Role of radiation therapy in gastric adenocarcinoma

Table 1 Patterns of relapse based on University of Minnesota re-operation series and autopsy series

	Univ. of Minnesota	Autopsy series[6-9]
	Re-operation
	series[10] (n=107)
Pattern of relapse	%	%
Gastric bed	55	52-68
Anastomosis	27	54-60
Abdominal wound	5	-
Peritoneal seeding	42	30-43
Lymph nodes	431	52
Local-regional as any site	69	80-93
Local-regional only	23	-
Lymph Nodes only	7	-
Lymph nodes only in nodal	3	-
dissection sites
Distant metastases	36	50

¹Most common nodal sites of relapse were porta-hepatis, celiac, and para-aortic regions. Other sites were suprapancreatic, pancreaticoduodenal, and splenic hilar regions.

Table 2 Randomized trials of adjuvant radiation therapy in gastric carcinoma

		Survival		Local-regional relapse
Reference	n	Median (mo)	5-year (%)	P value	%	P value
Mayo Clinic[14]
Surgery alone	23	15	4	0.05	54	NS
Post-op EBRT + CT	39	24	23		39
British stomach group[11,12]
Surgery alone	145	15	20	NS	27	<0.01 for
Post-op CT	138	13	19		19
Post-op EBRT	153	17	12		10	EBRT
China-Beijing[13]
Surgery alone	199	NR	20	0.009	521	<0.025
Pre-op EBRT	171	NR	30		39
Intergroup 0116[16]
Surgery alone	275	27	41 (3 yr)	0.005	29	NR
Postop EBRT + CT	281	36	50 (3 yr)		19
Walsh et al[15]
Surgery alone	55	11	6 (3 yr)	0.01	NR	-
Preop EBRT + CT	58	16	32 (3 yr)

Abbreviations: CT = chemotherapy, EBRT = external beam radiation therapy, NS = not significant, NR = not reported.

¹Refers to local relapse. Regional relapse with 54% with surgery alone versus 39% with chemoradiation, P < 0.05.

Table 3 Randomized trials of D1 versus D2 lymph node dissection in gastric cancer

	MRC[18] (n=711)		Dutch[17] (n=400)
Endpoint	D1	D2	P value	D1	D2	P value
5 year overall survival	45%	47%	NS	35%	33%	NS
Post-operative morbidity	25%	43%	<0.001	28%	46%	<0.001
Post-operative mortality	4%	10%	0.004	6.5%	13%	0.04

Abbreviations: NS = non-significant.

Table 4 Prospective trials of pre-operative chemoradiation in gastric cancer

RT dose Overall Median Complete Partial R0 % Distant
Reference Chemo (Gy) survival % survival time response (%) response (%) rate (%) metastases
(2 yr) (mo) during therapy
RTOG	5FU/LV/cis×2 prior to RT;
99-04[46]	5FU with RT	45	NR	NR	27	NR	77	NR
(n = 49)
Roth[45]		31.2,
(n = 19)	Cis/5FU	38.4,	71	NR	5	50	NR	0
		45.61
Lowy[41]
(n = 23)	5FU	45	NR	NR	11	63	NR	17
Ajani 2004[43]
(n = 33)	5FU/LV/cis×2 prior to RT; 5FU with RT	45	54	33.7	30	24	NR	12
Ajani 2005[44]
(n = 41)	5FU/cis/tax×2 prior to RT; 5FU/tax with RT	45	682	Not reached	20	153	78	0
Balandraud[47]
(n = 42)	5FU/cis	45	45.6	23	14	-	81	-
Klautke[67]
(n = 21)	Cis/5FU or tax	50.4	42	18	14	62	53	-

Abbreviations: Cis = cisplatin, 5FU = 5-fluorouracil, LV = leucovorin, tax = paclitaxol, RT = radiation therapy, R0 = resection with negative margins.

¹Given 1.2 Gy b.i.d. in a phase I dose escalation trial;

²At a median follow-up of 36 mo;

³PR defined as <10% residual cells in resected specimen.

Table 5 Treatment results: Unresectable or residual gastric cancer

Reference	n	Treatment	Radiation therapy	Chemotherapy	Results
Randomized
Mayo Clinic[51]	48	EBRT ± CT	35-37.5 Gy in 4-5 wk	5FU 1st wk of EBRT	Median survival 13 vs 6 mo and 5-year overall survival 12% vs 0% favoringEBRT+5FU
GITSG[53]	90	CT ± EBRT	50 Gy split course in 8 wk	5FU during EBRT, maintenance 5FU/MeCCNU	4-year survival 18% vs 7%, favoring CT+EBRT
EORTC[52]	90	EBRT ± CT	55.5 Gy in 6 wk	5FU	14% long-term survival (3 patients) with EBRT and 5FU
Retrospective
MGH[55]	32	EBRT ± CT	45-55 Gy in 5-6 wk	5FU during EBRT, maintenance 5FU/MeCCNU	EBRT+CT: Unresectable disease 14 mo median survival; unresectable and residual disease 10% 4-year survival

Abbreviations: EBRT=external beam radiation therapy; CT = chemotherapy; 5FU = 5-fluorouracil; MeCCNU = semustine; GITSG = gastrointestinal study group; EORTC=European organization for research and treatment of cancer; MGH=Massachusetts General Hospital; Gy=gray.