Surgical Oncology – Cancer
- Melanoma in-situ. 5mm resection margin is needed. (only 5 mm). In Situ = outer layer of the skin only (epidermis only)
- Currently Melanoma SLN positive mandates lymphadenectomy in melanoma.
- Patients with Familial Adenomatous Polyposis and Desmoids, ~10% of the tumors will have a very rapid and aggressive course. In FAP, there is a nearly 100 percent risk of colorectal cancer in the absence of treatment for polyposis.
- Uncontrolled local recurrence is the main cause of death with retroperitoneal sarcomas.
- Radiation therapy generally has not been shown to help low grade completely resected extremity sarcomas.
- Flat colorectal polyps: ~25% contain high grade dysplasia.
- SLN in colorectal cancer increases the accuracy of lymph node cancer status but often does not change the operation.
- Stage III colorectal cancer, all chemotherapy regimens seem to improve outcome. Another related topic: Stage 4 colon cancer.
- T2 colorectal lesions have a local recurrence rate of about 22%. With resection you induce a 20% local recurrence rate on a T2 cancer which had a 80% cure rate before resection. Salvage operations for local recurrence are associated with a 40-60% cure rate. Therefore, there is a 20% chance that a T2 patient survival will be reduced by doing a local resection (ie. transanal).
- Rectal cancers. Size of an adenocarcinoma after initial preoperative chemotherapy is more predictive than the initial size of the tumor.
- More advanced Gallbladder tumors, stage II, should be treated with a completion radical cholecystectomy – partial hepatectomies of the gallbladder bed with hepatoduodenal lymphadenectomy. Stage II: This means that cancer has grown through the muscle layer of the gallbladder wall and into the connective tissue underneath. It has not spread outside the gallbladder. Stage 2 in the TNM stages is the same as T2, N0, M0.
- Metastasis found in remote lymph nodes in gallbladder cancer portend a poor prognocis.
- PET scans doesn’t help distinguish acute or chronic cholecystitis vs. gallbladder cancer.
- Endoscopic ultrasound should be used often in evaluating patients with pancreatic cysts.
- If a pancreatic cyst wall has any nodularity then it may be malignant or on it’s way.
- Pancreatic cancer, the risk of malignancy is lower for side branch intraductal papillary mucinous neoplasm than for main duct IPMNS.
- Statistically, patients with pancreatic intraductal papillary mucinous neoplasms have an increased risk of colon and breast cancer.
- Jaundice is not an emergency. First understand the root cause before reflexively draining the bile duct.
- Parenchymal metastasis from a primary tumor such as lung metasis or liver metastasis, etc – those pts tend to do very poorly with peritoneal chemotherapy.
- GIST (Gastro Intestinal Stromal Tumors) – standard therapy is gleevec (IMATINIB). Metastatic disease may have resistance to the drug
- For patients with Colon cancer primary with metastasis to the liver with < or = 6 tumors in the liver where R0 resection (resection for cure) can be done, then these patients are reasonable candidates for resection surgery.
GIST – Gastrointestinal Stromal Tumor
- GISTs may be malignant or benign
- More common in the stomach and small intestine but can be found anywhere along the GI tract.
- Begins in cells called th interstitial cells of Cajal (ICC) – considered the pacemakers of the GI tract
- GIST may have a genetic component. Neurofibromatosis type 1 is linked to GIST.
- Partial resections are usually adequate with GIST treatment with negative margins. Formal gastrectomy is not usually necessary, nor is partial gastrectomy with nodal dissection. Organ sparing approaches are usually appropriate.