Segelman et al developed 2 models for predicting metachronous peritoneal carcinomatosis associated with colorectal cancer. One model was for colon cancer and the second was for rectal cancer. The authors are from Karolinska Institutet and Danderyd Hospital in Stockholm.
Patient selection: rectal carcinoma
Outcome: metachronous peritoneal carcinomatosis
Parameters:
(1) age in years
(2) pathologic T stage (pT)
(3) pathologic N stage (pN)
(4) number of examined lymph nodes
(5) completeness of colon resection (R0, R1, R2)
(6) preoperative radiotherapy
(7) adjuvant chemotherapy
Parameter |
Finding |
Points |
age |
|
(-0.03 * ((age) - 70) |
pT |
pT0 to pT2 |
0 |
|
pT3 |
1.22 |
|
pT4 |
1.86 |
pN |
pN0 |
0 |
|
pN1 |
0.88 |
|
pN2 |
1.46 |
number of lymph nodes |
0 to 11 |
0.61 |
|
>= 12 |
0 |
completeness of resection |
R0 |
0 |
|
R1 |
1.35 |
|
R2 |
1.42 |
preoperative radioatherapy |
no |
0 |
|
yes |
-1.03 |
adjuvant chemotherapy |
no |
0 |
|
yes |
-0.19 |
total score =
= SUM(points for all of the parameters)
Interpretation:
• minimum score: around -2 (depends on age)
• maximum score: around 6.5 (depends on age)
• The higher the score the greater the risk of peritoneal carcinomatosis.
Score |
3-Year Probability of Metachronous Pertinoneal Carcinomatosis |
0 |
4.3 |
0.5 |
6.8 |
1.0 |
11.1 |
1.5 |
17.6 |
2.0 |
27.1 |
2.5 |
40.3 |
3.0 |
54.4 |
5.0 |
79.4 |
The data from 0 to 3is approximated by the equation
probability =
= (5.1667 * ((score)^2)) + (1.1643 * (score)) + 4.5476
Specialty: Hematology Oncology