**Question:** All are true about Gleason's score except

A. Gleason's score is used to grade prostate cancer.
B. Gleason's score is a numerical score between 1 and 5.
C. Gleason's score is not influenced by the presence of necrosis or mitosis.
D. Gleason's score is a subjective scoring system based on histopathological examination.

**Core Concept:** Gleason's score is a grading system used in prostate cancer diagnosis. It is named after the pathologist Dr. Gleason who developed it in 1966. Gleason's score is a numerical grade based on the histopathological examination of prostate biopsy specimens.

**Why the Correct Answer is Right:** Gleason's score is rightly considered a numerical score between 1 and 5 because it quantitatively grades prostate cancer based on the pattern and grade of tumor cells in biopsy samples. Each biopsy slide is assessed for two primary patterns, which are assigned scores of 1-5. The two scores are then combined to generate a single Gleason score.

**Why Each Wrong Option is Incorrect:**

A. Gleason's score is not used to grade prostate cancer. In reality, Gleason's score is a crucial tool for grading prostate cancer, providing important information about the aggressiveness and prognosis of the disease.

B. Gleason's score is a subjective scoring system, as it relies on human pathologists' assessment of biopsy samples. Although there are guidelines to ensure consistency in scoring, it is still subjective to some extent.

C. Gleason's score takes into account the presence of necrosis and mitosis, both of which indicate cancer severity. Therefore, this statement is incorrect.

D. Gleason's score is a quantitative system, but the scoring is based on the interpretation of biopsy samples by pathologists. It is not a purely quantitative method.

**Correct Answer Explanation:**

The correct answer, D, highlights the fact that Gleason's score is a subjective scoring system based on histopathological examination of prostate biopsy samples. It is a useful tool for predicting the prognosis and treatment response of prostate cancer.

**Why Each Wrong Option is Incorrect:**

A. This option is incorrect because Gleason's score is used to grade prostate cancer and provide information about its aggressiveness and prognosis.

B. Although Gleason's score relies on human pathologists' assessment, it is a more refined system compared to older grading systems and is designed to provide a more accurate representation of cancer aggressiveness.

C. This statement is incorrect because necrosis and mitosis are considered when assessing the severity of prostate cancer and are taken into account in Gleason's score.

D. This option is incorrect because Gleason's score is a subjective system based on histopathological examination, but it is used to predict the prognosis and treatment response of prostate cancer.

**Clinical Pearls:**

1. **Gleason's score** is a crucial tool for predicting the prognosis and treatment response of prostate cancer. It reflects the pattern