RESUMO
Insulinoma is a functional pancreatic neuroendocrine tumor (pNET). Usually benign and solitary, these tumors present with recurrent episodes of hypoglycemia due to insulin hypersecretion. It's a rare cause of post bariatric surgery hypoglycemia and hence poses a diagnostic challenge. Here, we report the first case of a 53-year-old male with insulinoma unmasked post sleeve gastrectomy with incidental renal cell carcinoma (RCC). He presented with symptoms of Whipple's triad after two months of sleeve gastrectomy done for morbid obesity. On further inquiry, the patient gave a history of an asymptomatic peripancreatic neuroendocrine tumor (NET) for the past 11 years. With a suspicion of insulinoma, biochemical workup followed by non-invasive imaging like GA-68 DOTA and CT triphasic abdomen scan was done to guide the diagnosis of an insulinoma which also detected a second primary tumor in the right kidney, likely to be a malignant RCC. Following pancreatic mass excision with radical nephrectomy for right renal mass, histopathology (HPE) and immunohistochemistry (IHC) confirmed the diagnosis of an insulinoma and a right renal clear cell carcinoma. The patient was discharged with no further episodes of hypoglycemia. Hence, persistent hypoglycemia post bariatric surgery could be an indication of a hidden insulinoma and this possibility of synchronous tumors should be kept in mind when dealing with rare tumors like insulinoma.
RESUMO
BACKGROUND: Therapeutic decisions in breast carcinoma are being made on the basis of tumor cell proliferation using exorbitant genomic tests. The 2013 St Gallen meeting advocated surrogate definitions for classifying tumors into luminal subtypes on the basis of immunohistochemical (IHC) markers. We studied the classification of estrogen receptor (ER)-positive tumors using these definitions as well as different methods for Ki-67 labeling index (LI) estimation. PATIENTS AND METHODS: A total of 541 ER+ invasive breast carcinoma cases from January 2012 to December 2012 were evaluated for Ki-67 LI by the average and hot spot methods. The IHC results of ER, PR, and human epidermal growth factor receptor 2 (HER2) were noted. HER2 IHC equivocal (2+) samples were subjected to HER2 fluorescence in-situ hybridization testing. Luminal subgroups created on the basis of the 2013 St Gallen meeting guidelines were correlated with clinicopathologic variables and disease-free survival. RESULTS: The distribution of luminal subtypes was as follows: luminal A-like, 13.3%; luminal B-like (HER2-), 57.9%; and luminal B-like (HER2+), 28.8%. Approximately 6% of cases were recategorized into different subgroups when the average method was used instead of the hot spot method for Ki-67 LI assessment. Younger patients (≤ 50 years), grade 3 tumors, positive axillary nodes, recurrence, and distant metastasis had a positive statistical correlation with luminal B-like (HER2-) subtype. Patients with luminal B-like (HER2-) tumors had a shorter disease-free survival compared to patients with luminal A-like tumors. CONCLUSION: Ki-67 LI, irrespective of the method of assessment, along with PR, can be efficiently used to divide ER+ tumors into prognostic subgroups in Indian patients.
