Utilising combined treatment modalities in non-islet cell tumour hypoglycaemia (NICTH)

Rochan Agha-Jaffar; Rebecca Scott; Si Chong Lok; Mark Cohen

Non-islet cell tumour hypoglycaemia (NICTH) is a rare paraneoplastic phenomenon and there is limited guidance regarding different treatment modalities.

We present two cases of NICTH focusing on the combined methods used to control hypoglycaemia.

The first involves an 89-year-old gentleman diagnosed with a pelvic leiomyoma in 2003. For several years, he had experienced recurrent collapses which briefly improved following tumour embolisation in 2007. The cause of these collapses eluded diagnosis until 2009, when, during one episode, hypoglycaemia in the absence of ketonuria was noted. Our second case is a 63-year-old gentleman, who was diagnosed with a metastatic gastrointestinal stromal tumour (GIST) in 2007 (CD117, CD34 positive, KIT exon 9 gene mutation) and had been commenced on sunitinib. He presented with hypoglycaemia 18 months later.

During hypoglycaemia (plasma glucose 2.2 in both patients) undetectable serum insulin and C-peptide levels were demonstrated. IGFBP3 values were normal. Further results are tabulated below:

Table 1
	Pre-treatment			Post-treatment
	IGF1 (ref range 6–36 nmol/l)	IGF2 (ref range 6–36 nmol/l)	IGF2/IGF1 ratio (ref range <10)	IGF1 (ref range 6–36 nmol/l)	IGF (ref range 6–36 nmol/l)	IGF2/IGF1 ratio (ref range <10)
Case 1	5.5	109.2	19.9	16.1	57.0	3.5
Case 2	3.4	97.6	28.7	19.1	102.3	5.4

Table 1
	Pre-treatment			Post-treatment
	IGF1 (ref range 6–36 nmol/l)	IGF2 (ref range 6–36 nmol/l)	IGF2/IGF1 ratio (ref range <10)	IGF1 (ref range 6–36 nmol/l)	IGF (ref range 6–36 nmol/l)	IGF2/IGF1 ratio (ref range <10)
Case 1	5.5	109.2	19.9	16.1	57.0	3.5
Case 2	3.4	97.6	28.7	19.1	102.3	5.4

Treatment with dexamethasone (2 mg BD and 8 mg BD respectively) and recombinant GH (35 μg/kg daily) was initiated in both cases. Octreotide scans did not demonstrate increased uptake in either tumour. Despite re-embolisation of the leiomyoma, case 1 remains GH and steroid dependent.

Combined therapy with glucocorticoids and recombinant GH in these two cases has effectively controlled NICTH.

Endocrine Abstracts

P101