Neuroendocrine gastro-enteropancreatic tumors - from eminence based to evidence-based medicine - A Scandinavian view

Neuroendocrine tumors (NETs) comprise a heterogenous group of neoplasms with variable clinical expression and progression. The primary tumors most frequently occur in the lungs, intestine and the pancreas. The NET incidence is approximately 6.1/100,000 per year with a prevalence higher than 35/100,000 per year. A NET may be functioning with symptoms related to hormone overproduction or non-functioning, not presenting any hormone-related symptoms. From the early 1980s and onwards, Uppsala University Hospital has contributed significantly to diagnosis, just to mention immunohistochemistry, radio-immunoassays for hormones and peptides and molecular imaging. On the therapeutic side, treatments with cytotoxics as well as biologicals such as, somatostatin analogs and interferons have been evaluated. We have furthermore been involved in important phase III trials for registration of so called, new targeted agents such as, RADIANT-3 and RADIANT-2. Our group were also the first to localize the gene for MEN I on chromosome 11 locus q13. Most recent developments have been the establishments of new biomarkers such as, olfactory receptor E51E1 as well as micro-RNAs in carcinoid tumors of the intestine and lung. A new oncolytic virus, Ad-Vince, for treatment of most NETs has been developed and is ready for the clinic. Furthermore, we have been involved in establishing Nordic and international collaborations. Today, NETs is an area with rapid development and recognized by international organizations at conferences, with large attendance. The Nordic countries continue to be significant contributors to the field.

Endocrine tumors of the pancreas: Ki-67 immunoreactivity on paraffin sections is an independent predictor for malignancy: a comparative study with proliferating-cell nuclear antigen and progesterone receptor protein immunostaining, mitotic index, and other clinicopathologic variables

Prediction for malignancy of pancreatic endocrine tumors (PET) is often a formidable challenge for the pathologist. The authors evaluated the role of the proliferative activity and progesterone receptor protein (PgRP) in predicting prognosis and survival of PET. Twenty-three functioning (FT) and 31 nonfunctioning tumors (NFT) were evaluated for mitotic activity and immunostaining for Ki-67 antigen, proliferating cell nuclear antigen (PCNA), and progesterone receptor protein (PgRP) on paraffin sections. The results were expressed as a percentage (index) of immunoreactive or mitosing cells. All 54 cases showed immunostaining for Ki-67 and PCNA, and valuable mitotic index, whereas only a fraction of tumors (25 of 54 cases) exhibited PgRP expression. Ki-67 and PCNA indexes correlated strongly between themselves and to mitotic index, whereas an inverse relationship was observed between cell proliferation and PgRP status in both FT and NFT. Although univariate analysis showed that Ki-67, PCNA, mitotic and PgRP indexes, stage, immunoreactivity for hormones other than insulin, diameter, and nonfunctioning type of tumor were statistically correlated to survival, Cox's regression method let only Ki-67 index emerge as an independent predictor of survival using a cutoff value of 5% in both FT and NFT.

A serotonin and beta HCG-producing islet cell carcinoma associated with focal nodular hyperplasia of the liver

A 48-year-old woman is described with a pancreatic islet cell carcinoma that had no clinical evidence of hormone production. This neoplasm was removed by radical distal pancreatectomy. Immunohistochemical and extraction studies performed on the tumor tissue revealed that it was producing serotonin and beta HCG. Circulating levels of these hormones were elevated in preoperative serum samples that had been frozen. Beta HCG, a known tumor marker, has remained normal following operation, and this mirrors her clinical course since she has no evidence of disease 1.5 yr after operation. This patient also had focal nodular hyperplasia of the liver. It is possible that the trophoblastic hormone, beta HCG, which was being produced in excess by the islet tumor, may have directly or indirectly caused or facilitated the development of focal nodular hyperplasia.