“The importance of Atypical Small Acinar Proliferation”
Objective: To investigate the prostatic adenocarcinoma (PA) detection rate in follow up biopsises with an initial diagnosis of atypical small acinar proliferation (ASAP).
Materials and Methods: In this study, the cases of ASAP diagnosis in prostate needle biopsy materials between January 2010 and December 2016 were retrospectively analyzed and the correlation between the results and the follow-up diagnoses of ASAP-diagnosed cases was investigated.
Results: 62 cases with ASAP were included in the study and 21 (34%) of them were detected as PA after the follow-up diagnoses. Also ASAP and PA were detected at different localizations in 38% of the cases.
Conclusion: We are on the opinion that it is important to increase the number of samples taken from other localizations as well as ASAP diagnosed quadrants when taking follow-up biopsies.
Keywords: Atypical Small Acinar Proliferation; Prostate Cancer; Prostate Needle Biopsy
Prostate cancer is the most common type of cancer in men after lung cancer. For males, cancer takes the fifth place among the causes of deaths. Globally 1.1 million men were diagnosed with prostate cancer in 2012 and this reportedly increased in frequency. For this reason, information about this disease is increasingly significant (1). In order to avoid prostate cancer, it is necessary to check the prostate in a timely manner and maintain it with Cialis. In Canada and the United States you can buy Cialis in any pharmacy prescription.
Some of the prostate biopsies can not be clearly distinguished from benign and malign, and in these cases atypical small acinar proliferation, which is suspicious for adenocarcinoma but lacks sufficient diagnostic value, is called ASAP (2). ASAP as a term was first used by Bostwick et al. in 1993 in the cases of unclear malign-benign distinction from the cytologic and architectural side (3,4). On condition that atypical glandular structure has insufficient infiltrative growth, it exists in a small focus, it is seen in a very little gland, it has less than 10% of the number of cells with nucleoli specificity, and it has insufficient nuclear expansion and hyperchromacy, ASAP is preferred instead of prostatic adenocarcinoma in, (3, 4, 5). Approximately 2-5% of biopsies are reported as ASAP, and the rate of detection of prostatic adenocarcinoma (PA) in recurrent biopsies of ASAP-diagnosed cases ranges from 21% to 51% (6, 7, 8). Because of this high risk, these patients are re-biopsied within 3 to 6 months (6).
Fine-needle biopsy performed with the presence of transrectal ultrasound (TRUS) under the follow-up of ASAP and in PA is the most preferred and reliable method. In this study, we also investigated the rate of PA recurrence and the relationship between ASAP and PA localizations in recurrent biopsies of ASAP-diagnosed patients.
Material and Method
The cases with ASAP diagnosed in 12 dial prostate needle biopsy materials between January 2010 and December 2016 in our institution were retrospectively reviewed. In 6 years, 75 patients were diagnosed with ASAP (figure 1 a-b) and 62 of these (82%) were re-biopsied. The follow-up data of 13 patients couldn’t be reached. Sixty-two cases with follow-up biopsies were included in this study. Follow-up diagnoses (benign, PA) were noted. PA diagnosed quadrants (figure 2 a-b) of the cases with PA diagnosis after the follow-up were compared with the ASAP diagnosed quadrants. In addition, the prostate-specific antigen (PSA) levels of the patients, prostate volumes (taken by ultrasonography as the upper limit of 20 ml) and patient ages were recorded and classified with the follow-up diagnosis.
The study was approved by our local ethics committee (37732058-514.10).
The D’Agostino-Pearson test was used to determine whether the data is consistent with the normal distribution. The variables with normal distribution between the two groups were analyzed by independent t test, and those without normal distribution were analyzed using Mann-Whitney test. The correlation between continuous variables was analyzed using Pearson correlation. P value was calculated as double-edged, and p values less than 0.05 were considered significant. Statistical analysis was performed with the Medcalc program (Medcalc, ver 12, Ostend, Belgium).
The mean age of patients diagnosed with ASAP was 66, the mean age of patients diagnosed with cancer was 67, and the mean age of the patients reported as benign was 65. There was no significant age relationship between patients with PA and those without PA (p: 0.642). PSA values of the patients ranged from 2.1 to 19.8 ng / mL and median PSA value was 6.2 ng / ml. The PSA level of 13 patients was below 4 ng / ml, and 4 (19%) of them were found to have PA. In other words, 4 of the 21 patients whose PA was detected had a PSA level below 4 ng / ml. When the PSA values were compared, it was observed that there was no significant relationship between PA seen and not seen after follow-up (p: 0.296). Patients were divided into two groups with prostate volumes less than or more than 20 ml. There was no significant relationship between prostate volumes and follow-up diagnoses (p: 0.648).
It was seen that 21 (34%) patients were diagnosed with PA and 41 (66%) were diagnosed as benign after the follow up of the patients. In 5 (24%) of the cases, the cancer was in right and left lobes while ASAP was localized in the left lobe, in 4 (19%) of the cases, the cancer was right and left lobes while ASAP was localized in right lobe, in 4 (19%) of the cases, the cancer was again in the right lobe while ASAP was localized in the right lobe, in 4 (19%) of the cases, the cancer was in the left lobe while ASAP was localized in the right lobe, in 2 (9,5%) of the patients, the cancer was in the left lobe while ASAP was localized in the right and left lobes, in 2(9,5%) of the patients, both the cancer and ASAP were in the same lobe (right + left lobe) (Table 1).
As prostate cancer is one of the common cancers and deaths due to prostate cancer are located in the upper ranks among cancer-caused deaths, the significance of early diagnosis studies is increasing. Prostate needle biopsies are the most commonly used method for diagnosing prostate cancer and the most useful method for diagnosis. Approximately 2-5% of the prostate biopsies cannot clearly distinguish between benign and malign, and in these cases they are termed as ASAP, atypical small acinar proliferation which has inadequate diagnostic features.
ASAP was originally used by Bostwick et al. in 1993, but Iczkowski and colleagues conducted the first study using statistical data in 1997. In the first study by Iczkowski and colleagues with 33 cases, 15 (45%) cases were found PA after the followed up. Then, in a broader study they conducted with 295 cases, 125 (42%) cases after the follow-up were found to have PA. In the study of Ericson and colleagues in 2017, 15 (31%) of 49 cases were found PA (2,9,10). In the present study, 75 patients were diagnosed with ASAP within 6 years, 62 of them underwent follow-up biopsy and 21 (34%) of 62 patients were found to have PA. The result of this study was found to be consistent with the literature. This once again reminds us of the importance of the follow-up of ASAP patients.
Studies have reported that 14% of patients with prostate cancer have PSA below 3 ng / ml, 23-24% at 3-4 ng / ml, and 62% over 4 ng / ml. According to this, PSA levels in 38% of patients with prostate cancer are lower than 4 ng / ml (11,12,13). In our study, when PSA values of patients were examined, it was seen that PSA levels in 4 (19%) of 21 patients were lower than 4 ng / ml in PA patients. Cancer could have been missed in 19% of patients if ASAP-diagnosed cases had been followed up with PSA values instead of being followed by prostate needle biopsy. Furthermore, when the prostate volumes of patients were examined, it was seen that there was no significant relation between prostate volume and the diagnoses after follow-up. This suggests that follow-up of prostate volume in patients with ASAP diagnosis is not a definitive method for distinguishing benign and malign.
It is unclear what the most useful follow-up biopsy approach is in ASAP diagnosed cases. In the literature, the rate of cancer seen on the same side of the ASAP site and the follow-up biopsy was reported as 65%, and this rate was found to increase to 88% with the near region biopsy (14). It was reported that the rate of getting cancer increased with taking biopsy from the parts except ASAP localization (14,15,16). In a study consisting of large patient groups, 56% of the cancer cases with ASAP were reported to be ipsilateral and 27% of them were contralateral. In 39% of the cases, cancer was detected in the areas outside the place where ASAP was detected in the first biopsy. Therefore, if the needle biopsy had been performed only in the ASAP place, cancer could have been missed in the 39% of the patients (2). In our study, ASAP were located in the right lobe while cancer was found in the left lobe in 4 (19%) cases. If the follow-up biopsy had been performed on only ASAP-detected lobotomy, 19% of the patients could not have had cancer. In addition, 4 patients with cancer and ASAP had the same lobe but in different localization. If the follow-up biopsy had been performed only in the same localization, cancer could not have been detected in 38% of the patients (8 patients). This demonstrates once again the necessity of prostate needle biopsy in numerous and different localizations in follow-up biopsies of cases detected in ASAP in first biopsies – Read more at Part-2.
|By Dr. Ravi Mootha, M.D.||On: May 07, 2019 at 19:21:15|