Results

The study was equally divided into two groups, consisting of 25 cases of BPH and 25 cases of prostate adenocarcinoma. Patients with prostate adenocarcinoma presented at an older age compared to those with BPH. The age of patients with BPH ranged from 40 to 98 years, with a mean age of 69 years, whereas the age of patients with prostate adenocarcinoma ranged from 52 to 91 years, with a mean age of 71.5 years. Serum PSA levels in prostate adenocarcinoma showed a wide variation, ranging from a minimum of 10.3 ng/mL to a maximum of 96.4 ng/mL (reference range of serum PSA used was from 10 ng/mL to 100 ng/mL).

The distribution of Gleason scores among cases of prostate adenocarcinoma (n=25) demonstrated marked heterogeneity, with a predominance of Gleason score 7 observed in 12 cases (48%). Within this group, the most frequent pattern was 4+3, seen in seven cases, followed by the 3+4 pattern in five cases. Gleason score 8 was identified in six cases (24%), comprising three cases with a 3+5 pattern, two cases with a 4+4 pattern, and one case with a 5+3 pattern. Gleason score 9 was noted in four cases (16%), with equal distribution between the 4+5 and 5+4 patterns, with two cases each. Gleason score 10 was observed in two cases (8%), both exhibiting a 5+5 pattern. A single case (4%) demonstrated Gleason score 6 with a 3+3 pattern.

The analysis of the relationship between serum PSA levels and Gleason grade group revealed no statistically significant association. The distribution of PSA categories across grade groups was variable without a clear linear progression; for instance, while the highest PSA level (80.1+) was present in both Grade group 2 and Grade group 4 tumors, it was absent in Grade group 5.

Distribution of p53 expression in prostate adenocarcinoma and BPH

The comparative analysis of p53 protein expression in prostate adenocarcinoma and BPH reveals a predominance of high immunoreactivity in both conditions, though with notable differences in distribution across lower categories (Table 1). In prostate adenocarcinoma (n=25), most cases (76%, n=19) exhibited strong (3+) p53 expression due to increased epithelial turnover associated with BPH and chronic low-grade inflammation rather than malignant transformation alone, followed by 20% (n=5) with moderate (2+) staining, and only a single case (4%) showing complete negativity (0%) (Figure 1). In contrast, BPH samples (n=25) demonstrated an even higher frequency of strong (3+) expression at 80% (n=20), with the remaining cases distributed between moderate 2+ expression (12%, n=3) and low 1+ expression (8%, n=2).

p53 expression | Prostate adenocarcinoma | BPH
0 (0) | 4% | 0%
1+ (<10) | 0% | 8%
2+ (10-33) | 20% | 12%
3+ (>33) | 76% | 80%

Figure 1: Photomicrograph showing high expression of p53 nuclear positivity in prostate adenocarcinoma (IHC-40X)IHC: immunohistochemistry

Distribution of Ki67 proliferation index in prostate adenocarcinoma and BPH

A comparative analysis of Ki67 proliferation index in prostate adenocarcinoma and BPH demonstrated a significant difference in proliferative activity between malignant and benign prostatic tissues (Table 2). In prostate adenocarcinoma (n=25), most cases (76%, n=19) exhibited proliferative activity, whereas BPH samples (n=25) showed almost no proliferative activity, with most cases (88%, n=22) falling into the negative category (Figure 2).

Ki67 expression | Prostate adenocarcinoma | BPH
Negative (<2) | 24% | 88%
1+(2-25) | 76% | 12%
2+(26-50) | 0% | 0%
3+(51-75) | 0% | 0%
4+(76-100) | 4% | 0%

Figure 2: Photomicrograph showing high expression of Ki67 nuclear positivity in prostate adenocarcinoma (IHC-40X)IHC: immunohistochemistry

The mean p53 expression was slightly higher in prostate adenocarcinoma (48±21.01) compared to BPH (45.6±19.91); however, this difference was not statistically significant (Mann-Whitney U=297.50, p=0.779). However, Ki-67 expression was markedly higher in prostate adenocarcinoma (10.68±18.06) than in BPH (0.56±0.72), and this difference was found to be statistically significant (Mann-Whitney U=68.50, p=0.0001).

Association between p53 expression and Gleason grade group

An analysis of p53 expression in relation to the Gleason grade group revealed a notable, though not statistically significant, trend. Higher grade groups (Grades 3, 4, and 5) were predominantly associated with high p53 expression (3+), comprising 85.7%, 100%, and 66.7% of cases, respectively. Pearson's chi-square test found no statistically significant association between p53 expression categories and Gleason grade group (χ²=10.253, p=0.248).

Association between Ki67 proliferation index and Gleason grade group

An analysis revealed a statistically significant association between the Ki67 proliferation index and Gleason grade group. The distribution showed a general trend of increasing proliferative activity with higher grade group. Specifically, low-grade group tumor (Grades 1 and 2) was predominantly associated with lower Ki67 indices (1+), with 80% of Grade group 2 tumors falling in the lowest category (<2%). In contrast, higher-grade group tumors (Grades 3, 4, and 5) were primarily characterized by an elevated Ki67 index (2-25%), accounting for 85.7%, 100%, and 66.7% of cases, respectively.