High Yields 2018 Qs Flashcards
How does the PD-1/PD-L1 interaction relate to tumor growth?
TEST QUESTION
Programmed cell death protein 1 (PD-1) is a transmembrane protein expressed on T cells, B cells, and natural killer (NK) cells. It has an inhibitory effect and binds to the programmed cell death ligand 1 and 2.
PDL-1 is expressed on the surface of multiple tissue types, including many tumor cells, as well as hematopoietic cells.
PD-1 is the negative regulator of cell activation.
The tumor microenvironment up-regulates PD-1 on tumor reactive T cells, and contributes to impaired antitumor immune responses (the PD-1/PDL-1 intercation inhibits apoptosis of the tumor cell)
- PD-1 inhibitors:
Nivolumab
Pembrolizumab
Cemiplimab
Dostarlimab
Retifanlimab
Toripalimab
Tislelizumab
PDL-1 inhibitors:
Atezolizumab
Avelumab
Durvalumab
CTLA-4 inhibitors:
Ipilimumab
Tremelimumab
what are Interferons?
non specific immune modulators named for interfering with viral machinery
*INF Gamma upregulates PD-1 and PDL-1. It is also an important activator of macrophages and inducer of major histocompatibility complex class II molecule expression.
what part of the Her2 receptor is the target of intervention? (ie: Intracellular, tyrosine kinase, extracellular, transmembrane)
extracellular portion
What is the other name for protein Ca125?
The gene for CA 125 is called MUC16 or mucin16
What distinguishes PSTT from choriocarcinoma?
1.INTERMEDIATE trophoblasts
2.Human Placenta Lactogen
3. Lower betaHCG
*all of these
What distinguishes endometrial stromal nodule (ESN) from low grade endometrial stromal sarcoma (LG-ESS)?
A ESS has more mitoses
B ESS has more atypia
C presence of spiral arterioles
D absence of LVSI in ESN
Absence of LVSI is the correct answer choice
The histologic features of ESN are identical to LG-ESS but ESN has a circumscribed, noninfiltrating border without evidence of myometrial or vascular invasion. ESN is a benign neoplasm that is cured with simple hysterectomy.
B&H: Because diagnosis is based on complete circumscription and absence of lymphovascular invasion, the distinction between stromal nodule and stromal sarcoma can usually be made only at the time of hysterectomy.
Ratio of tumor markers for ovca and colon cancer?
CA125/CEA (this one, 25:1), HE4/CEA
Picture of pap serous uterine cancer histology
pap serous
other test options that are wrong: LMS, endometrioid
Architecture:
Papillary with or without appreciable fibrovascular cores; micropapillary pattern can be seen
Slit-like spaces
Gland-like spaces may be observed
Psammoma bodies may be present in up to 33% of cases
Cytoplasm usually scant but can be abundant with eosinophilia or clearing
Tumor cells can colonize existing endometrial glands
Tumor cells can appear discohesive
Nuclei are typically high grade with pleomorphism, hyperchromasia, prominent nucleoli and frequent mitotic figures (including atypical mitotic figures)
Napsin A (IHC stain)
clear cell carcinoma
- Immunophenotype: most often lacks estrogen receptors and WT-1. Do have: p53 expression, napsin-A, hypoxia-inducible factor 1 alpha (HIF-1 alpha), glypican-3, and hepatocyte nuclear factor 1-beta (HNF-1 beta).
POLE mutated (group 1)
excellent prognosis regardless of grade POLE (why? high tumor mutation burden, tumor neoantigen production, and tumor infiltrating T cells)
MSI hypermutated (group 2)
Most common methylation of MLH1; also can have mutated MLH1, MSH2, MSH6, PMS2; MLH1 + PMS2, MSH2 + MSH6 form dimers so if one degraded the other is; immunotherapy candidates if recurrent; radiation beneficial
High TMB ≥10 mutations/megabase > pembrolizumab.
dMMR/MSI-H: pembrolizumab or dorstalimab.
Tumors without dMMR or high TMB: Pembrolizumab plus lenvatinib
MSS/copy number low (group 3 - PTEN, ARID1A, PIK3CA mut, ER/PR pos)
Good prognosis; respond to hormonal therapy; PI3K/mTOR inhibitors for metastatic disease
Copy number high (group 4) of endometrial cancer molecular subgroup is most likely what histology?
serous; p53 mutated; poor prognosis; trastuz if HER2 +/ERBB2 amp
what are the most common MMR defects in Hnpcc?
MLH1/MSH2 (this one); PMS2, MSH6
MLH1 and MSH2 genes are by far the most commonly mutated in Lynch syndrome patients accounting for ~70% of the mutations identified (32% in MLH1 and 38% in MSH2)
KRAS associations?
Type 1 ovary tumors, mucinous histology ; also recurrent low grade serous carcinoma (unlike BRAF)
Integrin role in cancer?
metastases role (cell invasion and migration)
adhesion of leukocytes to endothelial cells
Mechanism of ERBB2 oncogenicity?
AMPLIFICATION of oncogene producing HER2 protein
How do kinases work?
Phosphorylation
*Tyrosine kinases are enzymes that selectively phosphorylates tyrosine residue in different substrates. Receptor tyrosine kinases are activated by ligand binding to their extracellular domain. Ligands are extracellular signal molecules (e.g. EGF, PDGF etc) that induce receptor dimerization (except Insulin receptor) and a cascade of events.
Which of the following is a tumor site not included in risk for HNPCC ?
A breast
B gastric
C pancreatic
D urethral
E brain
“breast // does include endometrial, colon, gastric, ovarian, pancreatic, urethral, brain (glioblastoma), small intestinal,
sebaceous gland adenomatous polyps, keratoacanthomas
Histopath of leiomyosarcoma?
List 3
-prominent cellular atypia
-abundant mitoses (≥10 per 10 high power fields)
-areas of coagulative necrosis
*Two of these are necessary for a diagnosis
Grade 1 endometrioid, young, normal weight - tumor most likely to express:
A MSH2
B CK7
C ER
D PR
MSH2
Germ cell tumor least likely to have elevated AFP
Dysgerminoma and choriocarcinoma both not elevated
Genetic mut associated with type I endometrial cancer
PTEN (PTEN tumor suppressor is the most important negative regulator of PI3K signaling)
How does Loss of heterozygosity occur (two mechanisms)
Deletion (most common) or methylation
*Loss of heterozygosity: refers to a type of mutation that results in the loss of one copy of a segment of DNA
*LOH occurs when a cancer cell that is originally heterozygous at a locus loses one of its two alleles at that locus, either by simple deletion of one allele (copy-loss LOH), or by deletion of one allele accompanied by duplication of the remaining allele (copy-neutral LOH). When a cancer cell undergoes LOH of an essential gene, further loss or inhibition specifically of the allele retained in the tumor should not be tolerated, whereas normal cells will be able to survive relying solely on the remaining allele
High LET has what effect on cancer cells?
Tumor necrosis, higher LET is more direct damage
*Linear energy transfer (LET) average amount of energy lost per unit track length in tissue by a type of radiation
*High LET radiation: particles with substantial mass and charge such as alpha particles or neutrons
*Low LET radiation: X-rays, gamma rays
Elevated CA19-9 and CEA
mucinous tumor
Downstream effect of VEGF receptor binding
Capillary permeability (THIS ONE), increased intratumor pressure, other options
Cowden
What is the germline mutation?
Clinical picture (non-cancer)?
Screening?
PTEN
Clinical picture: GI polyps, thyroid disease, benign breast disease, mucocutaneous lesions
Cancer risk: breast, thyroid, endometrial
Screening for breast cancer: breast self awareness from 18yo, clinical breast exam q6-12mo from age 25 (or 5-10 years before earliest family dx), annual MMG+MRI from 35yo (or 10 years before earliest family dx) per NCCN 6/2023
Screening for colon: start c/scope age 35-40 or 5-10yr before earliest family dx)
Screening for endometrial cancer: start 35yo. prompt eval of AUB. consider q1-2yr EMB per NCCN 6/2023
invasive/image screenings all start at 35
Cowden most common GYN cancer
Endometrial cancer (lifetime risk 19-28%)
Cowden most common cancer
Breast
- The lifetime risk of breast cancer for affected female patients is frequently reported at between 25 and 50 percent, although more recent reports project a cumulative risk as high as 81 to 91 percen
What causes invasion through the basement membrane?
MMP
Matrix metalloproteinases
Function of integrins?
migration and invasion
What tumor is associated with FOXL2 mutation?
Granulosa cell tumor
*FOXL2 encodes a transcription factor that is expressed as a nuclear protein and is critically important in the development of granulosa cells. Somatic mutations in FOXL2 have been identified in 97 percent of adult subtype granulosa cell tumors and only 1 of 10 juvenile subtype granulosa cell tumors
Which common medication inhibits the mTOR pathway?
Metformin
Which of the following is an oncogene: listed choices were PTEN, P53, BRCA and c-myc?
c-myc
CA 125 is also known as?
MUC 16
*Direct questions
BRAF mutation in which ovarian tumor?
low grade serous
What type of endometrial cancer is associated with p53 and her2neu?
Type II endometrial cancer
Copy number High
Kras mutation in which ovarian histology- mucinous, serous, clear cell, endometrioid?
MUCINOUS
*Direct question: also low grade serous, this was 2 different questions on the exam
First step in carcinogenesis of ovarian cancer: p53 mutation, fallopian tube stic, a few other options - which one?
p53 mutation
MC germline mutation in ovarian cancer?
BRCA 1
Mutation most common in p53?
Missense mutation
Exons 5-8
How do you protect vulva skin during radiation?
anti fungal
estrogen cream
positioning (frogleg)
cold packs
Using a diluted water/H2O2 rinse
positioning (frogleg)
Based on MCG RadOnc text consult
Diluted hydrogen peroxide water on the vulvar during EBRT to decrease - Wake RadOnc Lecture
How does HDR differ from LDR?
decreased treatment time
How does cisplatin augment radiation?
inability to repair DNA
What radiation source the longest half-life?
Radium
-cesium 137 - 30 years
-irdium 192 - 74 days (SHORTEST)
-radium 226: very long like 1600 years
-colbalt 60 - 5 years
What is the half life of cesium?
30 years
What type of radiation is produced by cobalt ?
Gamma
Cobalt (Gamma ray, from nucleus, avg Cobalt energy is ~1.25MeV)
What is most sensitive to side effects from pelvic radiation?
ileum
*2 questions on this topic
What do you call the area around the gross tumor volume that might have microscopic tumor?
clinical target volume
Inverse square law, if you go from 2 cm to 1 cm how much does dose increase?
400%
*this is on every year
The radiation inverse square law specifies that: the intensity of the radiation goes down by the square of the distance from the source. For instance if you move twice as far from the source the intensity of the radiation will decrease by a factor of 4.
Intensity = 1 / (distance ^2)
Adjuvant treatment for positive right inguinal lymph node?
bilateral radiation to nodes and pelvic field
XRT vs brachy - which symptom is shared?
FATIGUE (answer)
-wrong answers: vaginal stenosis, 2 other
Which chemo causes delayed bone marrow suppression?
TEST QUESTION
mitomycin C
Marrow suppression at 28 to 42 days with recovery 40 to 60 days after treatment
And Melphalan and chlorambucil
Which drug do you need to dose reduce for renal insufficiency?
A bev
B vinca
C taxol
D etoposide
**TEST QUESTION **
Etoposide
A BICC THE MMP require renal dosing modifications
ActD,
Bleo, ifos, cytoxan, capecitabine,
Topo, hydroxyurea, etopo,
mtx/pemetrexed, melphalan, platinum (carbo/cis, oxali)