Chapter 16 Flashcards
What is the 5th most common cancer type?
Melanoma
What is the most common cause of melanoma?
BRAF mutation (60% of melanomas)
Age of melanoma
Wide range, often in women 20-30 yrs
Race predilection of melanoma
White 30x more likely
Hx of melanoma lesion
Recently developed or changing OR
FHx of CDKN2A or CDK4
Environmental factors of melanoma
UV radiation
Presentation of melanoma
Asymmetry Irregular borders Color Diameter >6 mm Elevated surface
What is the most suspicious melanoma?
Superficial spreading > nodular melanoma > lentigo maligna > acral lentiginous
What is the MC noncutaneous melanoma?
Ocular melanoma
What is associated with a worse prognosis in pts with disseminated melanoma?
Elevated LDH
What type of margins should be achieved with less than or equal to 1 mm thickness melanoma?
1 cm margin
What type of margins should be achieved with 1-2 mm thickness melanoma?
1-2 cm
What type of margins should be achieved with >2 cm thickness melanoma?
2 cm
What is the MC site for the first metastasis of melanoma?
Regional LNs
What is now the standard procedure for detecting subclinical metastatic to the regional nodes?
Sentinel LN bx
When is surgical resection recommended for melanoma?
Pts with primary tumors >1 mm, with tumor thickness of 0.76 to 1 mm who have T1b lesions, and tumor thickness of 0.76 to 1 mm who have T1a lesions
When is resection not recommended in melanoma?
Pt with tumor thickness <0.76 mm
What high-risk features are rare in thin lesions but when present may warrant sentinel LN bx in selected individuals in whom it is not otherwise recommended? (melanoma)
High mitotic rate Lymphovascular invasion Microsatellites Clark level IV Ulceration
What is the single strongest prognostic factor for pts with clinically localized melanoma?
The status of the sentinel node
How is a melanoma lesion identified?
Tech-99m labeled sulfur colloid
-Accuracy of the procedure is maximized by the additional intraoperative injection of isosulfan blue dye into the tumor site, which allows both visualization of the blue sentinel node and detection with a handheld gamma probe
What is recommended in stage II melanoma, in the absence of distant metastases
Therapeutic lymph node dissection
What is located in the inguinal region?
The superficial femoral nodes, which reside in the triangle between the sartorius muscle laterally; the adductor muscles medially; and the inguinal ligament superiorly
Where do the parotid, submandibular, submental, jugular, and posterior triangle lymph nodes drain?
Anterior to the ear and superior to the mouth
Where do anterior lesions inferior to the mouth drain?
To cervical nodes
Where do posterior lesions drain?
To occipital, postauricular, posterior triangle, and jugular nodes
What are complications of lymph node dissection?
Infection
Wound dehiscence
Seroma
Lymphedema
Who is at a high risk for local recurrence despite therapeutic lymph node dissection?
Pts with lymph node metastases that grow through the capsule of the lymph node (extracapsular extension) and those with extensive tumor burden in multiple nodes
-Consider adjuvant radiation therapy
In-transit metastases- lymphatic
Tumor deposits along the path of lymphatic drainage from the primary tumor to the regional lymph node basin
Prognosis of in-transit metastases- lymphatic
Worsens with increasing number
Tx of in-transit metastases- lymphatic
Excision and sentinel lymph node bx or dissection
Additionally, isolate limb perfusion (ILP) and isolated limb infusion (ILI) have also been used
Local recurrence of advanced lymphatic metastases
Regrowth of tumor within 5 cm of the primary resection site
4% rate of recurrence
Occurs more frequently in pts with thick (>4 mm) primary lesions and ulcerated tumors and in lesions of the foot, hand, scalp, and face
Distant metastases lymphatic
To the lung, liver, brain, and bone are most common
Tx options for distant lymphatic metastases
Observation- often warranted for asymptomatic pts in poor medical condition
Surgical resection of metastases- resection can provide effective palliation and a 5-yr survival of up to 29%
Radiation therapy- Palliative tx for symptomatic lesions and brain metastases
Chemo- combo regimens include dacarbazine are used predominantly but are now reserved for pts failing other options
Target therapy for distant metastases- lymphatic
BRAF inhibitors (vemurafenib, dafrafenib) target the activating mutation in BRAF (present in 60% of melanomas). Response rates of 50% but resistance develops after a median of 9 mos MEK inhibitor (trametinib) often in combo with BRAF inhibition
Biologic therapy for distant metastases- lymphatic
IL-2 results in 10-20% response rate (some responses are dramatic) but largely supplanted by ipilimumab
Anti-CTLA-4 antibody (ipilimumab) is associated with modest response rates but substantially improves overall survival
Anti-PD-1 antibody (pembrolizumab) recently demonstrated improved response rates and overall survival compared to ipilimunab in a phase II trial
Soft tissue sarcoma
Malignant tumors of the mesenchymal origin (fat, muscle, connective tissue)
Most occur on the LEs and retroperitoneum is 2nd MC
Genetic syndromes associated with soft tissue sarcoma
Gardner syndrome
Retinoblastoma
Neurofibromatosis I
Types of soft tissue sarcoma
Leiomyosarcoma MC
Rhabdomyosarcoma (MC childhood sarcoma)
What is the mainstay of therapy for soft tissue sarcoma?
Surgical resection
What is the prognosis of retroperitoneal sarcoma?
15%, poor prognosis
GIST
GI stromal tumor, rare, from interstitial cells of Cajal, receptor KIT (CD117), surgical resection is the mainstay of therapy if localized
What percentage of lymphomas does Hodgkin lymphoma constitute?
10%
Characteristics of Hodgkin lymphoma
A malignancy of B cells and can be characterized pathologically by the presence of Reed-Sternberg cells
Bimodal age distribution with first peak at ~20 yoa and a second peak at age 65
What is the most common presentation of Hodgkin lymphoma?
Painless LAD
What are the most commonly involved sites in Hodgkin lymphoma?
Cervical/supraclavicular lymph node basins followed by the axillary and inguinal node basins
Alternate presentation of Hodgkin lymphoma
Incidentally discovered mass on imaging- most commonly a mediastinal mass with retroperitoneal adenopathy seen less frequently
Other sx in Hodgkin lymphoma
Fever >38 degrees Celsius
Night sweats
Wt loss of more than 10% body weight over a 6-mo period
AKA B sx
What does an eval of pts referred for lymph node bx for Hodgkin lymphoma include?
PE with detailed evaluation of all accessible lymphatic tissue
-Palpation of all superficial lymph node basins and abdominal palpation for hepatic or splenic enlargement
Diagnostic laboratory studies for Hodgkin lymphoma
CBC with diff
Peripheral blood smear
What is staging in Hodgkin lymphoma based on?
The extent of disease and the present or absence of B sx
Staging workup for Hodgkin lymphoma
Liver function
LDH
ESR
CXR
CT scan (typically neck, chest, abdomen, and pelvis)
PET scan
Bone marrow bx recommended for stage IB, IIB and III-IV
What is the tx modality of choice Hodgkin lymphoma?
Chemoradiation for all pts with stage I-II
Chemo , with or without radiation for more advanced stages
Presentation of NHL
Can vary widely from an indolent course over yrs to an acute presentation that can be fatal within wks
How are NHL tumors classified?
By their cell of origin (B cell, T cell, or rarely NK cells) with most cases of B-cell descent (80%)
Presentation of NHL
More than 2/3 of pts with NHL present with LAD
What is the surgeon’s role in NHL?
Obtain tissue for dx
Treat extranodal lymphomas in the GI tract
What is one of the few indications for urgent performance of a LN bx in NHL?
Suspicion of an aggressive NHL lymphoma
Gastric MALT
A clonal B-cell neoplasm typically associated with an indolent course but prone to local recurrence and occasionally capable of distant metastatic spread or degeneration into a high-grade B-cell lymphoma
What is MALT lymphoma classically associated with?
H. pylori present in >90% of cases
Tx of MALT lymphoma
For early dz, tx of H. pylori alone serves as a highly effective tx
For those with advanced dz or in whom H. pylori therapy fails, radiation therapy is typically highly effective with surgical resection reserved for cases in which radiation is contraindicated
What is the MC site of involvement for extranodal NHL?
GI tract
From where do the majority of GI lymphomas arise?
In the stomach (75%)
Presentation of gastric lymphomas
Abd pain Wt loss N/V Bleeding Rarely, perforation
Tx for gastric lymphoma
Surgical resection is rarely employed
Chemo is the therapy of choice
Surgery is now reserved for those rare pts who develop complications from the dz or during therapy
What are uncommon in the US but are the most common extranodal lymphoma in the Middle East?
Lymphomas of the small bowel
When are there higher incidences of small bowel lymphomas?
In pts with celiac dz
Where are lymphomas of the small bowel most often found?
Proximal jejunum
Presentation of small bowel lymphomas
Obstruction
Intussusception
Bleeding
Tx of small bowel lymphomas
Chemo is the mainstay
However, resection needs to be done to obtain a dx
Then, adjuvant chemo
What are the MC noncarcinomatous tumors of the large bowel?
Colonic lymphomas
