Table 1 Summary of Patient History

2013

Whipple’s triad, weight gain

• Serum glucose 49 mg/dL (normal range: 70–99 mg/dL), serum insulin 8.1 μIU/mL (normal range: 2.6–24.9 μIU/mL), C-peptide 2.2 ng/mL (normal range: 1.1–4.4 ng/mL)

• 72-hour fast: hyperinsulinemic hypoglycemia

• Abdominal CT with intravenous contrast: 1.1 × 1.6 × 2 cm hypervascular mass in the second portion of the duodenum; normal pancreas.

• OctreoScan: no uptake in the area of the mass.

• EGD: mass in the duodenal sweep

• EUS: 1.6 cm × 1.6 cm duodenal mass; 3 lymph nodes up to 1 cm in length.

Exploratory laparotomy with duodenotomy and NET enucleation

2015

Hypoglycemia during exercise

• Random glucose 60–70 mg/dL during episodes

• 7-day CGM negative for hypoglycemia

Abdominal CT with IV contrast: no recurrence

2017–2018

Increased frequency of recurrent hypoglycemia

7-day CGM with 29% nocturnal hypoglycemia

• Abdominal CT with IV contrast: no recurrence

• PET-CT with Ga68-DOTATATE: 1.5 cm × 1.3 cm soft tissue nodule adjacent to inferior pancreatic head and wall of the 2nd portion of the duodenum, maximum SUV 41

• EUS: peripancreatic lymphadenopathy; normal duodenum and pancreas

• Lymph node fine-needle aspiration: confirmed NET

• Exploratory laparotomy: 5/12 lymph nodes with well-differentiated NET

• Hypoglycemia resolved after surgery

2020

Feeling well

14-day CGM: 99% time in range, < 1% time below range

Ga68-DOTATATE scan: small focus of uptake at the root of mesentery (possible overcall)

• Diagnostic CGM every 3 months

2021

Feeling well

14-day CGM: 98% time in range, < 1% time below range

Ga68-DOTATATE scan: no focal uptake