A Rare Case of Non-Umbilical Cutaneous Metastasis as a First Presentation of a Very Aggressive Pancreatic Cancer — A Case Report and Review of Literature

Abstract

Pancreatic cancers are highly aggressive cancers with metastasizing and invasive properties due to its oncogenic background. Treating metastatic disease has always remained a challenge where the mainstay of treatment remains palliative. They usually present at advanced stages due to non-specific early signs and symptoms. We present a case of a very aggressive pancreatic adenocarcinoma presenting initially as non-umbilical cutaneous metastasis which on subsequent workup revealed unusual genetic mutations and the involvement of multiple unusual sites of metastasis.1363_A.tif Figure 1: Skin lesion as initial presentation of metastatic pancreatic cancer.1363_B.tif Figure 2: Skull bone involvement of aggressive pancreatic tumor1363_C.tif Figure 3: PET-CT showing diffuse metastatic pancreatic disease involving bone, brain, lung, liver, spleen, subcutaneous tissue, muscle and GI tract.This is a case of a 76-year-old gentleman with past medical history of hypertension, alcohol abuse and ex-smoker who initially presented to dermatology clinic with a progressively enlarging lump over his frontal scalp. Skin biopsy revealed dermal involvement of metastatic adenocarcinoma favoring primary gastrointestinal origin. Further workup with esophagogastroduodenoscopy and colonoscopy did not reveal any mass lesions. Positron emission tomography (PET-CT) scan revealed a hypermetabolic pancreatic mass with multiple metastatic lesions involving the calvarium, scalp tissue, occipital lobe of the brain, subcutaneous tissue of the neck, lung, ribs, paraspinal muscles, liver, colon, spleen, psoas and gluteus maximus muscle. His CA 19-9 was >9000 U/mL, consistent with the extensive metastatic disease. Next-generation sequencing analysis revealed multiple poor prognostic and rare mutations. Even though he was asymptomatic at presentation, he very rapidly deteriorated within 6 weeks of presentation and died. Pancreatic cancers are very aggressive cancers which are a genetically evolving and heterogeneous. Metastatic pancreatic cancers presenting at unusual sites are very rare and constitute only <10 % of all cases. To the best of our knowledge, our case is the first one to be reported so far, of a metastatic pancreatic cancer with multiple involvement of unusual sites and with an initial presentation as a non-umbilical cutaneous lesion. The extremely aggressive nature, metastatic seeding at unusual sites and presence of unique genetic mutations reflect subgroups of this cancer with different molecular biology. Identifying these groups may have utility in determining prognosis and stratifying treatment for patients. This will hopefully translate into better diagnostic tests and therapies in near future