Prostate Gland in Human Foetuses: A Study of its Histogenesis

Background: To study the histogenesis of the prostate gland in human foetuses. ‘Prostates’ is a Greek word which literally means “one who stands before”, protector, guardian. It is important from a clinical point of view as it undergoes benign enlargement from the fifth decade, hence attracting the attention of males around this age and simultaneously the clinicians. Materials and Methods: 100 foetuses of different gestational ages ranging from 14 weeks (85 mm) to 40 weeks (440 mm), products of terminated pregnancies under Medical Termination of Pregnancy, MTP Act of India, 1971 and stillbirths were collected from the Department of Obstetrics and Gynaecology, RIMS, (Regional Institute of Medical Sciences), Imphal, Manipur and utilised for the present study with permission from the Institutional Ethical Committee. Results and Discussion: The first sign of differentiation is recognised as increased cellularity and denser mesenchymal cells. Cytoarchitecture at specific age period at different age groups are described. Conclusion: Cytoarchitecturally, differentiation of all the three components of the prostate gland was noted as the age changes. It is inferred that of the three components of the adult tissues, the glandular component is differentiated from the epithelial lining of the urethra. This further induces the early mesenchymal tissues to differentiate into muscles and fibrous components. And at term, it has all the three components of the adult tissues although it is not as mature as in adult.

Modulatory effects of Saccharomyces cerevisiae var. boulardii on experimentally induced benign prostatic hyperplasia in rats

Benign prostatic hyperplasia (BPH) is an age-related non-neoplastic disease of the prostate gland in men that has become a global health issue in recent years. Due to the side effects of conventional treatment options, attention is now focused on phytotherapeutics for its management. We investigated the possible protective effect of Saccharomyces cerevisiae var. boulardii in a rat model of testosterone propionate (TP) induced BPH. Rats were divided into five groups: Gr. I, untreated control group; Gr. II, TP group; Gr. III, TP + finasteride; Gr. IV, TP + S. cerevisiae var. boulardii; and Gr. V, S. cerevisiae var. boulardii group. Treatments were given daily for 28 days. At the end of the experiment, all rats were weighed and the prostatic indices, prostate specific antigen, serum testosterone concentration as well as the histological and histomorphometric changes were evaluated. Saccharomyces cerevisiae var. boulardii significantly (P <0.05) reduced prostate weight, prostatic index, serum prostate specific antigen, prostatic epithelial thickness and increased luminal diameter. Thus, the results of this study suggest that S. cerevisiae var. boulardii is a potential pharmacological candidate for management of benign prostatic hyperplasia.

Ultra Sonographic Prostate Volume Measurement of Patients Over 40 Years in Age: A Single Center Study

Background: Benign prostatic hyperplasia (BPH), also called prostate enlargement, is a noncancerous increase in size of the prostate gland. Symptoms may include frequent urination, trouble starting to urinate, weak stream, inability to urinate, or loss of bladder control. The objective of the study was to evaluate the prostate volume measurement for the Bangladeshi population over the age of 40 years by ultrasonography.Material & Methods:This prospective, observational study was conducted in the Department of Anatomy, Chattogram International Medical College (CIMC), Chattogram, Bangladesh during the period from January 2019 to December 2020. In total 157 suspected patients of benign prostatic hyperplasia were selected as the study population. All patients were clinically diagnosed for BPH, based on the present prostate symptoms and digital rectal examination. To measure the prostate volume, abdominal ultrasonography was performed for all the patients. After enucleation, another ultrasonogram was performed for all the patients to measure the existing sizes of the prostates of the patients. All the data were processed, analyzed, and disseminated by MS-word and SPSS programs as per need.Results:Finally, in this study in analyzing the volumes of the prostates of the participants according to the abdominal ultra-sonographic reports of pre-operative stage we observed, in 9%, 34%, 31%, 30%, 21% and 32% patients, the prostate sizes (In cc) were <20, 21-40, 41-60, 61-80, 81-100 and >100 cc respectively. On the other hand, after enucleation, in 11.46%, 24.20%, 28.66%, 27.39%, 7.01% and 1.27% patients, the prostate sizes (In cc) were found <20, 21-40, 41-60, 61-80, 81-100 and >100 cc respectively. The mean changes of prostate sizes between pre- and post-operative stages among the participant was not significant where the P value was found 0.464.Conclusion:The findings of this study support the applications of abdominal ultrasonographic evaluation for suspected benign prostatic hyperplasia patients to know about the exact volumes of their prostates for selecting the appropriate surgical approach.

Effectiveness of transabdominal ultrasonography in assessing benign versus malignant nature of prostatomegaly

Background: Benign prostatic hyperplasia is closely related with ageing. The present study was conducted to assess the ability of transabdominal ultrasonography in diagnosing benign and/or malignant hypertrophy of the prostate.Methods: An observational study was done in the Department of Radiology, Bharati Vidyapeeth Medical College and Hospital (Deemed to be University), Sangli, Maharashtra, India of patients who had prostatomegaly on transabdominal ultrasound examination and underwent histopathological confirmation of the lesions from 1 October 2018 till 31 December 2018. The prostate gland was assessed for volume, echotexture, morphology, focal lesions and median lobe.Results: Out of 155 patient’s benign prostatic disease was diagnosed in 116 patients, while malignancy was detected in the rest of the 39 cases. Prostate specific antigen levels were significantly higher among malignant cases (18.39±7.44 ng/ml) as compared to that of benign cases (7.51±3.22 ng/ml), p value <0.01. Benign lesions were predominantly inner glandular, while malignant cases were mainly peripheral. Moderate vascularity was found in 76.9% of the malignant cases. Focal vascular asymmetry was found in 74.4% of the malignant cases and only 12% of the benign cases. Sensitivity of transabdominal ultrasonography in diagnosing malignant prostatic lesions was 94.8%, specificity was 75% with an overall accuracy of using transabdominal ultrasonography in the diagnosis of malignant prostatic lesions in this study population was 80%.Conclusions: Transabdominal ultrasound evaluation of prostate is a simple, economical, non-invasive technique of choice due to its high accuracy in detecting size, nature of pathology as benign or malignant with fair accuracy.

Transvesical Prostatectomy Versus Transurethral Resection ofProstate For Treatment of Benign Prostatic Hyperplasia More Than 100 Gms: A Randomized Control Trial

Purpose: To compare the functional effects and complicationsof transvesical prostatectomy (TVP) and bipolar transurethralresection of prostate (TURP) in patients with benign prostatichyperplasia (BPH) more than 100 gms.Method: Hundred and five patients participated at the SPMCMedical College, Bikaner, India with complaints of BPH withprostate size of 100-150 gm over study duration from June2015 to May 2018. Patients were grouped according to theireligibility for the two surgical procedures namely TVP (n=56)and bipolar TURP (n=49).Results: Of the total 105 patients, 56 (53.33%) patients weresurgically treated with TVP while the remaining 49 (46.67%)were managed with TURP. We did not observe any statisticallysignificant difference between the two groups with regards theIPSS, Qmax, residual urine volume. The numbers of postoperative complications were higher in TURP group (n=9) ascompared to TVP (n=3). Even the late complications such asstricture formation, need for redoing the surgery were higher inTURP group compared to TVP group.Conclusion: Open prostatectomy is a safer and more effectivesurgical treatment option for patients with BPH more than 100gms as compared to bipolar TURP. Even the reports of postoperative complications were higher in TURP group.

Morphogenesis Of The Prostate Gland In Human Foetuses

Background: To study the morphogenesis of the prostate gland in human foetuses. ‘Prostates’ is a Greek wordwhich literally means “one who stands before”, protector, guardian. It is important from a clinical point of viewas it undergoes benign enlargement from the fifth decade,hence attracting the attention of males around this ageand simultaneously the clinicians.Materials and Methods: 112 foetuses of different gestational ages ranging from 14 weeks (85 mm) to 40 weeks(440 mm), products of terminated pregnancies under MTP Act of India, 1971 and stillbirths were collected fromthe Department of Obstetrics and Gynaecology, RIMS, Imphal and utilised for the present study with permissionfrom the Institutional Ethical Committee.Results and observations: The first time of appearance of the prostate gland to the naked eye till its definitiveadult shape is studied. Growth and development at specific age period at different age groups are described.Conclusion: Increase in vertical and transverse dimensions, assumption of adult shape were noted as the agechanges.And at term,it has all the three components of the adult tissues although it is not as mature as inadult.This signifies that the growth of the prostate continues postnatally.

Monosodium Glutamate Induced Oxidative Stress In Accessory Reproductive Organs Of Male Sprague-Dawley Rats / Jurnal Sains Kesihatan Malaysia

Monosodium glutamate (MSG) is widely used as a food additive but its excessive intake leads to oxidative stress of severalorgans. However, the oxidative effect of MSG on male accessory reproductive organs remains unclear. Therefore, theaim of this study was to evaluate the effect of MSG on the status of oxidative stress and morphological alterations in themale accessory reproductive organs such as epididymis, prostate glands and seminal vesicle of Sprague-Dawley rats.A total of 24 male Sprague-Dawley rats were randomly divided into three groups with 8 rats per group. Control groupreceived distilled water (1 ml/kg) while MSG60 and MSG120 received 60 mg/kg and 120 mg/kg of MSG, respectively.All the substances were administered via force feed oral for 28 consecutive days. At the end of the study, the rats weresacrificed to obtain the accessory organs for biochemical analysis and histological observations. The SOD activity in theepididymis showed a significant increase in MSG60 and MSG120 compared to control (p < 0.05). The GSH levels in theepididymis of MSG 120 showed a significant reduction (p < 0.05) compared to the control group. The levels of MDA andPC in the epididymis and prostate gland of MSG60 and MSG120 showed a significant increased (p < 0.05) comparedto the control group. Histological alterations were found in the epididymis and prostate gland of MSG treated rats. Inconclusion, MSG at both doses induced oxidative stress in the epididymis and prostate gland of experimental rats.

Multi-parametric 3-Tesla MRI evaluation of prostate in cases with negative prostatic biopsy with raised PSA levels – A tertiary care hospital study

The incidence of prostate cancer has been gradually increasing in the world. Checking the serum prostate-specific antigen (PSA) level and a digital rectal examination (DRE) are the gold standards for prostate cancer screening. Prostate gland is divided into four zones, the peripheral zone (PZ), transitional zone and central zone and anterior nonglandular fibromuscular stroma. Prostate is divided into minimum 16 and optionally 27 regions of interest as per European consensus meeting. Until recently, most professionals have been skeptical that magnetic resonance imaging (MRI) could be used on a widespread basis to diagnose or stage prostate cancer with any degree of reliability, and therefore help with making treatment decisions. The aim of the present study was to study diagnostic value of mpMRI of prostate in cases of raised PSA but with negative biopsy. The present study was carried out in the post graduate department of Radiodiagnosis and imaging Govt. Medical College Srinagar over a period of one year from May 2016 to April 2017. All patients with negative prostatic biopsy were evaluated on Siemens 3 tesla MRI scanner. All patients underwent initial T1W scanning to look for any evidence of hemorrhage and patients having hemorrhage due to previous biopsy were also excluded from study or their study was deferred until hemorrhagic artifacts disappear. After proper case selection patients were subjected to detail Multiparametric MRI (mpMRI) for prostate 6-8 weeks period was given from previous biopsy time to MRI study and cases with hemorrhage on T1 weighted sequence were either excluded from study or their study was deferred till resolution of Aijaz Ahmad Hakeem, Irshad Mohiuddin, Tanvir Iqbal. Multi-parametric 3-Tesla MRI evaluation of prostate in cases with negative prostatic biopsy with raised PSA levels - A tertiary care hospital study. IAIM, 2018; 5(6): 5-13. Page 6 haemorrhage. The conclusion of the present study was that Mp-MRI prior to repeat biopsies can improve the detection rate of clinically significant PCa and allow for a more accuracy in prostate disease diagnosis.

Robot-assisted laparoscopic radical prostatectomy on a very large prostate gland

@#This is a case of a 74-year-old obese male presented with moderate lower urinary tract symptoms and an elevated prostate specific antigen (PSA) of 48.21ng/ml. Multiparametric MRI of the prostate revealed a markedly enlarged prostate (225grams) with a PIRADS 5 lesion at the left posterior peripheral zone. Prostate biopsy done revealed prostate adenocarcinoma Gleason 7(3+4). Metastatic workup was negative for distant metastasis hence the patient was advised robot-assisted laparoscopic prostatectomy (RALP).Several difficulties were encountered during the surgical technique. The usual posterior approach was not feasible because incising the peritoneum over the rectovesical pouch would not be able to expose the vas deferens and seminal vesicles. An anterior approach was instead done, but this was still difficult due to the lack of space for proper exposure and movement of instruments. The posterior dissection was also challenging; three successive suspension stitches were necessary in order to expose and mobilize the lateral and posterior surface of the prostate. Urethrovesical anastomosis had to be modified by performing a modified posterior repair in order to reduce tension caused by the large gap left by the excised prostate. RALP is a safe and feasible operative technique for very large prostates as long as the difficulties are foreseen and the necessary adjustments are made.Robot-assisted laparoscopic prostatectomy (RALP) has emerged as the preferred option in the treatment of localized prostate cancer. As more cases are being performed, more surgeons are encountering challenging cases, such as those with difficult anatomy, prior abdominal surgery and prior radiation therapy. Large prostate glands increase the technical difficulty of performing robot-assisted laparoscopic prostatectomy.1 Reported is a case of RALP in a patient with prostate size >200. The difficulties and concerns in such situations are also delineated.

Radiological Profile of Patients with Benign Prostate Hypertrophy.

Background: As TRUS-guided prostate biopsy is associated with significant complications, preventing unnecessary biopsies becomes very important. TRUS-guided prostate biopsies also raise the diagnostic rate of clinically insignificant prostate cancer. Objective: To study the radiological profile of patients with benign prostatic hyperplasia. Methods: A hospital based cross sectional study was carried out among 40 patients. Their informed consent was obtained. The patients were referred from Urology department. Digital rectal examination and trans rectal ultrasonography was performed for all patients. The results were expressed as percentages. Results: 24 patients were in the age group of 51 to 71 years. The least age group subjected to in the study was the patients below the age of 40 years. 35% of the patients studied in the present study had diffuse enlargement of the prostate. In addition, it can be observed that 65% of the patients studied in the present study had focal nodular benign prostatic hyperplasia. Conclusion: Benign prostatic hyperplasia was found common in the elderly patients.

Biochemical Changes in Albino Rats Exposed to Rice Husk Dusk at Abakaliki Rice Mill Industrial Area.

The effect of rice husk dust inhalation on some biochemical parameters was conducted on albino rats. Method: 100 albino rats were divided into five groups with each group containing twenty albino rats. Group A served as the control and were housed at the animal house away from rice dust while group B, C, and D were exposed to rice husk dust for two week, three weeks and four weeks respectively for dust inhalation. They were allowed access to rats feeds and deionized water ad libitium. Blood samples were collected from each group at the end of exposure by cardiac puncture. Glucose level was determined using the glucose reagent kit, acid phosphatase concentration was performed using reagent kits, creatinine and uric acid concentration was determined spectrophotometrically, the weight of the rats were recorded daily. Results: Result showed significant reduction in body weight of the exposed. The glucose level decreased significantly while the serum acid phosphatase and serum uric acid level showed a significant increase. Histological result showed various degrees of damage to the kidney of the exposed rats. Conclusion: We therefore conclude that rice husk dust inhalation induces glucose depletion, injury to the kidney and prostatic glands in the albino rat and impairs the renal function.

Cytokeratin-positive primitive neuroectodermal tumor of the prostate: Case report and review of literature.

Ewing's sarcoma/primitive neuroectodermal tumor (ES/PNET) of the prostate is extremely rare. Here, we report a case of ES/PNET of prostate in a 24-year-old man presenting with dysuria and pelvic discomfort. Computed tomography scan revealed a heterogeneous mass involving the prostate without evidence of distant metastases. Histologically, the tumor was composed of small round blue cells strongly and diffusely positive for CD99 and epithelial markers. Fluorescence in situ hybridization confirmed rearrangement of the Ewing's sarcoma region on chromosome 22.

Gross anatomical, histological and histochemical studies on the postnatal development of the prostate gland of Gaddi goat / Estudios anatómicos macroscópicos, histológicos e histoquímicos sobre el desarrollo postnatal de la glándula prostática de la cabra Gaddi

The study was conducted on the prostate gland of Gaddi goat from one day old to more than five years of age divided into three groups viz; prepubertal (1 day old to < 18 months of age), pubertal (18 months to < 5 yrs of age) and postpubertal (> 5 yrs of age). The prostate comprised of corpus prostatae, a band like structure close to the junction of vesicular gland with the urethra, and the pars disseminate which extended in urethra well from its origin to the point of duct of bulbourethral gland. Microscopically, the corpus prostatae comprised of two compact glandular masses lying one over the other, dorsally over the origin of pelvic urethra covered by a thick fibro-reticular capsule. The gland composed of end pieces (luminated and non-luminated acini) and ducts arranged in lobulated fashion. The thickness of inter and intralobular connective tissue decreased with increased age at the expense of the growth of paraenchyma. With age the luminated secretory end pieces increased, while the non-luminatedend pieces decreased in the lobules of the gland. Glandular parenchyma were rich in mucous components by 6 month age serous and mucous components became almost equal and at 12 month age majority of the secretory end pieces turned in to serous type. The excretory ducts which were lined by stratified cuboidal epithelium in one day old kids changed to transitional epithelium in late prepubertal and pubertal animals. The glandular elements were PAS and Best's carmine reactive while interstitial connective tissue was non reactive. Mild alkaline phosphatase reaction was evident in the interstitial connective tissue cells. A strong acid phosphatase reaction was evident in the endothelium. BPB reaction for protein was moderate to intense. Ducts and acini were PAS and Alcian Blue reactive. The reaction for glycogen and AMPS contents in the gland increased with age. It was very intense in the pubertal animals. Moderate DNA activity, mild to moderate alkaline and acid...

Se realizó un estudio de la glándula próstatica de la cabra Gaddi, desde el día uno de nacimiento hasta después de los cinco años de edad, divididos grupos prepuberal (1 día a 18 meses de edad), puberal (18 meses a <5 años de edad) y post-púberes (más de 5 años de edad). La próstata estaba constituida por un cuerpo prostático, estructura como una banda cercana a la unión de la glándula vesicular con la uretra, y una pars diseminada la cual se extendía en las paredes de la uretra desde su origen hasta el punto de los conductos de la glándula bulbouretral. Microscópicamente, el cuerpo prostático está compuesto por dos masas compactas glandulares situadas una sobre la otra, dorsalmente sobre el origen de la uretra pélvica cubierta por una gruesa cápsula fibro-reticular. La glándula compuesta por piezas terminales (acinos luminal y no luminal) y conductos dispuestos en forma lobulada. El espesor del tejido conectivo inter e intralobulillar disminuyó con el aumento de la edad a expensas del crecimiento del parénquima. Con la edad aumentaron las piezas terminales secretoras luminales, mientras que en las piezas terminales no luminales, disminuyeron en los lóbulos de la glándula. El parénquima glandular era abundante en componentes mucosos a la edad de 6 meses, mientras que los componentes serosos y mucosas se equilibraron a los 12 meses de edad; la mayoría de las piezas finales secretoras se transformaron a tipo serosa. Los conductos excretores que estaban revestidos por epitelio cúbico estratificado en el día uno de las crías, cambió a epitelio de transición en los animales prepúberes y púberes. Los elementos glandulares fueron reactivos al PAS y al carmín de Best, mientras que el tejido conectivo intersticial no fue reactivo. Una reacción leve a la fosfatasa alcalina fue evidente en las células del tejido conectivo intersticial, mientras que una reacción fuerte se evidenció en el endotelio. La reacción de BPB para proteína fue de moderada a intensa. Los conductos...

Morphology of the male agouti accessory genital glands (Dasyprocta prymnolopha Wagler, 1831) / / Morfologia das glândulas genitais acessórias em cutias (Dasyprocta prymnolopha Wagler, 1831)

The morphology of the accessory genital glands of the male agouti was studied in twenty-three animals that were raised in captivity. Twenty animals had their genital glands dissected in situ for macroscopic description. The samples of each gland were recovered, embedded in paraffin, sliced and stained by Hematoxylin-Eosin technique. It was founded four pairs of glands: the vesicular glands, the coagulating glands, the prostate and the bulbourethral glands. Histological characteristics of the vesicular, coagulating and prostate glands showed similar morphology, within the pseudostratified columnar epithelium. The tubulo-alveolar type of the bulbourethral glands showed a lack of connective tissue among the tubules, a small amount of red stained presented it the cytoplasm, and the presence of vacuoles in the tissue. This study concluded that the agouti showed to have similar morphological aspect described in the others species of rodents.

A morfologia das glândulas genitais acessórias de cutias foram estudados em 23 animais criados em cativeiros. Vinte animais tiveram suas glândulas genitais dissecadas in situ para as descrições macroscópicas. Para o estudo microscópico foram utilizados três animais. Os fragmentos de cada glândula foram embebidos em parafina, seccionados e corados em hematoxilina e eosina. Foram encontrados quatro pares de glândulas: vesiculares, coaguladoras, próstata e bulbouretrais. As características histológicas da glândula vesicular, coaguladora e próstata mostraram morfologia similar, com epitélio colunar pseudoestratificado. O tipo tuboalveolar da glândula bulbouretral mostrou uma deficiência de tecido conjuntivo, citoplasma pouco corado e presença de vacúolos. Este estudo concluiu que a cutia apresenta as mesmas características morfológicas das glândulas genitais acessórias encontradas em roedores.

Adenocarcinoma of the Prostate Gland Accompanied by Primary Small Cell Carcinoma of the Bladder / 대한비뇨기과학회지

Small cell carcinoma in the urinary bladder is very rare. There are only a handful of cases reported in the medical literature to date. A case of a primary bladder small cell carcinoma, detected by magnetic resonance imaging(MRI) during a follow up examination of a 77-year-old male patient who visited the outpatient clinic of our institution initially complaining of voiding difficulties and diagnosed with adenocarcinoma of the prostate gland with a Gleason score of 10 is, herein, reported. (Korean J Urol 2007;48:1092-1095)

Therapeutic Effect of Urinary Retention due to Hyperplasis of Prostate Gland by Combining Electric Acupuncture to Ciliao and Zhongliao Acupoints with Ultrashort Wave Therapy / 浙江中医药大学学报

[Objective ] To evaluate the curative effect of urinary retention caused by hyperplasia of prostate gland after treatment of electric acupuncture to Ciliao and Zhongliao acupoints combined with ultrashort wave therapy.[Methods] 35 patients were treated by electric acupuncture to Ciliao and Zhongliao acupoints cooperating with ultrashort wave therapy.Residual urine volumn(RUV),frequency of urinary retention,the therapeutic effect and follow-up were recorded and statistically analyzed.[Results] 29 patients were able to urinate after the therapy,except for 6 patients who were still in urinary retention condition.Effective rate were up to 82.8%.[Conclusion] It proved that the less the frequency was,the better the clinical effect would be.However,no matter how frequent the retention was,our combination therapy still worked,and both effects of the near future and long-term were proved to be fine.Special therapeutic action from Shu acupoint,electric acupuncture's electric current effect,and physical therapy of ultrashort wave contributed to the outcome.

Clinical experience of professor YANG Mu-xiang in treating intractable disease by brunellae spica / 中华中医药杂志

Clinical experience of professor YANG Mu-xiang in treating hypertension,hyperplasia of prostate gland,acne and thyroid hyperfunction by brunellae spica were introduced,it was considered that the taste of brunellae spica was bitter and sweet,which was not hurt the spleen and stomach,and its cold nature was not consumption of yang,and it could remove hepatic heat,and have the function of eliminating stagnation.It was used when position of disease was liver,and pathogenesis was stagnation of liver qi or accumulation of heat;the dosage of 10-15g was used when the cooling-relieving heat accumulation therapy,and the dosage of 15-30g was used when eliminating stagnation.

Ewing's sarcoma arising in prostate gland: A case report.

An 18-year-old Thai male presented with weight loss and urinary retention. Physical examination revealed an enlarged prostate gland. Serum prostate specific antigen (PSA) level was 0.3ng/ml. Histologic section demonstrated a small round cell tumor with intracytoplasmic glycogen. Immunohistochemical and ultrastructural studies were compatible with Ewing's sarcoma. Since no other osseous or extraosseous lesions of the same tumor were found in this patient, we concluded that this was a case of primary extraskeletal Ewing's sarcoma of the prostate gland. Case follow-up after one year revealed a good response to chemotherapy.

Adenoid cystic carcinoma of the prostate gland: pathological review with a case report

A case of adenoid cystic carcinoma of the prostate gland in a 38-year-old Korean man is described. Microscopically, variable patterns, that is, glandular, trabecular, cribriform and solid areas, were seen. The unusual location of this tumor in our patient highlights the ubiquitous distribution of this malignant neoplasm.