GI – Gastric Cancer – Rad Onc Clinical Review – Flashcards

Unlock all answers in this set

Unlock answers
question
What is the incidence of gastric cancer in the U.S. and worldwide?
answer
U.S: 21,130 cases/yr (in 2009), with 10,620 deaths (7th leading) ;;;;; Worldwide: ~875,000 new cases/yr; 2nd-leading cause of death (behind lung cancer)
question
Where are the high-incidence areas in the world?
answer
The highest incidences are found in East Asia (Japan and China) > South America > Eastern Europe.
question
What are some acquired risk factors for developing gastric cancer?
answer
Acquired factors: Helicobacter pylori infection, high intake of smoked and salted foods, nitrates, diet low in fruits/vegetables, smoking, RT exposure, obesity, Barrett esophagus/GERD, prior subtotal gastrectomy
question
What are some genetic risk factors for developing gastric cancer?
answer
Genetic factors: E-cadherin (CDH-1 gene) mutation, type A blood group, pernicious anemia, HNPCC (Lynch Syndrome), Li-Fraumeni syndrome
question
How does tumor location relate to the underlying etiology of gastric adenocarcinoma?
answer
Body and antral lesions are associated with H. pylori infection and chronic atrophic gastritis, whereas proximal gastric lesions (gastroesophageal [GE] junction, gastric cardia) are associated with obesity, GERD, and smoking.
question
Which has poorer prognosis: proximal or distal gastric cancer?
answer
Stage for stage, proximal gastric cancer has a poorer prognosis.
question
What are the 2 histologic types of gastric adenocarcinoma? How do these 2 types differ in terms of etiology of the gastric cancer?
answer
Intestinal and diffuse are the 2 histologic types of adenocarcinomas. Intestinal type are differentiated cancers with a tendency to form glands, occur in the distal stomach, and arise from precursor lesions seen mostly in endemic areas and in older people, more commonly men, suggesting an environmental etiology. Diffuse type are less differentiated (signet ring cells, mucin producing), have extensive submucosal/distant spread, and tend to be proximal. They do not arise from precancerous lesions, are more common in low-incidence areas, and are more common in women and younger people, suggesting a genetic etiology.
question
What is the the Borrmann classification of gastric cancer?
answer
The Borrmann classification is based on the gross morphologic appearance. It is divided into 5 types: Type I: polypoid/fungating ;;;;; Type II: ulcerating ;;;;; Type III: ulcerating/infiltrative ;;;;; Type IV: diffusely infiltrating (linitis plastica) ;;;;; Type V: cannot be classified (most aggressive)
question
What are the lymphatic drainages of the stomach as per Japanese Research Society (JRS)?
answer
1st echelon: N1—perigastric nodes (lesser and greater curvature) and periesophageal nodes (proximal gastric) ;;;;; 2nd echelon: N2—celiac axis, common hepatic, splenic ;;;;; More distant: N3—hepatoduodenal, peripancreatic, mesenteric root; N4—portocaval, PA nodes, middle colic ;;;;; Note: Japanese Research Society (JRS) N1-N4 are not the same as AJCC staging.
question
What are the patterns of spread for gastric cancer?
answer
Local extension to adjacent organs, lymphatic mets, peritoneal spread, or hematogenous (liver, lung, bone). Liver/lung mets are generally for proximal/GE junction tumors.
question
What is the superior anatomic boundary and organs for the stomach?
answer
Superior: diaphragm, left hepatic lobe
question
What is the inferior anatomic boundary and organs for the stomach?
answer
Inferior: transverse colon, mesocolon, greater omentum
question
What is the anterior anatomic boundary for the stomach?
answer
Anterior: abdominal wall
question
What is the posterior anatomic boundary and organs for the stomach?
answer
Posterior and lateral: spleen, pancreas, left adrenal, left kidney, splenic flexure of colon
question
What is the most important prognostic factor for gastric cancer?
answer
TNM stage is the most important factor, with the histologic grade and Borrmann types not being independently prognostic apart from tumor stage. However, in general, Borrmann type I and II are more favorable compared to type IV.
question
Is all nodal involvement equally prognostic for gastric cancer?
answer
No. The # and location of nodes are important. Min LN involvement adjacent to the primary lesion is more favorable.
question
How do pts with gastric cancer generally present?
answer
Anorexia, abdominal discomfort, weight loss, fatigue, n/v, melena, and weakness from anemia
question
What aspects of the physical exam are relevant for evaluating a pt for a possible gastric malignancy?
answer
General physical with focus on abdominal mass (local extension), liver mets, ovarian mets (Krukenberg tumor), distant LN mets (Virchow: left SCV; Irish: left axillary; Sister Mary Joseph: umbilical), ascites, Blumer shelf (rectal peritoneal involvement)
question
What studies should be performed in the workup for gastric cancer?
answer
Gastric cancer workup: H&P (onset, duration, Hx of risk factors), CBC, CMP, esophagogastroduodenoscopy (EGD) + Bx, EUS +/- FNA of regional LN mets, CT C/A/P, and diagnostic laparoscopy to r/o peritoneal seeding
question
How many layers are seen on EUS when imaging the GI tract? Name these layers.
answer
5 layers are seen on EUS: layers 1, 3, and 5 are hyperechoic (bright), and layers 2 and 4 are hypoechoic (dark). Layer 1 is superficial mucosa, layer 2 is deep mucosa, layer 3 is submucosa, layer 4 is muscularis propria, and layer 5 is subserosa fat and serosa.
question
What is the rate of upstaging to stage IV using diagnostic laparoscopy?
answer
35%-40% of pts are found to have mets using diagnostic laparoscopy.
question
Why is PET imaging not routinely used in staging gastric cancer?
answer
In 1 study, only approximately two thirds of primary tumors are FDG avid (Shah et al., Proc ASCO 2007), with GLUT-1 transporter rarely present on the common subtypes of gastric cancer (signet ring and mucinous). Therefore, there are too many false negatives.
question
Describe Tis in the AJCC 7th edition (2009) T-staging classification for gastric cancer?
answer
Tis: confined to mucosa without invasion to lamina propria
question
Describe T1a in the AJCC 7th edition (2009) T-staging classification for gastric cancer?
answer
T1a: invades lamina propria, muscularis mucosae, or submucosa
question
Describe T1b in the AJCC 7th edition (2009) T-staging classification for gastric cancer?
answer
T1b: invades submucosa
question
Describe T2 in the AJCC 7th edition (2009) T-staging classification for gastric cancer?
answer
T2: invades muscularis propria
question
Describe T3 in the AJCC 7th edition (2009) T-staging classification for gastric cancer?
answer
T3*: penetrates subserosa without invasion of visceral peritoneum (serosa). Note: *Tumor is classified as T3 if it penetrates through the muscularis propria with extension into the gastrocolic or gastrohepatic ligaments, or into the greater or lesser omentum without perforation of the visceral peritoneum covering these structures.
question
Describe T4a in the AJCC 7th edition (2009) T-staging classification for gastric cancer?
answer
T4a*: invades serosa. Note: *Tumor is classified as T4 if it penetrates the visceral peritoneum covering the gastric ligaments or the omentum.
question
Describe T4b in the AJCC 7th edition (2009) T-staging classification for gastric cancer?
answer
T4b: invades adjacent structures
question
Describe N1 in the AJCC 7th edition (2009) N-staging classification for gastric cancer?
answer
N1: 1-2 LNs
question
Describe N2 in the AJCC 7th edition (2009) N-staging classification for gastric cancer?
answer
N2: 3-6 LNs
question
Describe N3 in the AJCC 7th edition (2009) N-staging classification for gastric cancer?
answer
N3: >=7 LNs
question
Describe N3a in the AJCC 7th edition (2009) N-staging classification for gastric cancer?
answer
N3a: 7-15 LNs
question
Describe N3b in the AJCC 7th edition (2009) N-staging classification for gastric cancer?
answer
N3b: >15 LNs
question
Describe Stage IA in the AJCC 7th edition (2009) stage groupings for gastric cancer?
answer
Stage IA: T1N0 (adds to 1)
question
Describe Stage IB in the AJCC 7th edition (2009) stage groupings for gastric cancer?
answer
Stage IB: T1N1, T2a-bN0 (adds to 2)
question
Describe Stage IIA in the AJCC 7th edition (2009) stage groupings for gastric cancer?
answer
Stage IIA: T1N2, T2N1, or T3N0 (adds to 3)
question
Describe Stage IIB in the AJCC 7th edition (2009) stage groupings for gastric cancer?
answer
Stage IIB: T2N2, T3N1, T4aN0 (adds to 4)
question
Describe Stage IIIA in the AJCC 7th edition (2009) stage groupings for gastric cancer?
answer
Stage IIIA: T4aN1, T3N2, T2N3 (adds to 5)
question
Describe Stage IIIB in the AJCC 7th edition (2009) stage groupings for gastric cancer?
answer
Stage IIIB: T4bN0, T4bN1, T4aN2, T3N3 (adds to 6 mostly)
question
Describe Stage IIIC in the AJCC 7th edition (2009) stage groupings for gastric cancer?
answer
Stage IIIC: T4bN2, T4aN3, T4bN3 (adds to 7 mostly)
question
Describe Stage IV in the AJCC 7th edition (2009) stage groupings for gastric cancer?
answer
Stage IV: TXNXM1
question
What is the 5-yr OS for the various stages of gastric cancer?
answer
T1N0, 90%; T2N0, 52%; T3N0, 47%; T4N0, 15%; TXN1, 10%; TXN2, 10%; TXN3, 10%; TXN4, 3% (Japanese data: modified from Noguichi Y et al., Cancer 1989). These results may not reflect outcomes in the U.S. There is a chance that the biology of gastric cancer is different in Japanese cohorts and that gastric cancer screening is used in Japan to discover early stages of Dz. Surgery is probably easier in the Japanese population because of lower BMIs. Better outcomes may also reflect more extensive LND performed as standard practice.
question
What surgical margin is necessary for resection of gastric cancer?
answer
>=5 cm proximal and distal margin (except for select cases removed endoscopically)
question
In what tumor location is subtotal vs. total gastrectomy indicated?
answer
Subtotal gastrectomy for distal tumors (antrum/body); total gastrectomy for proximal tumors (cardia, greater curvature)
question
Is there a benefit of advocating total gastrectomy for most gastric tumors?
answer
No. According to the following 2 trials, there is no benefit of advocating total gastrectomy: Gouzi et al (Ann Surg 1989) and Italian data (Bozzetti F et al., Ann Surg 1999)
question
Describe the results of the Gouzi et al. trial (Ann Surg 1989) comparing total gastrectomy vs. subtotal gastrectomy
answer
Gouzi et al. randomized distal tumors to total gastrectomy vs. subtotal gastrectomy. There were no differences in morbidity/mortality (1.3% vs. 3.2%) or survival outcomes (5-yr OS 48%). (Ann Surg 1989)
question
Describe the results of the Italian trial (Bozzetti F et al., Ann Surg 1999) comparing subtotal gastrectomy and total gastrectomy.
answer
Italian data from a randomized trial (Bozzetti F et al., Ann Surg 1999) showed no difference in 5-yr survival between subtotal gastrectomy (65%) and total gastrectomy (62%).
question
Should splenectomy be performed for proximal gastric tumors to get splenic LN clearance?
answer
Avoid splenectomy if possible, since there is no value of splenectomy in a randomized trial (Csendes A et al., Surgery 2002). Splenectomy and pancreatectomy had an adverse impact on survival in the Dutch and MRC D1 vs. D2 RCTs (see below).
question
How are GE junction cancers classified?
answer
GE junction cancers are classified by the Siewert classification. (3 types)
question
Describe Type I GE junction tumor based on the Siewert classification.
answer
Type I: adenocarcinoma of distal esophagus, arising from Barrett, that infiltrate GE junction (-5cm to -1 cm above GEJ)
question
Describe Type II GE junction tumor based on the Siewert classification.
answer
Type II: adenocarcinoma of cardia portion, arising from cardia and short segment of intestinal metaplasia at GE junction (-1 cm to + 2 cm below GEJ).
question
Describe Type III GE junction tumor based on the Siewert classification.
answer
Type III: adenocarcinoma of subcardial stomach, which may infiltrate GE junction or distal esophagus from below (+2 to +5 cm below GEJ))
question
Why is the Siewert classification of GE junction tumors important therapeutically?
answer
Type I has lymphatic drainage reminiscent of esophageal primaries (mediastinal and celiac), whereas types II-III drain to celiac, splenic, and para-aortic (P-A) nodes. Esophagectomy is typically recommended for type I and II tumors, whereas gastrectomy is recommended for type III tumors
question
Describe D0 nodal dissection for gastric cancer
answer
D0: no nodal dissection
question
Describe D1 nodal dissection for gastric cancer
answer
D1: perigastric nodes removed (i.e. JRS N1 nodes removed)
question
Describe D2 nodal dissection for gastric cancer
answer
D2: D1 + periarterial nodes (left gastric, hepatic, celiac, splenic) (i.e. JRS N2 nodes removed)
question
Describe D3 nodal dissection for gastric cancer
answer
D3: D2 + hepatoduodenal, peripancreatic, mesenteric root, portocaval, P-A nodes, middle colic (i.e. JRS N3 and N4 nodes removed)
question
Is extended lymphadenectomy necessary for surgical cure of gastric cancer?
answer
No. Although results from numerous randomized trials have not shown an OS advantage of extended lymphadenectomy, CSS and LRR may be improved with extended dissection in the most recent update of the Dutch trial.
question
Describe the Dutch trial (Bonenkamp JJ et al., NEJM 1999) for gastric cancer.
answer
Dutch trial (Bonenkamp JJ et al., NEJM 1999): 711 pts randomized to D1 vs. D2 dissection. There was greater mortality in the D2 group (10% vs. 4%, p = SS), and 5-yr OS was 45% vs. 47% (NSS). In the most recent 15-yr update (Songun I et al., Lancet Oncol 2010), the 15-yr OS is 21% in the D1 group and 29% in the D2 groups (p = 0.34). However, the gastric cancer-related death rate is significantly higher in the D1 group (48%) vs. the D2 group (37%), while deaths from other Dz were similar in the 2 groups. LR was lower in the D2 group (12% vs. 22%) as well as the regional recurrence (13% vs. 19%) (all SS).
question
What are the results of the MRC trial (Cushieri A et al., Br J Cancer 1999) that compared D1 vs D2 resections in gastric cancer.
answer
MRC trial (Cushieri A et al., Br J Cancer 1999): 400 pts randomized to D1 vs. D2. There was greater mortality in the D2 group (13% vs. 6.5%), and 5-yr OS was the same (35% vs. 33%).
question
What did the Dutch trial (Bonenkamp JJ et al., NEJM 1999) and the MRC trial (Cushieri A et al., Br J Cancer 1999) show in regards to a splenectomy and pancreatectomy?
answer
In both trials, splenectomy and pancreatectomy had an adverse impact on survival.
question
Describe the Japanese trial JCOG9501 (D2 vs. D2 + P-A node dissection [PAND]) (Sasako M et al., NEJM 2008) for gastric cancer.
answer
Japanese trial JCOG9501 (D2 vs. D2 + P-A node dissection [PAND]) (Sasako M et al., NEJM 2008) demonstrated that although extended LND does not increase morbidity or mortality, there is also no difference in 5-yr OS (69.2% for D2 vs. 70.3% for D2 + PAND) or for LRR.
question
Describe the Italian trial (D1 vs. D2) (Degiuli M et al., Br J Surg 2010) for gastric cancer.
answer
An Italian trial (D1 vs. D2) (Degiuli M et al., Br J Surg 2010) has shown no increased morbidity or mortality with extended lymphadenectomy, but clinical outcomes have not yet been reported.
question
What is the min # of LNs that should be pathologically assessed in a gastrectomy specimen?
answer
In the U.S., at least 15 LNs should be assessed by the pathologist, since pt survival improves if >15 LNs are examined.
question
What are the selection criteria for endoscopic mucosal resection (EMR) or limited surgical resection (without nodal evaluation) of gastric cancer?
answer
Favorable early-stage gastric cancer: Tis-T1a (not involving submucosa), small (<=3 cm), nonulcerated, well differentiated, N0. In general, these types of tumors have <5% LN met rate.
question
When is surgery alone adequate for gastric cancer?
answer
T1N0 or T2N0 (but not beyond the muscularis propria). 5-yr OS for favorable early-stage gastric cancer is 80%-90%. For all others, adj Tx is needed (Stage IB [except T2aN0] to IIIC [nonmetastatic]).
question
What is the relapse pattern after "curative" resection of gastric cancer?
answer
Distant Dz (50%) and LRR. LRR is common in the gastric bed, nearby LNs, anastomatic site, gastric remnant, and duodenal stump. In the classic paper of the University of Minnesota reoperative analysis (Gunderson L et al., IJROBP 1982), local-only recurrence was seen in 29%, LR and/or regional LN mets in 54%, and LF as any component of failure in 88% of pts.
question
What is the evidence that demonstrated the benefit of adj CRT after surgical resection for gastric cancer?
answer
INT-0116 (Macdonald JS et al., NEJM 2001): 556 pts, stage IB-IV (nonmetastatic) adenocarcinoma of stomach and GE junction (~20%), randomized after en bloc resection to -margin to (a) observation or (b) CRT (1 cycle bolus 5-FU/leukovorin [LV]) before RT, 2 cycles during 45 Gy RT, and 2 cycles after RT. Median follow-up was 5 yrs. CRT was beneficial in all parameters except for DM. 3-yr RFS 48% vs. 31%; 3-yr OS 50% vs. 41%; median OS 36 mos vs. 27 mos; and LR 19% vs. 29%. DM 18% surgery vs. 33% CRT (NSS). Toxic deaths of 1% were seen.
question
What is the major criticism for the benefit of CRT seen in INT-0116?
answer
Suboptimal LND (54% D0, 10% D2) is the major criticism of INT-0116.
question
Is there a benefit of postop CRT for pts with more extensive lymphadenectomy?
answer
Yes. There is a benefit according to a retrospective review from South Korea (Kim S et al., IJROBP 2005). In a series of 990 pts, stage II-IV with D2 resection +/- postop CRT, as done on INT-0116, postop CRT benefited all pts regardless of stage. Overall, CRT vs. surgery alone: 5-yr OS 57% vs. 51%, RFS 54.5% vs. 47.9%, and LRF 14.9% vs. 21%, respectively (all SS).
question
Is there a role for preop CRT for gastric cancer?
answer
Possibly, although no phase III studies have been published to date. However, for GE junction tumors, preop CRT based on randomized data suggests benefit (Chapter 46: Walsh TN et al., NEJM 1996). A phase II study of neoadj CRT (RTOG 9904: Ajani JA et al., JCO 2006) using induction chemo x 2 (5-FU/LV/cisplatin) → CRT (continuous infusion [CI] 5-FU/weekly Taxol) showed pCR of 26% and R0 resection of 77%.
question
Is there a role for postop RT alone for resected gastric cancer?
answer
Possibly. Although not standard practice, there are weak data suggesting LC benefit with conflicting results on survival benefit. Most adj RT-alone trials utilized IORT +/- EBRT vs. surgery-alone randomization and found benefit with adj RT.
question
Is there data to show benefit of postop chemo alone after gastric cancer resection?
answer
This is uncertain, with only 2 out of 6 randomized trials showing benefit. Most are small underpowered studies. The only good data with a large # of pts (Sakuramoto S et al., NEJM 2007) used adj S-1 (an oral fluoropyrimidine used in Japan) chemo vs. surgery alone in 529 pts, all with stage II or III gastric cancer with resection and D2 LND. S-1 had a superior 3-yr OS of 80% vs. 70% in the surgery-alone group (p = 0.002). ;;;;; Recent meta-analysis of 3,658 pts from randomized trials showed a HR 0.82 with chemo. (Gianni L et al., Ann Oncol 2001)
question
What is the recent study that demonstrated a survival benefit of periop chemo compared to surgery alone for the management of gastric cancer? What is the major weakness with this approach?
answer
MRC Adjuvant Gastric Cancer Infusional Chemo (MAGIC) trial (Cunningham D et al., NEJM 2006): 503 pts with gastric, GE junction, and distal esophageal adenocarcinoma (26%) randomized to (a) preop epirubicin/cisplatin/5-FU (ECF) x 3 and postop ECF x 3 or (b) surgery alone showed a survival benefit for chemo. 5-yr OS was 36% vs. 23%, respectively (p = 0.009). The major weakness of the MAGIC trial is that the pCR rate was 0%.
question
What is the current U.S. randomized trial in resected high-risk gastric cancer?
answer
CALGB 80101, pts with completed resected, high-risk gastric cancer randomized to (a) the modified Macdonald regimen (5-FU/LV x 1 → CI 5-FU x 2 +RT → 2 cycles 5-FU/LV) or (b) ECF (epirubicin 50 mg/m2, cisplatin 60 mg/m2, and CI 5-FU 200 mg/m2/day x 21 days) x1 → RT + CI 5-FU x 2 → ECF x 2 cycles.
question
What is the survival of pts with locally advanced unresectable gastric cancer? How are these pts managed?
answer
5-yr OS is generally 5%-20%. In most randomized studies of these pts, CRT has benefit over chemo alone (5-yr OS 12%-18% vs. 0%-7%). GITSG G274 (Schein PS et al., Cancer 1982) used CRT (50 Gy) vs. chemo alone (5-FU/1-(2-chloroethyl)-3-(4-methylcyclohexyl)-1-nitrosourea [MeCCNU]). There was better survival with CRT (18% vs. 7%).
question
For metastatic gastric cancer pts, what are the palliative Tx for the incurable pt?
answer
Surgical resection for carefully select pts with good performance status with Sx of obstruction or hemorrhage is better for palliation than stents or bypass. RT alone or CRT can be considered for the nonsurgical candidate (short course pallation 30 Gy/10 fx, 37.5 Gy/15 fx). Endoluminal laser ablation can be used for proximal lesions with esophageal obstruction → chemo. Palliative chemo compared to best supportive care has an overall HR of 0.39, and MS increases from 4.3 mos to 11 mos based on Cochrane meta-analysis (Wagner A et al., Cochrane Database Sys Rev 2006).
question
For the metastatic gastric cancer pt with bleeding or pain from the primary Dz, what are adequate palliative RT doses?
answer
Bleeding: 30 Gy in 10 fx may be sufficient; however, for the initial few doses, a higher fractional dose (4-4.5 Gy) may be better for bleeding control. After 3-4 fx, the practitioner can back down to 3 Gy/fx. ;;;;; Pain from tumor invasion: 45 Gy may be necessary.
question
What is the irradiation volume and dose of postop CRT after gastric tumor resection?
answer
Tumor bed and nodal volumes constructed with preop/postop imaging and surgical clip placement. In general, node+ Dz requires wide coverage of the tumor bed, remaining stomach, all resection/anastomotic sites, and nodal drainage areas (which is dependent on tumor location). Use 45 Gy to the initial volume, then CD to 50.4 Gy to the surgical bed or at-risk areas. Pre-Tx J-tube placement (at time of staging laparoscopy) is helpful for nutritional support.
question
When would it be optional to treat the nodal beds in a resected gastric cancer?
answer
Tx would be optional for pts with negative nodes, pts having had adequate surgery and pathologic evaluation for nodes (>10-15 nodes), and wide surgical margins (at least 5 cm).
question
What are the at-risk regional nodal sites for GE junction tumors?
answer
1. GE junction: mediastinal, periesophageal, celiac, perigastric
question
What are the at-risk regional nodal sites for proximal stomach tumors?
answer
2. Proximal stomach: perigastric, periesophageal, celiac, pancreaticoduodenal, porta hepatis
question
What are the at-risk regional nodal sites for gastric body tumors?
answer
3. Body: perigastric, splenic, celiac, peripancreatic, porta hepatis
question
What are the at-risk regional nodal sites for distal stomach tumors?
answer
4. Distal stomach: perigastric, periduodenal, peri-pancreatic, porta hepatis, celiac
question
How does the target volume differ for proximal vs. distal gastric lesions?
answer
Proximal lesions: include splenic hilum and left medial diaphragm in the target volume, but inf extent does not need to go to L3 (may just go to L1-2 coverage of the superior mesenteric artery/P-A nodes) ;;;;; Distal lesions: include 1st portion of the duodenal C-loop but not the splenic hilum ;;;;; For proximal and distal lesions and -nodes with adequate dissection, the remnant of the stomach does not need to be covered. For body lesions, however, the gastric remnant needs to be covered in all cases.
question
What is the preferred technique for Tx planning of postop CRT?
answer
3D-CRT (4 field) or IMRT can spare normal tissue and reduce toxicity better than traditional AP/PA fields, but greater conformality requires a more careful delineation of Tx targets.
question
What are some long-term complications of gastrectomy?
answer
Dumping syndrome (diarrhea, cramping, palpitations, reactive hypoglycemia) and malabsorption (B12, iron, calcium; supplement if necessary)
question
What is done during follow-up of pts treated with surgery and adj therapies?
answer
Surgery and adj therapy follow-up: H&P every 4-6 mos x 3 yrs, then annually; CBC/CMP, endoscopy, and radiologic imaging as clinically indicated; and monitor for B12 deficiency (NCCN 2010 )
question
In treating the postgastrectomy pt with adj CRT, what is the dose limit to the remnant of stomach?
answer
Remnant of stomach: 45 Gy
question
In treating the postgastrectomy pt with adj CRT, what is the dose limit to the kidney?
answer
Kidney: V18 <30%
question
In treating the postgastrectomy pt with adj CRT, what is the dose limit to the liver?
answer
Liver: V30 <50%-70%
question
In treating the postgastrectomy pt with adj CRT, what is the dose limit to the heart?
answer
Heart: If RT alone → V40 <50%, CRT for heart → V40 <40%
question
In treating the postgastrectomy pt with adj CRT, what is the dose limit to the spinal cord?
answer
Spinal cord: <=45 Gy
Get an explanation on any task
Get unstuck with the help of our AI assistant in seconds
New