Casefiles 12: sarcomas Flashcards
most patients with STSs (soft tissue sarcomas) do not present with ?
but some do present with ?
NO regional LAD or systemic symptoms such as weight loss, night sweats, or cachexia
some produce local erythema, pain, and tenderness as the result of tumor necrosis
diagnosing sarcomas
core-needle (larger than 14-16 gauge needle)
If the core-needle biopsy is nondiagnostic, an open incisional biopsy should then be performed
NOT excisional biopsy
Excisional biopsies of suspected STSs are strongly discouraged because they frequently are associated with ?
positive resection margins, which necessitate additional surgeries for local disease control
Once STS is confirmed by biopsy, it is necessary to do what prior to tumor resection?
stage the patient’s disease locally and systemically
MRI, CT for local extent and of chest, abdomen, and pelvis for mets
STS treatment
Surgical resection with microscopically clear margins
radiation therapy if stage II or III
some evidence to suggest that patients with high-risk (stage IIB+) STSs may derive some benefits with adjuvant systemic chemo
STS staging is based on what?
tumor size (less than/= 5 cm or greater than 5 cm)
depth (superficial or deep to fascia)
nodal involvement (+) or (–)
metastasis (+) or (–)
histologic grade (well-, moderate-, or poorly-differentiated)
resection criteria
R2: Surgical resection with gross (+) margin involvement (rarely done, little benefit)
R1: Surgical resection with gross (–) margin but microscopically (+) margin
R0: Surgical resection with microscopically (–) margin (primary goal of surgery)
What mutation has been identified in 80% to 85% of GISTs (GI stromal tumors)
5% to 7% of GISTs occur as the result of ?
A gain-of-function mutation in the tyrosine kinase receptor (KIT)
primary platelet-derived growth factor receptor alpha (PDGFRA)
Carney’s triad
original: GIST, paraganglioma, and pulmonary chondroma
recent addition of esophageal leiomyoma and adrenal adenoma
Tyrosine kinase inhibitors (TKIs)
postoperative adjuvant therapy for high-risk and/or metastatic GISTs (improve resectability)
first-line-imatinib, second-line-sunitinib, and third-line-regorafenib
Soft tissue sarcomas (STSs) are a heterogeneous group of solid, mesenchymal cell tumors originating from ?
muscle, fat, vascular tissue, fibrous connective tissue, peripheral neural tissue, and visceral tissue
breakdown of STS location
60%: extremities, 20%: truncal region, 15%: intra-abdominal or retroperitoneal, 5%: head and neck region
?% of patients with STSs have distant metastases at presentation, with ? being the most common site.
10%
the lungs
Currently, the guiding principle in STS surgery is to achieve ? of uninvolved tissue margins or an intact fascia in the resected specimen
greater/= 2.0 cm
Known physical factors for sarcoma development include ?
history of radiation, lymphedema, and chemical exposures (including prior chemotherapy)
genetic conditions associated with sarcomas
Neurofibromatosis Li–Fraumeni syndrome Retinoblastoma Familial polyposis coli (Gardner syndrome) p53 and Rb-1 mutations
presentation of retroperitoneal sarcomas
diagnose with ?
early satiety and lower extremity venous congestion (compressive, as median size at dx is 15-20cm)
CT/MRI, usually don’t need biopsy, but if uncertainty can use image-guided core needle
most retroperitoneal sarcomas are ?
do the metastasize?
liposarcomas
rarely metastasize to distant sites
GIST specifically refers to a tumor arising from the GI tract with a ? mutation
KIT or PDGFRA-activating mutation
sites of GIST
stomach (50%-70%), small bowel (25%-15%), colon and rectum (5%-10%), omentum (7%), and esophagus (less than 5%)
What is the most common symptom related to GISTs, mostly as the result of ?
the most common sites of metastasis are ?
Bleeding due to tumor necrosis
the peritoneum, omentum, and liver
imaging modality most commonly used for diagnosis of GIST prior to surgery
CT + contrast, MRI if in rectum/pelvis
Most gastric GISTs can be resected by either a ? or ? Small bowel and colorectal GISTs are treated by ?
wedge resection or partial gastrectomy
segmental resections
Extremity STSs do not have pathognomonic characteristics based on imaging that can establish diagnosis therefore ? is the only way to determine the diagnosis
Tissue sampling
One-year of ? has been found to reduce recurrence following the resection of high-risk GISTs (tumor greater than 3 cm, nongastric origin, and greater than 5-10 mitotic figures/50 HPF)
imatinib adjuvant therapy
*effective only for patients with GISTs with c-kit mutations
