The prognosis of patients with PALN micrometastasis was extremely poor as well as HE-positive PALNs. However, postoperative adjuvant chemotherapy may contribute to improving the prognosis of PDAC patients with PALN metastasis.

HighlightsIntestinal obstructions caused by external compression from the appendix are rare.Low-grade appendiceal mucinous neoplasm (LAMN) with torsion is rarer still.LAMN have the potential to lead to pseudomyxoma peritonei.Surgical resection for LAMN is the standard treatment.The appropriate surgical procedure, however, remains controversial.

HighlightsFew cases of splenic hamartomas associated with thrombocytopenia have been reported.Imaging findings in splenic hamartomas are non-specific, variable, and making definitive preoperative diagnosis difficult.Surgery is necessary for diagnosis when malignancy cannot be ruled out.Surgery may also improve symptoms of hypersplenism, including thrombocytopenia.

HighlightsAppendiceal neurofibromas (AN) in Neurofibromatosis type (NF) 1 are rare.AN in NF1 with Low-grade appendiceal mucinous neoplasms (LAMNs) are extremely rare.AN and LAMNs have potential for malignant transformation.Surgical resection is the standard treatment for patients with AN and LAMNs.However, appropriate surgical procedure remains controversial.

HighlightsMixed adenoneuroendocrine carcinomas (MANECs) of the distal bile duct are extremely rare.The treatment of MANECs of the bile duct remains controversial and the prognosis is poor.Larger studies are required to establish standard treatment regimens of MANECs of the bile duct.