-2) production and review current relevant medical literature.

CASE PRESENTATION

A 60 year old male with no relevant past medical history was referred to the endocrinology clinic with 18 month history of episodic hypoglycemic symptoms and, on one occasion was noted to have a fingerstick glucose of 36 mg/dL while having symptoms of hypoglycemia. Basic laboratory evaluation was unrevealing. Further evaluation however showed an elevated serum IGF-2 level at 2215 ng/mL (reference range 411-1248 ng/mL). Imaging demonstrated a large right suprarenal mass. A right nephrectomy with resection of the mass demonstrated a malignant solitary fibrous tumor. Post resection, the patient's IGF-2 levels normalized and hypoglycemic symptoms resolved.

CONCLUSION

Due to the structural and biochemical homology between IGF-2 and insulin, elevated levels of IGF-2 can result in hypoglycemia. A posttranslational precursor to IGF-2 known as "big IGF" also possesses biologic activity. Review of recent reported cases of NICTH identified widespread anatomic locations and varied pathologic diagnoses of tumors associated with paraneoplastic production of IGF-2 causing hypoglycemia. Definitive management of hypoglycemia associated with paraneoplastic production of IGF-2 consists of resection of the tumor responsible for IGF-2 production. Accumulating literature provides a firm basis for routine IGF-2 laboratory evaluation in patients presenting with spontaneous hypoglycemia with no readily apparent cause.

IGF-II Producing Hepatocellular Carcinoma Treated with Sorafenib: Metabolic Complications and a Foresight to Molecular Targeting Therapy to the IGF Signal

Hypoglycemia is a rare paraneoplastic manifestation of patients with neoplasms. Hypoglycemia can be induced by several causes, including an aberrant increase of hypoglycemic agents and adrenal insufficiency. Sorafenib is the first agent to demonstrate a survival benefit in the treatment of advanced hepatocellular carcinoma (HCC). This small molecule inhibits serine/threonine kinase RAF in tumor cells and tyrosine kinases VEGFR/PDGFR in tumor vasculature and decreases tumor growth and angiogenesis. In this paper, we report a case of HCC who was treated with sorafenib and showed severe hypoglycemia. This hypoglycemia might be induced by two causes, both adrenal insufficiency as an adverse effect of sorafenib and activation of the insulin-like growth factor (IGF) signal by excessive secretion of incompletely processed precursors of IGF-II. Although the IGF signal is suggested to be involved in aberrant growth of HCC in some cases, there is no other report showing the influence of sorafenib on HCC with active IGF signal. Unfortunately, the effect of sorafenib was limited in the present case. However, emerging drugs that directly inhibit the IGF signal can be expected to be highly effective in the treatment of HCC with hypoglycemia.