Multilocular cystadenoma and cystadenocarcinoma of the prostate

Urologic Oncology: Seminars and Original Investigations 25 (2007) 19 –25

Original article

Multilocular cystadenoma and cystadenocarcinoma of the prostate Tomasz Tuziak, M.D., Ph.D.a, Philippe E. Spiess, M.D., M.S.b, Neil A. Abrahams, M.D.a, Andrzej Wrona, M.D.c, Shi-Ming Tu, M.D.d, Bogdan Czerniak, M.D., Ph.D.a,* a

Department of Pathology, The University of Texas M.D. Anderson Cancer Center, Houston, TX 77030, USA Department of Urologic Oncology, The University of Texas M.D. Anderson Cancer Center, Houston, TX 77030, USA c Department of Urology, St. Luke’s Hospital, Tarnow, Poland d Department of Genitourinary Medical Oncology, The University of Texas M.D. Anderson Cancer Center, Houston, TX 77030, USA b

Received 29 September 2005; received in revised form 19 January 2006; accepted 20 January 2006

Abstract Background: Multicystic prostatic tumors are rare, with only a few reported cases of prostatic cystadenoma and cystadenocarcinoma in the scientific literature. Methods: A retrospective review of our tumor registry over the last 25 years identified 2 rare cystic tumors of the prostate: 1 multilocular cystadenoma and 1 multilocular cystadenocarcinoma. Results: The first case illustrates the clinical and pathologic features of prostatic multilocular cystadenoma. A 42-year-old man presented with a 16-cm suprapubic mass causing displacement of adjacent visceral organs. Pathologic examination after prostatectomy confirmed it to be a multilocular cystadenoma of the prostate. The patient’s postoperative course was uneventful, and his serum prostate-specific antigen level remained at ⱕ0.04 ng/ml throughout the course of his disease. In the second case, we present an 80-year-old male presenting with a 12-cm cystic mass of the prostate. His serum prostate-specific antigen level remained at ⱖ9.0 ng/ml throughout the course of his disease. The tumor had an aggressive local growth pattern, with invasion into perirectal adipose tissue. This patient underwent a pelvic exenteration, followed by adjuvant systemic chemotherapy and complete androgen blockade. Despite aggressive treatment, he had 3 recurrences over 4 months but remains alive with disease at 23-month follow-up. Conclusions: Cystadenocarcinoma of the prostate is locally aggressive and should be included in the differential diagnosis of cystic lesions of the prostate. © 2007 Elsevier Inc. All rights reserved. Keywords: Prostate; Cystadenoma; Cystadenocarcinoma

1. Introduction Cystic tumors of the female adnexa are common, and much is known about their evaluation and treatment [1]. However, cystic lesions of the male genitalia are extremely rare; only 12 cases of prostatic cystadenoma have been reported in the English literature [2-12]. To the best of our knowledge, there have been only 15 reported cases of the malignant counterpart of prostatic cystadenoma, termed cystadenocarcinoma [13-16]. Because of the rarity of prostatic papillary cystadenocarcinoma, there has yet to be established diagnostic histopathologic criteria required to make this diagnosis. As such, the aim of the current study * Corresponding author. Tel.: ⫹1-713-794-1025; fax: ⫹1-713-7924049. E-mail address: [email protected] (B. Czerniak). 1078-1439/07/$ – see front matter © 2007 Elsevier Inc. All rights reserved. doi:10.1016/j.urolonc.2006.01.011

was to highlight the distinguishing clinical and pathologic features differentiating prostatic cystadenoma and cystadenocarcinoma. In addition, a review of the scientific literature on papillary cystadenoma and cystadenocarcinoma addresses the differential diagnosis and treatment options for these conditions. 2. Materials and methods 2.1. Study design After obtaining approval from our institutional review board, we queried our tumor registry for prostate cancer cases (N ⫽ 7242) evaluated at the University of Texas M.D. Anderson Cancer Center from January 1, 1980, to December 31, 2004. Of these patients, we reviewed all cystic lesions of the prostate referred and/or treated at our institu-

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T. Tuziak et al. / Urologic Oncology: Seminars and Original Investigations 25 (2007) 19 –25

tion during this time. We identified 1 case of a multilocular cystadenoma and 1 multilocular cystadenocarcinoma. The clinical presentation, laboratory, and radiologic imaging of these patients were reviewed. The histopathologic slides with additional immunohistochemical stains were reevaluated. All patient identifiers were removed so that patient confidentiality could be maintained throughout the study.

ment. The patient received 4 cycles of systemic chemotherapy (carboplatinum and taxol) and was placed on complete androgen blockade (antiandrogen and luteinizing-releasing hormone agonist). At last follow-up, this patient remains alive with stable residual disease, as seen on abdominal CT at a follow-up of 23 months. The contrasting clinical and radiographic features of these 2 cases are presented in Table 1.

3. Results

3.2. Histopathologic evaluation

3.1. Clinical presentation

The lesion in case No. 1 was composed of cysts haphazardly dispersed in a hypocellular, fibrous stromal tissue (Fig. 1C). The lesion consisted of cystic structures of various sizes lined with low cuboidal cells, with basally located oval nuclei and no discernible nucleoli (Fig. 1D). Occasional residual normal prostatic acini were present between the cystically dilated glandular structures. No nuclear stratification, papillary structures, or cribriform formations were present. In the larger cysts, the epithelial lining was highly attenuated with the cells flattened against the cystic wall. Overall, the cells lining the cysts were strongly and uniformly positive for PSA and prostate acid phosphatase. Basal cells were identified on light microscopy and with immunohistochemical staining for high-molecular weight cytokeratin CK34␤E12 and cytokeratin 5/6 (Fig. 1E). In case No. 2, a lesion having a multilocular cystic architecture similar to cystadenoma was seen on low magnification (Fig. 2A). Nuclear stratifications, papillary structures, and so-called roman arch formations were seen in the cystically dilated glands (Fig. 2B). However, the epithelial lining of the cystic spaces consisted primarily of columnar glandular cells, with peribasally located nuclei with prominent nucleoli (Fig. 2C). These proliferations were seen predominantly in small-to-intermediate-sized cystic structures. Microscopically and immunophenotypically, the cells lining the cystic structures resembled prostatic luminal cells, and co-expressed PSA and prostate acid phosphatase (Fig. 2D). No basal cell layer was identified in the cystically dilated glands, either on light microscopy or with the assistance of CK34␤E12 and cytokeratin 5/6. An aggressive local growth pattern with infiltration of the cystically dilated glands into adjacent adipose tissue was readily apparent.

A previously healthy 42-year-old man presented with obstructive urinary symptoms and with 1 episode of urinary retention. Physical examination and computerized tomography (CT) revealed a 16-cm multicystic pelvic mass with lateral displacement of the urinary bladder (Fig. 1A). His preoperative serum prostate-specific antigen (PSA) level was 0.04 ng/ml. On examination of a biopsy sample, we found fibrous tissue with interspersed prostatic glands having no atypical features. An open prostatectomy without seminal vesicle removal was performed with complete removal of the tumor and negative surgical margins. Gross examination of the excised mass revealed it to be a 15-cm well-circumscribed multicystic tumor (Fig. 1B). On the basis of the overall cytoarchitectural features, a diagnosis of multilocular cystadenoma of the prostate was made. The second case was of a 76-year-old man presenting with bladder outlet obstruction. The clinical presentation was suggestive of benign prostatic hyperplasia, and transurethral resection of the prostate was performed. The specimen was described in the outside pathology report as consistent with stromal and glandular hyperplasia. The patient did not have any postoperative voiding difficulties and was completely asymptomatic for 2 years. Approximately 26 months after the initial surgery, the patient presented with rectal discomfort and a change in bowel habits. A physical examination and CT revealed a 12-cm cystic mass of the prostate, extending into the perirectal region (Fig. 2A). At surgery, the tumor was infiltrating into the perirectal soft tissue, with attachment to the posterior bladder wall. The tumor was incompletely resected with positive surgical margins. The resected portion of the tumor consisted of a large cystic mass. Within 2 months, the tumor had regrown to its original size and had accumulated a substantial amount of fluid, as seen on abdominal CT. After unsuccessful percutaneous drainage of the lesion, the patient was referred to our institution. Extensive surgical resection consisting of a pelvic exenteration was performed. Despite aggressive surgical treatment, the tumor was incompletely resected because it extended into the pelvic sidewall. This patient was presented at our multidisciplinary genitourinary rounds, and it was thought that this tumor was clearly malignant and should be treated with adjuvant treat-

4. Discussion In this report, we describe 2 cases of extremely rare cystic lesions of the prostate, with similar cytoarchitectural features but distinct clinical and pathologic characteristics. Both tumors consisted of multilocular cysts, however, their epithelial linings had distinctive features (Table 2). A single layer of cuboidal cells lined the cystic spaces of the cystadenoma, with nuclei presenting no atypia or prominent nucleoli. These cells were phenotypically similar to prostatic acinar columnar cells, which

T. Tuziak et al. / Urologic Oncology: Seminars and Original Investigations 25 (2007) 19 –25

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Fig. 1. (A) Abdominal/pelvic CT revealing a multicystic prostatic mass (16 ⫻ 12 cm highest dimensions). Prostatic mass did not extend into the pelvic sidewall. A delayed image of an intravenous pyelogram with severe hydronephrosis and hydroureter of the left kidney, as well as a very distended bladder secondary to bladder outlet obstruction from the prostatic cystadenoma is revealed (inset). (B) Gross photomicrograph of prostatic cystadenoma clearly showing multicystic composition of this lesion. Cystic composition of prostatic cystadenoma is clearly illustrated. (C) Low-power magnification of cystadenoma of the prostate, with cystic structures surrounded by a fibrous stroma and some residual prostatic acini (⫻40). (D) High-power magnification of epithelium lining the cystadenoma, consisting of low cuboidal cells with basally located oval nuclei (⫻400). (E) High-power magnification of the prostatic cystadenoma with positive cytokeratin 34␤E12 and cytokeratin 5/6 immunostaining (⫻400).

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Fig. 2. (A) Low-power magnification of prostatic cystadenocarcinoma having a similar multicystic architecture to the cystadenoma (⫻40). Abdominal/pelvic CT showing multicystic lesion further shown extending into the perirectal adipose tissue and a small calcification is shown within the mass (inset). (B) High-power magnification reveals the nuclear stratifications, papillary structures, and roman arch formations of cystadenocarcinoma (⫻100). (C) High-power magnification with the epithelial lining consisting of columnar cells with peribasal nuclei and prominent nucleoli (⫻400). (D) High-power microscopy with immunostaining for PSA (⫻400).

co-express PSA and prostate acid phosphatase. Peribasal cells were documented microscopically and immunohistochemically. In contrast, the cells lining the cystadenocarcinoma showed nuclear stratification, papillary proliferations, and roman arch structures. Nuclear enlargement and prominent nucleoli were uniformly present. In addition, peribasal cells were not seen by light microscopy or detected by immunohistochemical staining. The growth pattern of the cystadenocarcinoma was invasive, with haphazard destruction of intervening prostatic paren-

chyma and aggressive invasion into periprostatic adipose tissue. The benign cystadenoma showed expansile growth and was successfully treated with prostatectomy, with no evidence of recurrence 2 years postoperatively. In contrast, prostatic multilocular cystadenocarcinoma behaved in a malignant fashion, showing locally aggressive behavior, and destructively invading extraprostatic soft tissue and adjacent organs (i.e., the rectum and bladder). This tumor had a propensity for recurring locally as well,

T. Tuziak et al. / Urologic Oncology: Seminars and Original Investigations 25 (2007) 19 –25 Table 1 Summary of clinical and pathologic presentations of prostatic cystadenoma and cystadenocarcinoma Case No. 1

Case No. 2

Diagnosis

Prostatic cystadenoma

Clinical presentation (preoperative PSA) CT findings

Voiding obstruction (ⱕ0.04 ng/ml)

Treatment

Total excision of tumor and prostate without seminal vesicles

Outcome

Disease free at 2 years, no recurrences

Prostatic cystadenocarcinoma Voiding difficulties and perirectal pain (ⱖ9.0 ng/ml) Large multicystic mass in perirectal region with extension into lateral pelvic space Transurethral resection of the prostate, followed by pelvic exenteration Three recurrences and local growth into perirectal adipose tissue

Multilocular mass in prostate extending into suprapubic space

despite aggressive surgical and systemic treatment. Therefore, all evidence support the malignant nature of this tumor. Previous reports of multilocular prostatic cystadenomas have described large benign tumors with expansile noninvasive growth, making them amenable to surgical excision (Table 3). In all but 2 of the reported cases, total excision was successful with no recurrences. However, in the case reported by Maluf et al. [3], incomplete resection led to a recurrence that was successfully treated with pelvic exenteration, and in the case reported by Datta et al. [8], a recurrent tumor was treated with an luteinizing hormonereleasing hormone agonist. Of the previous reported cases of prostatic cystadenocarcinoma, 12 occurred in Japan [13,15,16]. The majority of patients presented between the ages of 60 and 80 years, with the most common clinical presentation being gross hematuria (33%) or bladder outlet obstruction (25%). As such, our patient presented with a common presentation of papillary cystadenocarcinoma. In the previously reported cases of prostatic cystadenocarcinoma [13], the mean diameter of these tumors at diagnosis was 7.5 cm (range 5–10), making our reported case 1 of the largest tumors treated. Most of the prior cases of prostatic cystadenocarcinoma presented at an advanced clinical stage (T3 or T4 in 75% of cases) and have been treated with radical surgery (e.g., radical prostatectomy, radical cystectomy, or pelvic exenteration) with adjuvant hormonal or chemotherapy. Despite aggressive therapy, these tumors have a propensity for local recurrence, as illustrated in our case. It is difficult, though, to suggest treatment options on the basis of such a few reported cases of cystadenocarcinoma. Nevertheless, we believe establishing the diagnosis early in the disease course combined with complete surgical resection may offer the best chance at long-term cancer control and potential cure. Similarly, there may be a benefit to neoad-

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juvant therapy as a method for shrinking the tumor before consolidative therapy. Of the previously reported cases of prostatic cystadenocarcinoma, 25% of patients have died of disease, making this tumor a frequently fatal condition, particularly in those unable to have local control. The differential diagnosis of cystic prostatic lesions includes several benign and malignant conditions. Atypical prostatic hyperplasia of phyllodes type presents as a large cystic lesion, but, unlike cystadenocarcinoma, it is composed of a highly proliferative prostatic epithelium and is accompanied by a hypercellular stroma. Spindled stromal cells, which may have enlarged atypical hyperchromatic nuclei, are of smooth muscle and fibrous origin. A focal myxoid change in the stroma can be seen [17-19]. Other prostatic cystic lesions that should be considered in the differential diagnosis include such non-neoplastic conditions as a utricular cyst (müllerian duct cyst), simple retention cyst of the prostate, diverticulum of the ejaculatory duct, seminal vesicle cyst, and bladder diverticulum [17,2026]. All these lesions share a common multilocular appearance, and, histologically, the cysts are lined by flattened, prostatic, glandular, transitional-type epithelia. Seminal vesicle cysts are usually unilateral and unilocular. They are lined by either flattened or papillary epithelia, with pigment and intranucleolar inclusions characteristic of seminal vesicle epithelia [17,22,23]. Mesothelioma and lymphangioma are extraprostatic neoplasms that present as multicystic lesions, but their histologic features and immunohistochemical profile differ substantially from those of the lesions we have described. In mesothelioma, the epithelioid cells lining the cysts are CK34␤E12 and PSA negative [27,28]. In contrast, these tumors are positive for cytokeratin 5/6 and calretinin. The cystic spaces in lymphangioma are lined with attenuated cells that are cytokeratin negative but

Table 2 Summary of histologic features of multilocular prostatic cystadenoma and cystadenocarcinoma Microscopic feature Low magnification Cyst formation Hypocellular stroma Flat epithelium Papillary structures Cribriform structure Infiltrating borders High magnification Clear cytoplasm Basophilic cytoplasm Nuclei stratification Nucleoli Basal cell layer Immunohistochemistry PSA CK34␤E12 ⫹ ⫽ present; ⫺ ⫽ absent.

Cystadenoma

Cystadenocarcinoma

⫹ ⫹ ⫹ ⫺ ⫺ ⫺

⫹ ⫹ ⫺ ⫹ ⫹ ⫹

⫹ ⫺ ⫺ ⫺ ⫹

⫺ ⫹ ⫹ ⫹ ⫺

⫹ ⫹

⫹ ⫺

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Table 3 Summary of cases of prostatic cystadenoma reported in the literature between 1991 and 2003

Maluf et al. [3]

Year

1991

No. of cases

Patient age (yrs)

Clinical symptoms

Laboratory tests

Location

CT/MRI findings

2

28

Acute urinary retention

NA

Extraprostatic

NA

38

Difficulty in micturition

NA

Extraprostatic/pelvic extending to abdominal cavity Extending to pelvic cavity Prostatic/extending to pelvic cavity

NA

Microscopy

4 Months, no recurrences

19 cm/600 g

Flattened epithelium, low-grade nuclei, no nucleoli, papillary and cribriform architecture

2 Years, local recurrence NA

45 cm/6500 g

1 Year, no recurrences

12.5 cm/130 g

NA

17 cm/g, NA

Flat epithelium

Multiseptate thickened walls Cystic mass

8 Years, no recurrences 11 Years

13 cm/g, NA

Papillary structures

12 cm/g, NA

Multiloculated cystic pelvic mass

NA

14 cm/g, NA

Columnar cells, back to back glandular growth, rare mitoses Atrophic epithelium, foci of high-grade PIN

18 Months

15 cm/g, NA

2000

1

57

Dysuria

NA

Kirsch et al. [4]

1996

1

65

Obstructive voiding, hematuria

PSA 30.2 ng/ml

Lim et al. [5]

1993

1

64

Lower abdominal pain

NA

Levy et al. [6]

1993

1

56

Polyuria

Datta et al. [8]

2003

1

71

Urinary retention

PAP ⬍0.9 ng/ml PSA 33 ng/ml

Allen et al. [7]

2003

1

52

PSA 3 ng/ml

Rusch et al. [11]

2002

2

30

2 ng/ml

Pelvic mass

Multiple septations

41

Lower urinary tract symptoms, gross hematuria Urinary retention, lower urinary tract symptoms Acute urinary retention

Prostatic and seminal vesicle/ midline Extraprostatic later a pelvic extension Pelvic mass between prostate and bladder Pelvic mass

Pelvic mass

35

Gross hematuria

14.4 ng/ml

Multiseptated cystic mass Multilocular mass

2002

1

Prostate

Pathology Gross

Choi et al. [2]

Matsumoto et al. [12]

Follow-up

Multiseptate thickened irregular walls Heterogenous/ multiloculated mass Fluid-filled mass

MRI ⫽ magnetic resonance imaging; NA ⫽ not available; PAP ⫽ prostate acid phosphatase; PIN ⫽ prostatic intraepithelial neoplasia.

15 cm/300 g

Flattened epithelium, squamous metaplasia Cuboidal to low columnar cells

Cuboidal and lowcolumnar epithelial cells

15 cm/g, NA NA

9 cm/860g

Dilated glands with prostatic epithelium

T. Tuziak et al. / Urologic Oncology: Seminars and Original Investigations 25 (2007) 19 –25

Investigator

T. Tuziak et al. / Urologic Oncology: Seminars and Original Investigations 25 (2007) 19 –25

react to anti-endothelial antibodies, such as CD31 [29-31]. The 2 cases we report provide a comparison of cystic tumors of the prostate having similar but yet distinct clinical and pathologic features. Multilocular cystadenocarcinoma of the prostate should be considered in the differential diagnosis of a cystic prostatic lesion, particularly if this tumor is locally aggressive and has a propensity for local recurrence.

5. Conclusions In the present study, we report 2 rare cystic tumors of the prostate, termed multilocular cystadenoma and cystadenocarcinoma. Both these tumors have distinguishing clinical and pathologic features that must be considered when establishing their diagnosis. Furthermore, cystadenocarcinoma of the prostate is a locally aggressive tumor with a propensity for local recurrence, therefore placing much importance on the adequacy of surgical resection, with the role of neoadjuvant and adjuvant therapy yet to be defined.

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