Kattan et al validated a nomogram for predicting postoperative recurrence within 84 months (7 years) in a patient with a localized prostate carcinoma treated by radical prostatectomy. This can help identify patients who may benefit from additional therapeutic interventions. The authors are from Memorial Sloan Kettering Cancer Center in New York and Baylor College of Medicine in Houston.
Parameters for score:
(1) preoperative PSA in ng/mL
(2) Gleason score (sum of 2 highest Gleason grades)
(3) prostate capsule invasion
(4) surgical margins
(5) seminal vesicle involvement
(6) lymph nodes
|
Parameter |
Finding |
Points |
|---|---|---|
|
lymph node metastases |
absent |
0 |
|
|
present |
28 |
|
seminal vesicle involvement |
absent |
0 |
|
|
present |
24 |
|
surgical margins |
negative |
0 |
|
|
positive |
33 |
|
prostate capsule |
not involved |
0 |
|
|
into capsule |
30 |
|
|
focally through |
51 |
|
|
established |
56 |
|
Gleason score |
3 |
1.2 |
|
|
4 |
0.6 |
|
|
5 |
0 |
|
|
6 |
5 |
|
|
7 |
30 |
|
|
8 |
46 |
|
|
9 |
59 |
|
|
10 |
72 |
NOTE: A Gleason score of 5 is assigned fewer points than a Gleason score 3 or 4.
|
Preoperative PSA in ng/mL |
Points |
|---|---|
|
0.1 |
0 |
|
0.2 |
15 |
|
0.3 |
24 |
|
0.4 |
30 |
|
0.5 |
35 |
|
0.6 |
39 |
|
0.7 |
42 |
|
0.8 |
45 |
|
0.9 |
48 |
|
1 |
50 |
|
2 |
65 |
|
3 |
74 |
|
4 |
78 |
|
5 |
82 |
|
6 |
84 |
|
7 |
87 |
|
8 |
89 |
|
9 |
91 |
|
10 |
93 |
|
100 |
100 |
If this data is analyzed in JMP, the following equation can be used to reasonably approximate the data:
points for preoperative PSA =
= (20.104044 * (LN(PSA))) + 48.663173
|
Total Number of Points |
Probability of 84 Month Recurrence Free Period |
Probability of Recurrence in 84 Months |
|---|---|---|
|
70 |
99% |
1% |
|
90 |
98% |
2% |
|
116 |
95% |
5% |
|
138 |
90% |
10% |
|
159 |
80% |
20% |
|
173 |
70% |
30% |
|
191 |
50% |
50% |
|
207 |
30% |
70% |
|
226 |
10% |
90% |
|
246 |
1% |
99% |
This gives a sigmoid curve with the central point at 191 points. This can be divided into 2 curves which can be approximated in JMP.
For points below 191:
probability of recurrence in 84 months as a decimal fraction =
= 0.01 * ((0.0000383 * ((total points)^3)) – (0.010177 * ((total points)^2)) + (0.964169 * (total points)) – 29.90878)
For points >= 191:
probability of recurrence in 84 months as a decimal fraction =
= 0.01 * ((-0.01121 * ((total points)^2)) + (5.802097 * (total points)) – 649.6667)
probability of being recurrence free at 84 months =
= 1.00 – (probability of recurrence)
Specialty: Hematology Oncology, Surgery, general, Urology
