Prostatic Leiomyosarcoma: The Case for Combined Modality Therapy

Patient. A 65-year old man who had previously undergone surgery for benign prostatic hyperplasia presented with symptoms of recurrent bladder outflow obstruction. Cystoscopy revealed the presence of recurrent tissue. Results. Histology identified a leiomyosarcoma. Several years after further surgery and radiotherapy, the patient presented with secondaries in the lungs and brain, but there was no evidence of local recurrence. Discussion. It is suggested that combined modality therapy (conservative surgical resection followed by adjuvant radical radiotherapy) be the initial treatment for prostatic leiomyosarcoma.


Introduction
Leiom yosarcom a of the prostate is a rare, highly m alignant tumour, that occurs predom inantly in adults. Less than 100 cases in adults have been published. W e report another case and review the literature. The natural history of the tum our is characterized by rapid growth, and eventually wide dissem ination to the lungs, brain, bone and liver. T he prognosis remains poor regardless of therapy, w ith all patients dying of dissem inated disease w ithin a few years of the diagnosis. A review of the literature over the past few decades suggests that radical surgical treatm ent is the m ost com m only advocated therapeutic modality. Com plete excision in m ost cases, however, is extremely dif® cult, comm only followed by recurrence, and rarely results in cure. W e suggest, for patients with localized prostatic leiomyosarcom a, com bined m odality therapy in the form of conservative prostatic surgical resection, followed by adjuvant radical radiotherapy, as the initial treatment. Radical surgery should be reserved only for local failure and in the absence of distant m etastasis.

P atient
A 65-year-old m an presented with symptoms of recurrent bladder out¯ow obstruction. He had undergone transurethral resection of the prostate 6 years previously for benign prostatic hyperplasia. Exam ination revealed a benign-feeling prostatic enlargement and cystoscopy revealed an encroachm ent of the prostatic cavity by recurrent tissue. Further resection w as perform ed and histology identi® ed a leiomyosarcom a. Further ultrasound and CT scan for staging failed to show any evidence of disease outside of the prostate. Radical prostatectomy was advised but the patient declined. Accordingly, a radical course of radiotherapy was adm inistered to the prostate gland after a further deep resection of the prostate cavity.
The patient rem ained well for 3 years when he presented with dyspnoea on exertion. Chest X-ray and CT of the chest showed m ultiple m etastases consistent with secondaries from sarcoma of the prostate. H e received chem otherapy for palliation but a few m onths later he developed a headache and C T con® rm ed secondaries in the brain. Four years after the diagnosis, there was no evidence of local recurrence, but the patient died of disseminated disease in the lung and brain.

D iscussion
Prostatic sarcom as are extremely rare, constituting 0.1± 0.2% of primary prostatic neoplasm s. Prostatic leiom yosarcom a (PL) is the second most com m on prostatic sarcom a (after rhabdom yosarcom a) and accounts for m ost cases in adults with a m edian age at diagnosis of 58 years. 1 In the majority of cases, there is no clear aetiology but previous pelvic radiotherapy has been incrim inated in som e cases. 2

S. El-Sharkawi & K. Vaughton
Inkeeping with our patient, the m ost com m on presenting sym ptom s are those of bladder neck out¯ow obstruction. Other sym ptom s include pelvic pain, haem aturia and constipation.
It is im possib le to m ake the diagnosis of PL by rectal exam ination as the ® ndings are often of a sm ooth ® rm enlargem ent of the prostate.
In view of the rarity of PL, the diagnosis is often unsuspected at the time of presentation, and like all sarcom as, the im portance of app ropriate biopsy and opinion of an experienced pathologist in the diagnosis cannot be over-em phasized. 3 U ltrasound is a useful prelim inary investigation, but C T scan or m agnetic resonance im aging are very im portant, not only for evaluating the prim ary site but also in determ ining the presence or absence of m etastasis and assessm ent of response to treatment.
Proper m anagem ent of PL depends on sound knowledge of its pathology, biology and natural history, and is best achieved by close collaboration between pathologist, urologist and oncologist. T he disease rem ains localized for a variab le period of time before it spreads locally to the bladder, rectum or perineum , or to a distant location in the lungs, brain, bone and liver, hence the im portance of early diagnosis and treatment.
PL is a highly m alignant tum our for which curative therapy rem ains elusive. Because of its rarity, it is not clear from the literature whether surgery, radiotherapy, chem otherapy or a com bined m odality treatm ent offers the greatest hope. O ver the last few decades, these therapeutic m odalities have been attempted separately and in various com binations but none resulted in cure. 4± 6 In patients with poor survival prospects like that of PL, regardless of the therapeutic modality, the aim of the treatment m ust be to achieve and m aintain local control of the prostatic disease as long as possible with m inim um m orbidity. On reviewing the literature, radical surgical excision w as the m ost frequently and perform ed therapeutic m odality. 4,5 There is little evidence, however, that it has any curative value in the m anagement of PL. In addition, it is associated with signi® cant physical and psychological m orbidity. C heville et al. described 11 patients who underw ent curative radical surgery for localized PL: ® ve of them had gross residual tumour, ® ve experienced local recurrence 2± 41 m onths after surgery, and one patient had no evidence of recurrence 4.5 m onths after surgery. 4 M ottola et al. described two patients w ith PL w ho died 13 and 20 m onths after radical surgery due to recurrence. 7 Russo et al. reported a patient with PL who died of m etastatic disease soon after radical surgery. 8 T hese cases are consistent w ith the experience and results of other authors. 9,10 T hey all indicate that PL is frequently aggressive.
PL in general has a high propensity for local recurrence and distant spread. T his m ay be related in part to the delay in diagnosis and presentation. In the 1970s, the concept of using lim ited surgical excision with adjuvant radical radiotherapy (combined m odality therapy) was introduced in the m anagement of soft tissue sarcom as, and its value has been demonstrated in several sites and at different centres. 11± 13 Ahlering et al. reported the outcom e of four patients with PL treated with com bined m odality therapy (surgical resection and radical radiotherapy): three of them were alive w ith no residual disease at 60, 73 and 87 months follow-up. 14 O ur patient rem ained recurrence free for 3 years, then died after 4 years of disseminated disease in the lungs and brain. Locally, how ever, there was no evidence of recurrence of his PL. Our experience with this case is consistent with the experience of others that PL is frequently aggressive but occasionally it takes an indolent course. 4 The encouraging results using conservative surgery and radical radiotherapy (com bined m odality therapy) require further national or international study of the role of com bined modality therapy in the m anagement of PL.