Background
Methods
Clinical data retrieval
Study design
-
Seventy-eight patients diagnosed with SCC of the anal canal underwent chemoradiation.
-
Three months after the end of treatment, all 78 patients made the first evaluation of local response with standard anoscopy, digital rectal examination, and clinical examination of the inguinal region. The objective was to identify if any patient was presenting a lesion progression.
-
Six months after the end of treatment, all 78 patients underwent a new evaluation with computer tomography (CT) of the chest, magnetic resonance imaging (MRI) of the abdomen and pelvic, digital rectal examination, high-resolution anoscopy, and clinical examination of the inguinal region. Those who were suspected of a residual lesion underwent a new biopsy to confirm histopathological suspicion of the residual lesion.
-
Patients who had residual lesions confirmed by biopsy were referred for surgical treatment.
-
The results of the HPV, HIV, TP53 and p16 analyses of all 78 patients were only known after 6 months of treatment (blind to those who evaluated the response and to those who did the molecular analyses).
Analysis of the clinical response
Pathology review
DNA extraction
HPV analysis by direct sequencing
HIV detection
TP53 mutation analysis by nucleotide sequencing
Fluorescent in situ hybridization
Western blotting
Statistical analysis
Results
Study population
Mutational status and TP53 copy number and p16 protein expression analyses
Characteristics | N | % |
HPV Positive
N (%)
|
HPV Negative
N (%)
| p-value |
---|---|---|---|---|---|
Age |
0.361
| ||||
< 65 years old | 44 | 56.4% | |||
≥ 65 years old | 34 | 43.6% |
35 (59.3)
|
9 (47.4)
| |
Gender |
24 (40.7)
|
10 (52.6)
|
0.004
| ||
Female | 64 | 82.1 | |||
Male | 14 | 17.9 |
53 (89.8)
|
11 (57.9)
| |
Degree of Cellular Differentiation |
6 (10.2)
|
8 (42.1)
|
0.351
| ||
G I | 6 | 7.7 | |||
G II | 58 | 74.4 |
6 (10.2)
|
0 (0)
| |
G III | 11 | 14.1 |
42 (71.2)
|
16 (84.2)
| |
G IV | 3 | 3.8 |
8 (13.6)
|
3 (15.8)
| |
Clinical Stage (UICC) |
3 (5.1)
|
0 (0)
|
0.031
| ||
I | 5 | 6.4 | |||
II | 47 | 60.3 |
5 (8.5)
|
0 (0)
| |
IIIA | 16 | 20.5 |
39 (66.1)
|
8 (42.1)
| |
IIIB | 10 | 12.8 |
8 (13.6)
|
8 (42.1)
| |
N Stage |
7 (11.9)
|
3 (15.8)
|
0.354
| ||
Negative | 60 | 76.9 | |||
Positive | 18 | 23.1 |
47 (79.7)
|
13 (68.4)
| |
T Stage |
12 (20.3)
|
6 (31.6)
|
0,012
| ||
T1 (≤ 2 cm) | 6 | 7.7 | |||
T2 (> 2 and ≤5 cm) | 30 | 38.5 |
6 (10.2)
|
0 (0)
| |
T3 (> 5 cm) | 30 | 38.5 |
27 (45.8)
|
3 (15.8)
| |
T4 (tumour invading adjacent organ) | 12 | 15.4 |
20 (33.9)
|
10 (52.6)
| |
HPV |
6 (10.2)
|
6 (31.6)
|
NA
| ||
16 | 49 | 62.8 | |||
18 | 10 | 12.8 |
49 (62.8)
|
0 (0)
| |
Negative | 19 | 24.4 |
10 (12.8)
|
0 (0)
| |
HIV
|
19 (24.4)
|
0 (0)
|
1.000
| ||
Positive | 19 | 24.4 | |||
Negative | 59 | 75.6 |
14 (23.7)
|
5 (26.3)
| |
P16 |
45 (76.3)
|
14 (73.7)
|
< 0.001
| ||
Positive | 57 | 73.1 | |||
Negative | 19 | 24.4 |
57 (96.6)
|
0 (0)
| |
Borderline | 2 | 2.6 |
0 (0)
|
19 (100.0)
| |
Clinical response at 6 months |
2 (3.4)
|
0 (0)
|
< 0.001
| ||
Yes | 47 | 60.3 | |||
No | 31 | 39.7 |
47 (79.7)
|
0 (0)
| |
TP53
|
12 (20.3)
|
19 (100.0)
|
< 0.001
| ||
Mutated | 21 | 26.9 | |||
Wild type | 57 | 73.1 |
2 (3.4)
|
19 (100.0)
| |
Total | 78 | 100.0 |
57 (96.6)
|
0 (0)
|
HPV negative /p16 negative | FISH chromosome 17/ gene TP53 (%) | ||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|
Case | Protein Change | Functional Consequence | Exon |
2/2
|
2/1
|
1/1
|
3/2
|
3/1
|
3/3
|
4/2
|
4/1
|
6 | R282W | Non-functional | 8 | 60.5 | 28.0 | 10.0 | 1.5 | – | – | – | – |
7 | R181L | Partially functional | 5 | 52.5 | 43.0 | 4.5 | – | – | – | – | – |
11 | R273H | Non-functional | 8 | 69.0 | 23.0 | 4.5 | 3.5 | – | – | – | – |
16 | G245S | Non-functional | 7 | 67.5 | 28.5 | 2.0 | 2.0 | – | – | – | – |
19 | R273H | Non-functional | 8 | 70.0 | 24.5 | 4.0 | 1.5 | – | – | – | – |
23 | R175P | Non-functional | 5 | 72.0 | 20.0 | 6.0 | 2.0 | – | – | ||
31 | R175H | Non-functional | 5 | 67.0 | 23.0 | 7.0 | 3.0 | – | – | – | – |
34 | G245D | Non-functional | 7 | 64.5 | 20.5 | 10.0 | 3.0 | 2.0 | – | – | – |
49 | R181C | Partially functional | 5 | 48.0 | 44.0 | 8.0 | – | – | – | – | – |
50 | R181H | Partially functional | 5 | 44.5 | 49.5 | 6.0 | – | – | – | – | – |
59 | R213Q | Non-functional | 6 | 64.0 | 26.0 | 6.5 | 3.5 | – | – | – | – |
60 | R248W | Non-functional | 7 | 76.5 | 15.0 | 7.5 | 0.5 | 0.5 | – | – | – |
63 | R175H | Non-functional | 5 | 68.0 | 22.5 | 5.5 | 4.0 | – | – | – | – |
64 | C277F | Non-functional | 8 | 63.4 | 17.0 | 8.0 | 4.2 | 4.2 | 1.6 | 1.6 | – |
70 | R273C | Non-functional | 8 | 63.0 | 19.0 | 7.5 | 7.5 | 2.0 | 1.0 | – | – |
72 | R248Q | Non-functional | 7 | 65.0 | 17.5 | 9.5 | 4.0 | 1.5 | 1.5 | 1.0 | – |
75 | R248Q | Non-functional | 7 | 67.0 | 18.5 | 7.5 | 3.0 | 1.5 | 1.5 | 1.0 | – |
76 | R213Q | Non-functional | 6 | 65.0 | 25.5 | 5.5 | 4.0 | – | – | – | – |
77 | R273C | Non-functional | 8 | 62.7 | 24.3 | 2.7 | 5.5 | 2.7 | 1.6 | 0.5 | – |
HPV positive/p16 borderline |
2/2
|
2/1
|
1/1
|
3/2
|
3/1
|
3/3
|
4/2
|
4/1
| |||
29 | G245S | Non-functional | 7 | 54.0 | 24.0 | 1.5 | 5.0 | 5.5 | 2.5 | 6.0 | 1.5 |
57 | R181H | Partially functional | 5 | 59.0 | 23.0 | 10.5 | 1.5 | 2.0 | 1.0 | 1.5 | 1.5 |
Factors correlated to the clinical response
Characteristics | Clinical response (%) | No clinical response (%) | p-value |
---|---|---|---|
Age |
0.488
| ||
< 65 years old | 28 (63.6) | 16 (36.4) | |
≥ 65 years old | 19 (55.9) | 15 (44.1) | |
Gender |
< 0.001
| ||
Female | 46 (71.9) | 18 (28.1) | |
Male | 1 (7.1) | 13 (92.9) | |
Degree of Cell Differentiation |
0.387
| ||
G I / G II | 40 (62.5) | 24 (37.5) | |
G III / G IV | 7 (50.0) | 7 (50.0) | |
Clinical Stage (UICC) |
< 0.001
| ||
I - II | 31 (86.1) | 5 (13.9) | |
III A - III B | 16 (38.1) | 26 (61.9) | |
T stage |
< 0.001
| ||
T 1 (≤2 cm) | 1 (16.7) | 5 (83.3) | |
T 2 (> 2 and ≤5 cm) | 4 (13.3) | 26 (86.7) | |
T 3 (> 5 cm) | 15 (50.0) | 15 (50.0) | |
T 4 (tumour invading adjacent organ) | 11 (91.7) | 1 (8.3) | |
N stage |
0.035
| ||
Negative | 40 (66.7) | 20 (33.3) | |
Positive | 7 (38.9) | 11 (61.1) | |
HPV |
< 0.001
| ||
Positive | 47 (79.7) | 12 (20.3) | |
Negative | 0 (0.0) | 19 (100.0) | |
HIV |
0.063
| ||
Positive | 8 (42.1) | 11 (57.9) | |
Negative | 39 (66.1) | 20 (33.9) | |
P16 |
< 0.001
| ||
Positive | 45 (78.9) | 12 (21.1) | |
Negative/borderline | 2 (9.5) | 19 (90.5) | |
TP53
|
< 0.001
| ||
Mutant | 2 (9.5) | 19 (90.5) | |
Wild type | 45 (78.9) | 12 (21.1) |
Characteristics | OR | 95% CI |
p
| aOR | 95% CI |
p
|
---|---|---|---|---|---|---|
HPV positive | 31.1 | 1.8–531.1 |
0.018
| 31.1 | 1.8–531.1 |
0.018
|
Female gender | 10.1 | 1.4–73.0 |
0.022
| |||
P16 positive | 8.3 | 2.0–34.2 |
0.003
| |||
Age < 65 years | 1.1 | 0.6–2.0 | 0.662 | |||
Degree of cell differentiation I and II | 1.3 | 0.6–2.5 | 0.586 | |||
Clinical stage I and II | 2.5 | 1.3–5.0 |
0.008
| |||
T 2/3 | 1.2 | 0.5–3.1 | 0.675 | |||
TP53 mutated | 0.1 | 0.03–0.5 |
0.003
|