784 ABSTRACTS

156. Age-specific survival for the four most prevalent malignancies

among the elderly

M. Kiderlen1, E. Bastiaannet1, W. van de Water1, A.J.M. de Craen2,

C.B.M. van den Broek1, M.A.G. Elferink3, L. de Munck3,

R. Damhuis4, C.J.H. van de Velde1, G.J. Liefers1

1 Leiden University Medical Center, Surgery, Leiden, The Netherlands2 Leiden University Medical Center, Gerontology & Geriatrics, Leiden,

The Netherlands3 Comprehensive Cancer Centre the Netherlands, Utrecht, The Netherlands4 Comprehensive Cancer Centre the Netherlands, Rotterdam, The

Netherlands

Background: The four most prevalent malignancies among the elderly

are breast, colon, rectal and prostate cancer. Aims of this study were to es-

timate mortality due to cancer and other causes, to assess relative survival

in an unselected population of Dutch cancer patients, and to observe age-

specific variation in relative survival.

Material and methods: From the Netherlands Cancer Registry (NCR)

database, all patients with a first primary invasive breast (females), colon,

rectal or prostate cancer diagnosed between 1996 and 2008 were selected.

Age was categorized as <65, 65-69, 70-74, 75-79, 80-84 and �85 years at

diagnosis. Primary endpoint was relative survival, which was calculated as

the ratio of observed survival among the patients and expected survival

based on the general population of corresponding age, sex and year of di-

agnosis. Relative Excess Risks of death (RER) were estimated using a mul-

tivariable generalized linear model with a Poisson distribution, based on

collapsed relative survival data, using exact survival times. Multivariable

analyses were adjusted for year of diagnosis, sex, stage, surgery, radiother-

apy, chemotherapy and systemic treatment). Mortality in the cohort was

compared to the overall mortality in the matched Dutch general population

to calculate the relative mortality in the specific age groups.

Results: Overall, 142,677 breast, 74,940 colon, 40,691 rectal and

94,020 prostate cancer patients were included. The estimated proportion

of mortality due to cancer decreased with age for all four malignancies,

with lowest cancer related mortality rates for breast and prostate cancer pa-

tients (table 1). However, relative survival decreased with increasing age

(multivariable p<0.001 in all four malignancies).

Conclusions: Even though the proportion of mortality due to cancer

decreased with age, relative survival of patients diagnosed with the four

most prevalent malignancies decreased as patients get older. Reasons for

this decreased survival are yet unexplained, but probably related to treat-

ment (over- or under treatment) and patient characteristics.

Table 1

Estimated proportion of deaths due to the cancer or due to other causes.

Estimated % within

deceased patients

<65 65-69 70-74 75-79 80-84 �85

Breast Cancer (%) 89 57 47 49 40 28

Other causes (%) 11 43 53 51 60 72

Colon Cancer (%) 95 80 71 64 59 59

Other causes (%) 5 20 29 36 41 41

Rectal Cancer (%) 95 76 70 64 60 58

Other causes (%) 5 24 30 36 40 42

Prostate Cancer (%) 84 41 35 34 35 43

Other causes (%) 16 59 65 66 65 57

157. Determinants of decision making for curative surgery and survival

in patients with resectable esophageal cancer in the Netherlands e A

population-based study

M. Ko€eter1, L.N. van Steenbergen2, V.E. Lemmens2, G.A.P.

Nieuwenhuijzen1

1 Catharina Hospital, Cancer Centre, Eindhoven, The Netherlands2 Eindhoven Cancer Registry, Research, Eindhoven, The Netherlands

Background: According to the Dutch guidelines the preferred treat-

ment for resectable esophageal cancer is surgery with or without

neoadjuvant chemoradiation. Esophageal surgery has a high morbidity

and potential mortality, especially for the elderly and patients with multi-

ple comorbidities. Hence, some patients are regarded as not eligible for

surgery and are therefore not offered potential curative treatment. The ob-

jective is to examine determinants of decision making for surgery and fac-

tors affecting survival in resectable esophageal cancer from a population

based in the Netherlands.

Materials and methods: All patients with resectable (T1-3, N0-3, M0-

1A) esophageal cancer (n¼849) between 2003 and 2010 were selected

from the population-based data from the Eindhoven Cancer Registry. Lo-

gistic regression analysis was conducted to examine determinants of sur-

gery including gender, age, comorbidity, T stage, histology, tumour

location, and socioeconomic status (SES). Furthermore, overall survival

and determinants of survival were examined using multivariate Cox regres-

sion analysis.

Results: Forty-five percent of patients with resectable esophageal can-

cer underwent surgery. These patients were significantly younger than pa-

tient who did not underwent surgery (63 vs. 71 years).

Multivariate logistic regression analysis showed that age �70 years

(OR 0.4; CI 0.2-0.4), low SES (OR 0.5; CI 0.4-0.8), two or more comor-

bidities (OR 0.4; CI 0.2-0.6), and squamous-cell carcinoma (OR 0.6; CI

0.4-0.9) were significantly less often offered a potential curative

resection.

Multivariate Cox regression of these factors showed that only surgery

(HR 0.5; CI 0.4-0.6) was associated with better overall survival (OS) and

that higher tumour stage and lower tumour differentiation was associated

with worse OS. All other factors did not influence OS. OS for surgery ver-

sus no surgery showed a 1, 3 and 5 years survival of respectively 80% vs.

45%, 47% vs. 15% and 33% vs. 12% (log rank; p<0.001).

Conclusion: Age (�70 years), SES (low), comorbidity (2 or more),

histology (squamous-cell) and tumour location (proximal) seem to play

a role in decision making for curative surgery in patients with resectable

esophageal cancer, however do not influence OS. Surgery is the most im-

portant factor for overall survival as well as tumour differentiation and

stage. Therefore, the decision to conduct surgery in these patients is of cru-

cial importance.

158. Validity of the combination treatment of the surgery and

chemotherapy in advanced gastric cancer

Y. Imamura3, M. Kanou1, K. Ishida2, H. Tokumo2, H. Komatsu2

1 JA Hiroshima General Hospital, Surgery, Hatsukaichi-city Hioshima,

Japan2 JA Hiroshima General Hospital, Gastroenterology, Hatsukaichi-city

Hioshima, Japan3 JA Hiroshima General Hospital, Surgery and Chemotherapy Director,

Hatsukaichi-city Hioshima, Japan

Background: While surgery and appropriate adjuvant chemotherapy

have resulted in superior stage-by-stage survival in Japan, the prognosis

of stage IV advanced gastric cancer remains unsatisfied. Phase III trials

conducted in Japan for unresectable or recurrent gastric cancer have em-

phasized the utilities of the S1 monotherapy and a combination of S1

and CDDP, other combination therapies. Therefore, the purpose of this

study reveals how combination of an operation and antineoplastic drug

medical treatment should be performed for the purpose of long-term sur-

vival in a bad prognosis’s stage advance cancer case.

Material and methods:We studied 105 patients diagnosed as the clin-

ical stage IV (UICC TMN classification) in the period from January, 2008

to December, 2010 by the medical treatment patient in our hospital. Over-

all survival time was defined as the interval from the date of registration to

the date of death. The survival curves were estimated by the KaplaneMe-

ier method, and differences were analyzed with the stratified log-rank test.

Hazard ratios for various prognostic factors were calculated using a strati-

fied Cox proportional hazards model.

Results: 1) Patients characteristic: The patients were 74 males and 31

females, and their median age was 72 at the range of 28-93. The character

of tumor histology included 67 diffuse type, 31 intestinal type and 7 other.