Well-differentiated neuroendocrine tumor and osteoporosis: incidental findings?

The neuroendocrine tumors (NETs) have an increased incidence related to the age. Secondary osteoporosis might be found in patients with bone metastases and in those with NETs associated Cushing's disease or primary hyperparathyroidism. Primary osteoporosis might be found in postmenopausal women, but in case with non-metastatic NET as G1 NET it is difficult to establish the NET contribution to the bone loss. We present the case of a 53-year-old female accidentally diagnosed with G1 lung NET after surgery of the tumor. The immunohistochemistry pointed positive reaction for CHROMO, SYN and negative for CK7 and TTF1, and a Ki67 of 1-2% (well-differentiated neuroendocrine tumor). The central Dual X-Ray Absorptiometry (DXA) showed osteoporosis based on a T-score of -3. The patient had normal neuroendocrine markers and she was asymptomatic. She remained so for one year and the only therapy provided was weekly alendronate with adequate vitamin D and calcium supplements. Based on the pathological and immunohistochemistry profile, the low risk NET was diagnosed. We encourage the skeletal status assessment as central DXA in postmenopausal women with NETs, regardless clinical evidence of bone loss. The future will provide more epidemiological and pathogenic connections between the two dynamic fields of medicine as neuroendocrine tumors and osteoporosis.