Detailed Abstract
[E-poster - Biliary & Pancreas (Pancreas Disease/Surgery)]
[EP 156] Rare Double Primary Malignancies: Pancreatic GIST Mimicking As Metastatic Lesion Of Myoepithelial Carcinoma Of Salivary Gland - A Case Report
Vania Myralda MARBUN*1 , Indah JAMTANI1
1 Surgery, Cipto Mangunkusumo Hospital - Universitas Indonesia, INDONESIA
Background : A pancreatic gastrointestinal stromal tumor (PGIST) is an extremely rare case which was less than 5% of extra-gastrointestinal stromal tumors (EGIST) and less than 1% of all malignant pancreatic tumors.When a pancreatic lesion exists synchronously or metachronously with another organ’s primary tumor, metastasis to the pancreas, which occurs only in 2% of all organ metastases, can be first regarded followed by other types of primary tumors such as neuroendocrine and gastrointestinal stromal tumors (GIST).
Methods : We report a case of double primary of synchronous malignancy of MCSG and PGIST with physical examination, radiological documentation, and specimen.
Results : This report describes the occurrence of PGIST in a patient diagnosed with recurrent MCSG on therapy. Surgeons might overlook the diagnosis of PGIST due to its rarity, especially when occurring synchronously with an also rare primary tumor such as MCSG. An asymptomatic, singular, and large mass that showed a well-circumscribed lesion with central necrosis and calcification in abdominal CT can be discovered either in pancreatic metastasis or PGIST. Upon finding such a pancreatic lesion in a patient with a history of cancer, one may consider pancreatic metastasis as the first diagnosis, followed by other etiologies such as pancreatic neuroendocrine tumor (PNET) or PGIST. Debating the properness of surgical role in secondary pancreatic cancer is not quite rhetoric. Curative resection can be performed in a patient with a single metastatic lesion and a good performance score. CD117 or KIT/receptor tyrosine kinase is a proto-oncogene expressed by the interstitial cell of Cajal (ICC), a progenitor cell of GIST which is a highly sensitive and specific marker for GIST. Although CD117 can be also expressed in the immunohistochemistry of MCSG, it cannot be considered a reliable marker for the diagnosis of a particular salivary gland tumor. Both parotid and pancreatic tissues showed positive stains for smooth-muscle actin (SMA) and CD34. But positive CD117 can only be found in pancreatic tissue confirming PGIST as the diagnosis of pancreatic mass instead of metastatic lesion.
Conclusions : This case showed that there is a possibility of double primary malignancies which involve both rare histopathology and organs. When there is a newly formed lesion in a distant organ, surgeons have to exclude the possibility of metastasis, not to avoid surgery but to decide the need for adjuvant therapy.
Methods : We report a case of double primary of synchronous malignancy of MCSG and PGIST with physical examination, radiological documentation, and specimen.
Results : This report describes the occurrence of PGIST in a patient diagnosed with recurrent MCSG on therapy. Surgeons might overlook the diagnosis of PGIST due to its rarity, especially when occurring synchronously with an also rare primary tumor such as MCSG. An asymptomatic, singular, and large mass that showed a well-circumscribed lesion with central necrosis and calcification in abdominal CT can be discovered either in pancreatic metastasis or PGIST. Upon finding such a pancreatic lesion in a patient with a history of cancer, one may consider pancreatic metastasis as the first diagnosis, followed by other etiologies such as pancreatic neuroendocrine tumor (PNET) or PGIST. Debating the properness of surgical role in secondary pancreatic cancer is not quite rhetoric. Curative resection can be performed in a patient with a single metastatic lesion and a good performance score. CD117 or KIT/receptor tyrosine kinase is a proto-oncogene expressed by the interstitial cell of Cajal (ICC), a progenitor cell of GIST which is a highly sensitive and specific marker for GIST. Although CD117 can be also expressed in the immunohistochemistry of MCSG, it cannot be considered a reliable marker for the diagnosis of a particular salivary gland tumor. Both parotid and pancreatic tissues showed positive stains for smooth-muscle actin (SMA) and CD34. But positive CD117 can only be found in pancreatic tissue confirming PGIST as the diagnosis of pancreatic mass instead of metastatic lesion.
Conclusions : This case showed that there is a possibility of double primary malignancies which involve both rare histopathology and organs. When there is a newly formed lesion in a distant organ, surgeons have to exclude the possibility of metastasis, not to avoid surgery but to decide the need for adjuvant therapy.
SESSION
E-poster
E-Session 03/23 ~ 03/25 ALL DAY