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ORIGINAL ARTICLE
Year : 2022  |  Volume : 21  |  Issue : 2  |  Page : 153-157  

Prostate cancer characteristics: A descriptive analysis of clinical features at presentation in the last decade in a black African community


1 Faculty of Medical Sciences, College of Medicine, University of Nigeria Enugu Campus, Enugu, Nigeria
2 Department of Surgery, Urology Unit, University of Nigeria Teaching Hospital, Enugu, Nigeria

Date of Submission24-Oct-2020
Date of Acceptance02-May-2021
Date of Web Publication6-Jul-2022

Correspondence Address:
Ikenna I Nnabugwu
Department of Surgery, Faculty of Medical Sciences, College of Medicine, University of Nigeria, Enugu Campus, PMB 01129 Enugu
Nigeria
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Source of Support: None, Conflict of Interest: None


DOI: 10.4103/aam.aam_101_20

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   Abstract 


Background: Prostate cancer, previously reported as relatively rare in Nigeria, is currently the leading cancer and leading cause of cancer-related death in men. Late presentation appears to persist despite higher incidence rates and instituted awareness programs. This study assesses current prostate cancer indices at presentation to a 3rd tier referral hospital in South-east Nigeria and compares these indices with reported indices from previous decades. Materials and Methods: Retrospectively, the medical records of men presenting with histologically confirmed prostate cancer from January 2009 to April 2018 were reviewed. Age, spectrum and duration of clinical features, serum total prostate-specific antigen (tPSA), and prostate biopsy specimen Gleason Score (GS) at presentation were retrieved for the analysis using the SPSS software version 21. Obtained mean values and proportions were compared to reports from previous decades for observable shifts. Results: The medical records of 331 men 51–90 years of age (mean: 69.8 ± 8.0 years) were retrieved. Six (1.8%) men (median tPSA = 28.0 ng/ml; range 10.0–121.4 ng/ml) had screening-detected prostate cancer. About 72.0%, 52.0%, and 30.3% of men present with symptoms after 3 months, 6 months, and 12 months, respectively, and about 55.1% had other clinical features of disease progression beyond lower urinary tract symptoms. Symptom duration, serum tPSA (median 31.4 ng/ml; range 4.0–710.0 ng/ml), and % fPSA (median 20.6%; range 57.1%–8.6%) at presentation, as well as prevalent poorly-differentiated tumor (GS ≥7 [4 + 3] 62.2%) are yet to shift from reports from previous decades. Conclusions: Prostate cancer indices at presentation in South-eastern Nigeria, a resource-poor community in sub-Saharan Africa are yet to positively shift despite efforts at prostate cancer awareness.

   Abstract in French 

Résumé
Contexte: Le cancer de la prostate, déjà signalé comme relativement rare au Nigeria, est actuellement le principal cancer et la principale cause de décès par cancer chez les hommes. La présentation tardive semble persister malgré des taux d'incidence plus élevés et des programmes de sensibilisation ont été mis en place. Cette étude évalue les indices actuels du cancer de la prostate à la présentation à un hôpital de référence de troisième niveau dans le sud-est du Nigeria, et compare ces indices avec les indices rapportés des décennies précédentes. Méthodes: Rétrospectivement, les dossiers médicaux des hommes présentant un cancer de la prostate confirmé par histologie de janvier 2009 à avril 2018 ont été examinés. L'âge, le spectre et la durée des caractéristiques cliniques, l'antigène prostatique total sérique spécifique (tPSA) et l'échantillon de biopsie de la prostate Gleason Score (GS) à la présentation ont été récupérés pour analyse à l'aide de la version 21 de SPSS. Les valeurs moyennes et les proportions obtenues ont été comparées aux rapports des décennies précédentes sur les changements observables. Résultats: Les dossiers médicaux de 331 hommes âgés de 51 à 90ans (moyenne : 69,8 8,0 ans) ont été récupérés. Six hommes (1,8 %) (tPSA médiane = 28,0ng/ml; plage de 10,0 à 121,4ng/ml) avaient un cancer de la prostate dépisté. Environ 72,0%, 52,0% et 30,3% des hommes présentent des symptômes après 3mois, 6mois et 12mois respectivement, et environ 55,1% présentent d'autres caractéristiques cliniques de la progression de la maladie au-delà des symptômes des voies urinaires inférieures (LUTS). La durée des symptômes, le tPSA sérique (médiane de 31,4 ng/ml; fourchette de 4,0 à 710 ng/ml) et le %fPSA (médiane de 20,6 %; fourchette de 57,1 à 8,6 %) à la présentation, ainsi que la tumeur mal différenciée prévalente (GS 7{4+3} 62,2 %) ne sont pas encore passés des rapports des décennies précédentes. Conclusions: Les indices du cancer de la prostate présentés dans le sud-est du Nigeria, une communauté noire africaine pauvre en ressources, n'ont pas encore changé de façon positive malgré les efforts de sensibilisation au cancer de la prostate.
Mots-clés: Présentation à l'hôpital; Nigéria; Cancer de la prostate; Changements temporels

Keywords: Hospital presentation, Nigeria, prostate cancer, temporal changes


How to cite this article:
Ugwumba FO, Nnabugwu II. Prostate cancer characteristics: A descriptive analysis of clinical features at presentation in the last decade in a black African community. Ann Afr Med 2022;21:153-7

How to cite this URL:
Ugwumba FO, Nnabugwu II. Prostate cancer characteristics: A descriptive analysis of clinical features at presentation in the last decade in a black African community. Ann Afr Med [serial online] 2022 [cited 2022 Aug 13];21:153-7. Available from: https://www.annalsafrmed.org/text.asp?2022/21/2/153/349962




   Introduction Top


The 2018 GLOBOCAN report on the global burden of cancer put prostate cancer as the second most common cancer in men worldwide.[1],[2],[3] This 2018 report and others earlier highlighted absence of reliable national and subnational population-based cancer registries in many low- and medium-income countries (LMIC) as major challenge toward the generation of regional and global cancer data.[2],[3] This challenge notwithstanding, robust estimates of cancer incidences are achieved for utilization globally, deploying recognized models and statistical methods. Hospital-based reports, however, are crucial in revealing other disease details such as observed clinical features at presentation, treatment protocols, and challenges encountered which are also vital in proper decision-making and which may be lacking in population-based cancer registries in LMIC.[4],[5]

Reportedly, prostate cancer is currently the most common cancer and the most common cause of cancer death in men in Nigeria.[4],[6],[7] Although reported as relatively rare in the past, possibly due to gross under-reporting and absence of screening, more recent reports tend to counter such earlier disposition.[8],[9],[10] Despite this shift in incidence status, presentation at late disease stages appears to have persisted with the attendant poor management outcomes and high treatment burden.[10],[11] There are indications that many cancer awareness and health-promotion programs have been put in place to change the poor prostate cancer health indices for the better.[12] Moreover, a good number of these programs report good output and improved prostate cancer health indices, especially in the short term.[7]

Hospital-based reports from South-east region and other regions of Nigeria in previous decades reveal frightening prostate cancer health indices when compared to other better developed communities.[9],[11],[13] A survey of specialist caregivers in Nigeria in 2010 also revealed that very small proportion of men eligible for prostate cancer screening did access such screening services.[14] In addition, surveys of populations of men revealed low levels of knowledge on prostate cancer necessitating repeated calls on key stakeholders to deploy strategies directed toward improving the lot of men as regards prostate cancer.[15],[16] In this past decade in South-east Nigeria, are these indices still grim? There are mixed reports of persistence of poor prostate cancer indices and some improvement in these indices from other regions of Nigeria and from other LMIC.[13],[17],[18] For instance, there is report in 2012 of reduction in proportion of prostate cancer patients presenting to a 3rd tier referral hospital in advanced disease stages in the preceding decade from the southern region of Nigeria.[8] On the other hand, a similar study from another developing country utilizing medical records documented about the same period reports no significant shift in observed prostate cancer indices.[18]

Therefore, the primary objective of this study is to determine in this last decade, the prostate cancer indices at presentation to a 3rd tier referral hospital in South-east Nigeria by conducting a retrospective review of medical records. Secondarily, this study will determine any temporal changes in these indices as compared to reported prostate cancer indices from previous decades.


   Materials and Methods Top


The medical records of men presenting with histologically confirmed cancer of the prostate from January 2009 to April 2018 to a 3rd tier medical care facility in South-east Nigeria were retrieved and reviewed retrospectively. The medical care facility situated in South-east Nigeria serves as a referral center for all the provinces within the region, has 3 urology units amidst other surgical and nonsurgical units and a radio-oncology unit.

The variables of interest from the medical records were the age of these men at presentation, symptom-driven diagnosis or screening-detected diagnosis, the duration of symptoms before presentation, the spectrum of symptoms at presentation, and the values of the serum total prostate-specific antigen (tPSA) at presentation. Other variables of interest are the documented clinical stage of the disease and the core-needle biopsy Gleason score (GS).

The Statistics Package for the Social Sciences (IBM SPSS Co., Armonk, NY, USA) software version 21 was used for all analyses. The University of Nigeria Teaching Hospital Bioethics committee approved of this study.


   Results Top


In all, 331 medical records are retrieved for this review. They are all black men from 51 years to 90 years of age (mean: 69.8 ± 8.0 years), and 97% of the men are of Igbo ethnic extraction. Level of formal education attained is specified for 293 men: 169 (57.7%) of these men acquired more than primary level of formal education.

Only 6 (1.8%) men were evaluated as a result of elevated serum tPSA in the absence of any symptoms referable to prostate cancer. These men are from 68 years to 72 years of age (mean 69.8 ± 1.8 years), 4 acquired formal education beyond primary level, 1 had only primary level formal education while the formal education status of 1 is not stated. The serum tPSA values of these men at presentation are from 10.0 ng/ml to 121.4 ng/ml (median 28.0 ng/ml; IQR 16.8-52.9). In 2 of these 6 men, the digital rectal examination (DRE) findings are summarized as suspicious for malignancy while in 5 men, the transabdominal ultrasonography impressions were reported as suspicious of malignancy. The report of pelvic computed tomography (CT) scan in 1 of 4 men who could access the investigation is organ-confined while prostate biopsy GS in each of these 6 men is 6 (3 + 3).

In 325 medical reports, the men presented with symptoms. [Table 1] is a description of the clinical features of these men at presentation.
Table 1: Background and clinical features of men presenting with symptoms leading to histological diagnosis of prostate cancer

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In 246 (75.7%) and 266 (81.8%) of men presenting with symptoms, respectively, DRE findings and transabdominal ultrasonography features are summarized as suspicious of malignancy of the prostate. Pelvic CT scan in 9 men report prostate with suspicious features. Serum tPSA, documented in 207 men presenting with symptoms, has a median value of 31.4 ng/ml (range 4.0–710.0 ng/ml; IQR 14.9–55.0). Similarly, the median percentage-free PSA (%fPSA) is 20.6% (range 57.1–8.6; IQR 29.1-14.5). In 202 (62.2%) of these men, the GS from prostate biopsy is ≥7 (4 + 3). Spinal magnetic resonance imaging could be done for 8 of the men presenting with paraparesis/paraplegia defining the nature of the lesion on the spine.

In [Figure 1], [Figure 2], [Figure 3], variations in the duration of symptoms at presentation, in serum tPSA at presentation and in prostate biopsy GS over the years covered by the review are shown as line graphs.
Figure 1: The average duration of symptoms at presentation to specialist care at the 3rd tier hospital in each year. There is no evidence that men are presenting earlier with shorter symptom duration at first presentation

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Figure 2: Changes in the average total prostate-specific antigen values among men presenting with symptoms leading to histologic diagnosis of prostate cancer from 2009 to 2018. There is no observable reduction in median serum total prostate-specific antigen at presentation

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Figure 3: Variation in mean Gleason score of men presenting with histologic diagnosis of prostate cancer from 2009 to 2018. There is no evidence of shift in mean Gleason score at presentation toward less aggressive tumors

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   Discussion Top


The later part of the 20th century and moving into the 21st witnessed increasing call for mobilization of individuals for better awareness of cancers especially within the LMIC.[12],[19] Organizations and governments continue to commit resources to this end with the target that increasing number of persons will acquire capacity to make decisions that will impact positively on earlier cancer detection and curative treatment intents.[12] Expectedly, increasing proportions of cancer cases are to be diagnosed in early stages through increasing utilization of cancer screening recommendations and through earlier recognition of symptoms that require prompt further evaluation which will bring about early presentation to appropriate medical care facility for prompt diagnosis.[19] Unfortunately, the absence of robust population-or subpopulation-based cancer registries in many LMIC poses a challenge to recognition of changing cancer indices at presentation. Periodic hospital-based audits and retrospective reviews of cases thence become insightful, the shortfalls of these notwithstanding

The ages of men from this review suggest that over the decades, there has not been any change in the average age of men presenting with prostate cancer.[10] Of all the men reviewed in this study, only 1.8% had screen-detected prostate cancer. Many studies on willingness to undertake prostate cancer screening by men in the regions of Nigeria return good proportion of respondents as willing to access screening services.[20],[21] It appears this willingness is not put in practice after all,[20] in contrast to what is obtainable in better developed countries.[22] Therefore, other access barriers to cancer screening beyond willingness, such as financial and topographical access barriers to cancer screening, need to be addressed.[23]

In the majority of men in this study and in other studies from LMIC, the diagnosis of prostate cancer is based on some symptoms attributable to prostate enlargement, to local tissue invasion, or to distant metastasis [Table 1]. More than 95% of men presenting with symptoms have lower urinary tract symptoms (LUTS), and a little above half (55.1%) of this proportion have other symptoms at presentation suggestive of disease progression in addition to the LUTS [Table 1]. At presentation, bone pain (at 35.7%), paraparesis or paraplegia (at 10.2%) and hematuria (at 14.2%) which are some of the features of advanced disease have only improved minimally, if at all, when compared to reports from previous decades.[9],[10],[13] So far, uncomplicated LUTS do not appear to be enough indication yet to seek medical care by men.

Studies from LMIC report various durations of delay in seeking medical care by men experiencing LUTS.[24] Medical records from this review indicate that only about 28.0% of men experiencing symptoms suggestive of prostate cancer in this past decade presented within 3 months of onset of symptoms. As it were, about 50% of these men presented after 6 months of symptoms and above 25% presented after 12 months of symptoms. Compared to reports from previous decades, there may not have been any appreciable positive shift in seeking medical care by men who may have prostate cancer in southeast Nigeria. Moreover, within the past decade, findings from this review do not give the impression that observable progress has been made in the area of early presentation to tertiary medical care [Figure 1]. Although there exist reports from other regions of the world of varying degrees of shift for the better in prostate cancer presentation indices,[25],[26] unfortunately, reports from the regions of Nigeria are yet to show similar tendency.[27] Regrettably, awareness and practice of screening for prostate cancer may actually be poor among men in Nigeria and other LMIC.[28],[29] In comparison, recent studies on breast cancer and cervical cancer from some LMIC including Nigeria suggest a shift in favor of better cancer health indices.[19],[30]

Through the last decade, there are also no observed significant differences in the levels of serum tPSA [Figure 2] and the prostate biopsy GS [Figure 3] among these men presenting with symptoms leading to prostate cancer diagnosis. These findings support the observation that these men continue to present in the same manner they used to in the past despite the various attempts at improving on their capacity to present earlier with diseases that have better prognosis.[26] The short-term benefits reported from cancer awareness interventions are yet to translate into observed earlier presentations, or improved screening-based cancer diagnosis in this hospital. It is possible that limited capacity of primary care physicians to recognize promptly the need for appropriate referral as well as rudimentary referral system contribute to the absence of observable positive shift in prostate cancer presentation indices.[31] This observation does not however mean that no ground has been gained at all.[7] Gains reported with breast and other cancers from some health facilities suggest that instituted cancer awareness and empowerment programmes are rewarding.[30] However, there might be need to review the implementation strategies of these programmes, especially as it affects men, to ensure that the less educated, the poor of the poor, the poorly reached, and the media and internet information constrained, who probably form the study population of this review, are reached.


   Conclusions Top


It is conceivable therefore that regarding prostate cancer presentations in this public 3rd tier referral hospital, the last decade continued to witness high proportions of late presentation with complications of advanced diseases. Screening-diagnosed prostate cancer is almost nonexistent. Symptom duration at the presentation does not yet show measurable shift toward earlier presentation. Men continue to present late with features of advanced diseases, and without any positive shift in serum tPSA values and in prostate biopsy GS. It is therefore recommended that more effort be put toward providing appropriately structured information to men in the communities to increase their capacity to make right decisions favoring early prostate cancer diagnosis.

Acknowledgment

The authors express sincere gratitude to Augustine Okonkwo, Chuma Onyejizu, Uchechukwu Ogbobe, Nonso Ozoalor and Paschal Maduabuchi for their active roles in data retrieval.

Financial support and sponsorship

Nil.

Conflicts of interest

There are no conflicts of interest.



 
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