Malignant islet‐cell tumors of the pancreas

Abstract

Although malignant islet‐cell tumors are uncommon, they are an important group of pancreatic neoplasms because appropriate treatment can often result in effective palliation even though cure is infrequent. In general, these tumors are relatively slow growing so that a combination of surgical and chemotherapeutic measures may prove very beneficial. In some patients with tumors hypersecreting insulin, gastrin, glucagon, or vasoactive intestinal polypeptide (VIP), the hormonal effects of the neoplasm can be life‐threatening. Surgical treatment must, therefore, consider both the functional and malignant characteristics of the individual tumor. In many patients with functional tumors, surgical debulking of the primary tumor may be indicated even when a curative resection cannot be accomplished. Some malignancies may be cured by an appropriate pancreatic resection even when peripancreatic lymph nodes are already involved. Although a Whipple procedure is not indicated when hepatic metastases are present, this procedure may cure tumors localized to the pancreatic head and/or peripancreatic lymph nodes. Because hepatic metastases are usually multiple and involve both lobes, liver resections, other than wedge excisions of peripherally located functional metastases, are not indicated. Malignant nonfunctioning islet‐cell tumors are probably best treated with systemic or regional chemotherapy when metastatic. Surgical resections or bypass procedures may be infrequently useful in those cases in which the primary tumor causes either duodenal or bile duct obstruction. The most effective methods used to control hepatic metastases are systemic and hepatic arterial chemotherapy. An alternative is selective hepatic artery embolization. Recently, an implantable hepatic arterial infusion pump has been used with encouraging results in this group of patients. The chemotherapeutic agents that have been most effective in the treatment of hepatic metastases include streptozotocin, DTIC, and fluorouracil.

Experiences with Nonfunctioning Neuroendocrine Neoplasms of the Pancreas

“…In addition, another patient with a curatively resected primary tumor of the pancreas who developed metastases received transcatheter hepatic arterial chemoinfusion for multiple liver metastases and radiation therapy for bone metastases and is still alive >35 months after the diagnosis. Although several studies [2, 9, 17, 18] have indicated a role for adjuvant chemoradiation therapy, our results could not confirm any benefits. However, considering few cases with positive results after adjuvant chemoradiation therapy, we believe that curative resection of primary tumors of the pancreas should be attempted first, and adjuvant therapy may be given to those who have palliative resection of the tumors.…”

Role of Chemoembolization in Synchronous Liver Metastases from Pancreatic Endocrine Tumours

“…Pancreatic endocrine tumours, particularly those of nonfunctioning type, are diagnosed in more than a quarter of the cases when liver metastases are already present [14, 15]. This figure is confirmed by our own experience, in which 28 patients out of 80 (35%) reached the diagnosis with synchronous metastases.…”

“…The nonfunctioning forms, on the other hand, are detected later as a result of symptoms related to the presence of a mass [12]. For this reason, at the time of diagnosis they appear generally larger than the former [12, 13]and often present liver metastases [14, 15]. The particular biological behavior of these tumours, characterized by a long natural history, even in the presence of liver metastases, has important therapeutic implications [1, 16, 17, 18].…”

Spezielle diagnostische und therapeutische Aspekte beim Insulinom

“…Bei diffuser Metastasierung ist die Indikation relativ und orientiert sich an Risiko und klinischer Symptomatik. Ein Debulking mit Tumorreduktion und atypischer Entfernung von großen Metastasen kann eine gute Palliation mit Beherrschung der Symptomatik darstellen [7,12,22]. Die Indikation ist kritisch und am Einzelfall orientiert zu stellen, da konservative Verfahren wie Somatostatinanaloga, Embolisation und Chemotherapie effektive Alternativen sind.…”