<p>Skin Metastasis of Gastrointestinal Stromal Tumors: A Case Series and Literature Review</p>

Abstract

Background: Gastrointestinal stromal tumors (GISTs) extremely and rarely metastasize to the skin, and such metastases have not been well characterized. Methods: Retrospective analysis of clinicopathological data of patients with skin metastasis of a GIST (SM-GIST) admitted to Xiangya Hospital (Changsha, Hunan, China) and literature review were conducted. Results: Including our 4 cases, a total of 17 cases have been reported to date. The mean age of the patients was 55.4 years (29~70 years) and there was not sex predominance (male 10 and female 7). Primary tumors were often located in the stomach (n=9), duodenum (n=2) and small bowel (n=2). Meanwhile, SM-GIST mainly occurred in head and face (n=6), extremities (n=6), followed by abdomen wall (n=5), back (n=3) and chest (n=2). Mutation analysis revealed that the frequency of wild-type GIST (WT-GIST), exon 9, 11 and 13 mutations was 6, 1, 4 and 1, respectively. The average time to SM-GIST was 4.22 years, specifically 4.59 years in gastric and 3.8 years in non-gastric. Moreover, for the resection only group (including chemotherapy), such average time was 3.63 years, while for the combined group (resection and tyrosine kinase inhibitors (TKIs)), it was about 4.74 years. The mean survival was approximately 6.2 years. However, after the diagnosis of SM-GIST, survival was only about 1.69 years. Conclusion: SM-GIST is a rare malignant condition. Non-gastric GIST, surgery without TKIs, high invasiveness and tumor burden, and molecular subtype (mutation in exon 9, 11 and wild-type) may be conducive to the development of SM-GIST. Additionally, it is also a sign of poor prognosis.

Primary vulvar extragastrointestinal stromal tumor in a 77‐year‐old woman

“…Although the diagnosis of GIST or EGIST can be made based on histopathology and immunohistochemistry, molecular testing for mutations can be useful and also has treatment implications. The use of tyrosine kinase inhibitors (including imatinib, sunitinib, and regorafenib) has led to improvements in survival for patients with localized or advanced KIT ‐mutant GISTs 46,47 . Mutational analysis of the current case showed KIT exon 11 and SF3B1 mutations.…”

Primitive Cutaneous (P)erivascular (E)pithelioid (C)ell Tumour (PEComa): A New Case Report of a Rare Cutaneous Tumor

“…cPEComa must be differentiated from skin metastasis by gastrointestinal stromal tumours (GISTs): about 10% of GISTs can metastasise to the skin [ 30 , 31 ]. In the metastatic setting, however, GISTs retain their characteristic immunophenotypic spectrum (positive for DOG-1 and CD117) and also other possible markers, including CD34 (70%), SMA (30-40%), S-100 protein (5%) and desmin (1–2%) [ 31 ].…”

Clinical characteristics and prognosis of gastrointestinal stromal tumors with rare site metastasis (Review)

“…Furthermore, when GIST metastasizes to the lungs, signs and symptoms that may be observed include dyspnea, blood in the sputum, coughing and shortness of breath (18,85,88,97). When metastasis to superficial lymph nodes, skin or subcutaneous tissue occurs, a mass may be superficially palpable (28,42,45,55,68,68,73,98). However, when GIST metastasizes to the heart, although no clinical signs are evident in the early stages (24,82,83,99,100), the late stages may manifest as cardiogenic shock (43).…”