• No results found

The limitations that were encountered in the course were due to patients defaulting during follow up or due death from other co-morbidities resulted in them being excluded from the study.

During the course of the study, patients may also travel or relocate which will make it difficult or impossible to collect data during follow up even when contacted via phone calls. These factors also made it difficult to follow up patients for periods longer than the duration of the study.

40 CHAPTER FIVE

RESULTS

A total of sixty-two patient were initially recruited for the study but data from sixty-one patients were analyzed after one patient died 14 days post orchiectomy. Thirty (49.18%) patients had bilateral total orchiectomy (BTO) while thirty-one (50.82%) patients had bilateral subcapsular orchiectomy (BSO). Overall mean age was 69.5 ± 7.5 years (range= 52-85 years). Mean age in BTO group was 69.7 ± 5.7 years while that of BSO group was 69.3 ± 9.0 years.

Forty-eight patients (78.7%) presented with lower urinary symptoms. Other modes of presentation include- low back pain in 22 patients (36.1%), significantly weight loss in 10

41 (16.4%), and lower limb weakness in 13 (21.3%) of which 7 (11.5%) had

paraplegia/paraparaesis on examination. Three (3) of the 7 patients with paraplegia were in the BSO group while four (4) were in the BTO group. Forty-six patients (75.4%) had features suggestive of prostate malignancy on digital rectal examination.

All patients were diagnosed as adenocarcinoma of the prostate histologically. The distribution of primary Gleason grades and Gleason scores between the 2 different groups is as shown in tables 1 and 2.

Table 1- Distribution of Gleason grades amongst studied patients Primary Gleason

grades

BSO group BTO group Total (% of all patients)

2 1 5 6 (9.8%)

3 8 10 18 (29.5%)

4 14 13 27 (44.3%)

5 8 2 10 (16.4%)

Total 31 30 61 (100%)

The most frequent primary Gleason grade was 4 (44.3%) as shown in table 1 while the most frequent Gleason score was 9 (24.6%) as shown in table 2. The BSO group had 8 (80%) of the patients with Primary Gleason grade 5 while the BTO group had 2 (20%). Cumulatively, 68.9%

had Gleason scores of 7, 8 or 9 (Table 2).

Table 2- Gleason scores of the patients studied Gleason scores Number of

patients in BSO group

Number of patients in BTO group

Total (% of all patients)

4 1 2 3 (4.9%)

5 2 2 4 (6.6%)

6 4 6 10 (16.4%)

7 7 7 14 (23.0%)

42

8 7 6 13 (21.3%)

9 8 7 15 (24.6%)

10 2 0 2 (3.3%)

Total 31 30 61 (100%)

Overall, the mean combined testicular volume was 47.45cm3 ± 16.93 cm3. The mean combined testicular volume was 44.7 ± 15.7 cm3 in the BTO group while that of the BSO group was 50.3 ± 17.9 cm3 (p-value= 0.20). Pre-orchiectomy serum PSA was elevated in all patients recruited for this study with an average serum PSA of 49.35ng/ml (minimum= 8.12ng/ml and maximum=

88.36ng/ml). On analysis of the individual groups of patients, the average pre-orchiectomy serum PSA levels were 52.04ng/ml and 46.58ng/ml in the BSO and BTO groups respectively as shown in Table 3 (p-value = 0.31). Average pre-orchiectomy testosterone levels were

25.23nmol/L and 21.48nmol/L in BTO and BSO groups respectively as also shown in Table 3 (p-value= 0.35). There was also no statistically significant difference in pre-orchiectomy serum testosterone levels on comparison of the 2 groups (Table 3).

Table 3- Comparison of average values of serum testosterone and PSA (with their standard deviations) at the different time intervals

Serum testosterone (nMol/L) Serum PSA (ng/ml) Study

group

N

Pre-orchiectomy

At one month

At three months

Pre-orchiectomy

At one month

At three months

Fractional fall in PSA at 3 months BSO

group

31 25.23 ± 14.74

2.98 ± 2.24

1.98 ± 2.56

52.04 ± 21.77

14.78

± 18.87

11.30 ± 22.56

0.24 ± 0.53

BTO group

30 21.48 ± 16.65

0.82 ± 0.47

0.63 ± 0.20

46.58 ± 19.95

11.69

± 6.38

5.15 ± 4.73

0.16 ± 0.26

P-value 0.356 0.000 0.007 0.311 0.394 0.147 0.406

43 Overall 61 23.39 ±

15.69

1.92 ± 1.95

1.31

±1.94

49.35 ± 20.91

13.25

± 14.45

8.28 ± 16.58

0.20 ± 0.42

The serum testosterone levels at one month and three months post orchiectomy in the BSO group were 2.98 ± 2.24 nMol/L and 1.98 ± 2.56 nMol/L respectively while that of the BTO group were 0.82 ± 0.47 nMol/L and 0.63 ± 0.20 nMol/L respectively as shown in Table 3 (p-value= 0.00 and 0.007 respectively at one and three months).

Serum testosterone levels of all patients in the BTO group were less than 1.735 nmol/L

(represents the castrate level of serum testosterone) at one month post-orchiectomy as shown in Figure 1 while serum testosterone of 10 patients (32.25%) in the BSO group were below this level as shown in Figure 2 at this same time.

At three months post orchiectomy as shown in Figure 2, the number of BSO group patients with serum testosterone level below 1.735 nmol/L had increased to 19 (61.29%). The serum

0 10 20 30 40 50 60 70 80 90 100

1 3 5 7 9 11 13 15 17 19 21 23 25 27 29

Serum testosterone levels in nmol/L

Serial numbers of patients in BTO group

Figure 1- Pattern of serum testosterone in BTO group

Pre-orchiectomy At 1 month At 3 months

44 testosterone level of one patient in the BSO group rose from 7.89nmol/L at 1 month post

orchiectomy to 15.06nmol/L at 3 months. Apart from this patient, the maximum serum testosterone level in the BSO group at 3 months post orchiectomy was 4.13nmol/L.

As also shown on Table 3, the average serum PSA values at one month and three months post orchiectomy in the BSO group were 14.78 ± 18.87 ng/ml and 11.30 ± 22.56 ng/ml respectively while that of BTO group at these same times were 11.69 ± 6.38 ng/ml and 5.15 ± 4.73 ng/ml respectively (p-values at one month and three months were 0.394 and 0.147 respectively).

Serum PSA levels at three months post-orchiectomy were calculated as fractions of the pre-orchiectomy serum PSA levels for the different groups of patients as shown in Table 3. The value was 0.24 ± 0.53 in the BSO group while the value in the BTO group was 0.16 ± 0.26 (P value=0.406).

0 10 20 30 40 50 60 70

1 3 5 7 9 11 13 15 17 19 21 23 25 27 29 31

Serum testosterone level in nmol/L

Serial numbers of patients in BSO group

Figure 2- Pattern of serum testosterone in BSO group

pre-orchiectomy At 1 month At 3 months

45 Figures 3 and 4 show the serum PSA levels in the BTO and BSO groups respectively at one and three months post orchiectomy. Five (5) patients (8.2% of all patients) recorded increases in serum PSA levels at three months post-orchiectomy from the values at one month.

One of such rises in PSA occurred in the BTO group while the other four occurred in the BSO group. Only one PSA rise in the BSO group coincided with a rise in serum testosterone at three months.

0 10 20 30 40 50 60 70 80 90

1 3 5 7 9 11 13 15 17 19 21 23 25 27 29

Serum PSA values in ng/ml

Serial numbers of patients in BTO group

Figure 3- Pattern of serum PSA values in BTO group

Pre-orchiectomy At 1 month At 3 months

46 Analysis of the quality of life scores

The total FACT-G scores that assessed the general quality of life and FACT-P scores that factored in additional concerns as regards patients with prostate cancer were calculated. Results are as shown in Table 4 below.

Table 4- Average FACT-G and FACT-P scores of the studied respondents Pre-orchiectomy

quality of life

Quality of life one month post orchiectomy

Quality of life three months post orchiectomy Study

group

N FACT-G FACT-P FACT-G FACT-P FACT-G FACT-P

BSO group

31 76.63 ± 15.31

101.95 ± 22.75

79.12 ± 17.10

106.31 ± 21.09

78.45 ± 15.54

107.15 ± 19.44 BTO

group

30 79.84 ± 16.08

105.36 ± 22.98

81.83 ± 13.87

109.82 ± 19.52

81.76 ± 15.76

109.88 ± 21.99

P-value 0.429 0.563 0.499 0.533 0.411 0.609

Overall 61 78.20 ± 15.64

103.62 ± 22.74

80.45 ± 15.52

108.04 ± 20.24

80.08 ± 15.61

108.49 ± 20.60

0 20 40 60 80 100 120

1 3 5 7 9 11 13 15 17 19 21 23 25 27 29 31

Serum PSA values in ng/ml

Serial numbers of patients in BSO group

Figure 4- Pattern of PSA values in BSO group

Pre-orchiectomy At 1 month At 3 months

47 As shown in Table 4, the FACT-P scores at one month in the BSO and BTO groups were 106.31

± 21.09 and 109.82 ± 19.52 respectively (p-value= 0.533) while at three months, the scores were 107.15 ± 19.44 and 109.88 ± 21.99 in the BSO and BTO groups respectively (p-value= 0.609).

Table 5 shows the subscale scores at three months post orchiectomy of which the Physical wellbeing score (PWB score) in the BSO group was 19.97 ± 5.36 while that of the BTO group was 22.57 ± 4.32.

Table 5- Subscale scores at three months post orchiectomy

Study groups PWB score SWB score EWB score FWB score PCS score BSO group 19.97 ± 5.36 21.03 ± 4.31 18.80 ± 4.65 18.65 ± 6.97 28.70 ± 7.06 BTO group 22.57 ± 4.32 21.33 ± 4.60 19.20 ± 3.89 18.67 ± 7.09 28.12 ± 7.49

p-value 0.041 0.793 0.721 0.991 0.754

Item P5 (I am able to feel like a man) on the FACT-P questionnaire was analyzed separately.

This item was used to assess the body image and self-perception of the patient post orchiectomy.

In response to item P5 on the questionnaire pre-orchiectomy, 37.70% of the respondents irrespective of the groups chose the ‘quite a bit option and this was reflected in the individual groups as demonstrated in figures 5 and 6.

48 By 1 month and increasingly so in 3 months, the ‘a little bit’ option was the most frequent

response in both groups (Figures 5 and 6).

0 2 4 6 8 10 12 14 16

Pre-orchiectomy At 1 month At 3 months

Number of respondents

Time intervals

Figure 5- Responses to item P5 (I am able to feel like a man) in BSO group

Not at all A little bit Somewhat quite a bit Very much unanswered

0 2 4 6 8 10 12 14 16

Pre-orchiectomy At 1 month At 3 months

Number of respondents

Time intervals

Figure 6- Responses to item P5 (I am able to feel like a man) in BTO group

Not at all A little bit Somewhat Quite a bit Very much Unanswered

49 As shown in Table 6, average item P5 scores at 1 month were 190 ± 1.33 in BSO group while it was 1.87 ± 1.17 in the BTO group (p-value= 0.909). At 3 months as also shown in Table 6, average item P5 scores were 1.20 ± 1.13 in BSO group while it was 1.38 ± 1.08 in the BTO group (p-value= 0.536).

Table 6- Comparison of mean P5 item scores at different time intervals

Groups Mean P-value

Pre-orchiectomy P5 scores

BSO 2.33 ± 1.30 0.558

BTO 2.52 ± 1.30

P5 scores at 1 month BSO 1.90 ± 1.33 0.909

BTO 1.87 ±1.17

P5 scores at 3 months

BSO 1.20 ± 1.13 0.536

BTO 1.38 ± 1.08

CHAPTER SIX DISCUSSION

Cancer of the prostate is a major cause of morbidity and mortality in Nigerian men. 5 Androgen deprivation therapy, whether surgical or medical, is usually the initial therapy for locally advanced or metastatic disease. It constitutes the bulk of therapy for most prostate cancer patients in Nigeria since most present late with advanced disease. 3, 5

All patients in this study had androgen deprivation therapy in the form of bilateral orchiectomy for histologically diagnosed, advanced prostate cancer after clinical assessment. Overall mean age was 69.5 ± 7.5 years (range= 52-85 years) which is in keeping with previous reports from Nigeria that prostate cancer was commonest in men in their 7th decade (age 60-69 years). 3 There were statistically significant differences in mean serum testosterone values at one month and three months post orchiectomy. On average, patients who had bilateral subcapsular

50 orchiectomy had higher serum testosterone levels at these times when compared to those that had bilateral total orchiectomy. This finding conflicts with findings from previous studies by Tacker et al, 16 Chapman et al, 17 and Zhang et al 15 which found no significant differences in serum testosterone levels on comparison between BSO and BTO. One of the first prospective studies that compared serum testosterone post BSO to that post BTO was by Tacker et al 16 and it was conducted using rats and not humans as in this study. Subsequent studies by Chapman et al 17 and Zhang et al 15 were prospective studies conducted on humans. However, Zhang et al 15 did not state the timing of the post orchiectomy serum testosterone assay which was only done once and the patients were subsequently followed up with serum PSA for 3 yrs.

In this study, post orchiectomy serum testosterone levels in the BSO group also showed wide variability in values as shown by the standard deviation from the mean especially when compared to that of the BTO group and by one month post orchiectomy, only 10 (32.25%) of them had achieved castrate levels of testosterone. However by three months, about two third (61.29%) of the patients in the BSO group had achieved castrate levels of serum testosterone though one patient in the BSO group had a significant rise of serum testosterone at three months.

The Leydig cells in the tunica albuginea and epididymis left behind after BSO may be

contributing to this non-uniform decline in serum testosterone but a previous study by Burge 43 had demonstrated that attempts at further stimulation by administration of human chorionic gonadotropin (HCG) did not reveal any differences in serum hormone levels in both BSO and BTO patients. The results from his study suggested that the Leydig cells in these locations were not hormonally active.

Bilateral subcapsular orchiectomy relies on the complete removal of all intra-testicular tissue and is more dependent on technique than bilateral total orchiectomy. 13 Though the principles of

51 performing a subcapsular orchiectomy were strictly adhered to by the researcher in this study, the variability in serum testosterone levels in the BSO group may possibly be accounted for by testicular parenchyma inadvertently left behind during the procedure. Errors in technique that result in significant remnant testicular parenchymal tissue being left behind may contribute to the slow decline and less frequently, rise in serum testosterone noticed in few patients in the BSO group. In contrast, only one patient in the BTO group had not achieved castrate serum

testosterone levels at one month.

The possibility of re-growth of testicular parenchyma as an explanation for such rise in serum testosterone seems remote since human Leydig cells seemed to have no capacity for

regeneration, or endocrine function, despite the fact that some of these cells are present

morphologically in the tunica albuginea or spermatic cord. This fact was demonstrated in studies by Burge 43 and Senge et al 45 (conducted on humans and rats). In the study by Senge et al 45, no rise of testosterone concentrations could be observed in patients up to 8 months after subcapsular orchiectomy when compared to the testosterone concentrations that increased parallel to

regeneration of Leydig cells (while LH concentrations declined) in rats in which testicular necrosis had been produced by cadmium chloride.

Post-orchiectomy serum PSA levels on the other hand decline equally and there were no statistically significant differences on comparison between the 2 groups of patients. This is similar to findings reported by Zhang et al 15 in which tumour response in the two groups when assessed by prostate-specific antigen were similar. Zhang et al 15 followed up their patients till 3 years post orchiectomy. These results suggest that both BSO and BTO lead to similar responses and outcomes in advanced prostate cancer.

52 However, 5 patients (8.2% of all patients) recorded increases in serum PSA levels at three

months post-orchiectomy when compared to the values at one month. Only in one patient did a rise in serum PSA value (from 1.32ng/ml at one month to 4.93ng/ml at three months) correspond with a rise in serum testosterone value that never neared the castrate range (from 7.89nmol/L at one month to 15.06nmol/L at three months). The rest probably were evidence of onset of biochemical castration resistance.

Quality of life of prostate cancer patients

The total FACT-G and FACT-P scores at one month and three months were not significantly affected by the type of orchiectomy offered.

The physical wellbeing score (PWB score) at 3 months post orchiectomy was the only subscale score that was significantly lower (indicating lower quality of life as regards this subscale) in the BSO group compared to the BTO group. Whether the presence or absence of a palpable ‘testis’

in the scrotum affected the PWB score directly could not be deduced. Age distributions in the 2 groups were similar with no statistical difference. Out of the 7 patients with paraplegia, 3 were in the BSO group but it was noticed during analysis that 8 out of 10 of the patients with primary Gleason grade 5 were in the BSO group and that 5 out of the 6 patients with primary Gleason grade 2 were in the BTO group. Whether this skewed primary Gleason grade distribution affected the clinical outcome instead of the type of procedure could not be ascertained in this study and may require further study to investigate its effect.

Item P5 (I am able to feel like a man) on the FACT-P questionnaire which was used to assess the body image and self-perception of the patient post orchiectomy was analyzed separately. Frequency of responses and mean item scores were compared. Assessment of the

53 responses and scores for the item P5 revealed almost equal declines in scores for this item but no significant differences were detected when both groups were compared. In response to item P5 on the questionnaire pre-orchiectomy, most respondents irrespective of the groups chose the

‘quite a bit option (37.70%) and this was reflected in the individual groups as demonstrated in figures 5 and 6. By 1 month and increasingly so in 3 months, the ‘a little bit’ option was the most frequent response in both groups (Figures 5 and 6). These finding supports the fact that androgen deprivation therapy negatively affected patient’s perception of self as a man. Lucas et al 72

studied 15 patients with stage D prostate cancer before and after surgery and reported that the overall quality of life and sex-role identity were not affected by orchiectomy which conflicts with findings in this study that demonstrated a decline in self-perception as a man as assessed by item P5. In this study, the patients’ self-perception as men was affected by the surgical androgen deprivation therapy, irrespective of the type of orchiectomy done. Some factors may be

responsible for this. All the patients had already been counselled prior to orchiectomy about the expected complications like loss of libido and penile erectile ability. Most of them may have already resigned themselves to the fact that the palliative treatment being offered (which was what they could probably afford) implied losing their testes and its attendant complications.

54 CHAPTER SEVEN

CONCLUSION AND RECOMMENDATIONS

Androgen deprivation therapy forms the bulk of therapy for advanced prostate cancer. Bilateral subcapsular orchiectomy has been said to have some psychological benefit due to the presence of palpable remnants in the scrotum. However doubts have persisted about its efficacy in lowering testosterone levels.

In this study, serum testosterone levels on average were significantly higher in the BSO group at one month and three months when compared to levels in the BTO group. Serum testosterone levels of patients in the BSO group were also more variable.

Serum PSA levels declined over three months post orchiectomy without any difference on comparison of the groups implying that there is no difference between BTO and BSO as treatment modalities.

55 Quality of life scores (FACT-P and FACT-G) and item scores relevant to perception of self as a man also did not differ. Firstly, this implies that both types of orchiectomies lead to similar biochemical and clinical outcomes/results. Secondly, performing a bilateral subcapsular orchiectomy did not lead to any significant difference in psychological benefit as regards perception of masculinity when compared to performing a bilateral total orchiectomy.

The following recommendations are made

1. Bilateral subcapsular orchiectomy is an effective option for surgical androgen ablation and should be offered to patients as far as principles and techniques of the procedure are strictly adhered to.

2. Urologists in sub-Saharan Africa should have no reservations about offering both procedures because there was no clear psychological benefit accruing to any of the procedures in our study population.

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