Prostate adenocarcinomas aberrantly expressing p63 are molecularly distinct from usual-type prostatic adenocarcinomas.

We have described a rare group of prostate adenocarcinomas that show aberrant expression of p63, a protein strongly expressed in prostatic basal cells and absent from usual-type acinar prostate cancers. The partial basal-like immunophenotype of these tumors is intriguing in light of the persistent debate surrounding the cell-of-origin for prostate cancer; however, their molecular phenotype is unknown. We collected 37 of these tumors on radical prostatectomy and biopsy and assessed subsets for a diverse panel of molecular markers. The majority of p63-expressing tumors were positive for the ΔNp63 isoform (6/7) by immunofluorescence and p63 mRNA (7/8) by chromogenic in situ hybridization. Despite p63 positivity, these tumors uniformly expressed luminal-type cytokeratin proteins such as CK18 (13/13), CK8 (8/8), and markers of androgen axis signaling commonly seen in luminal cells, including androgen receptor (10/11), NKX3.1 (8/8), and prostein (12/13). Conversely, basal cytokeratins such as CK14 and CK15 were negative in all cases (0/8) and CK5/6 was weakly and focally positive in 36% (4/11) of cases. Pluripotency markers including ß-catenin, Oct4, and c-kit were negative in p63-expressing tumors (0/11). Despite nearly universal expression of androgen receptor and downstream androgen signaling targets, p63-expressing tumors lacked ERG rearrangements by fluorescence in situ hybridization (0/14) and ERG protein expression (0/37). No tumors expressed SPINK1 or showed PTEN protein loss (0/19). Surprisingly, 74% (14/19) of p63-expressing tumors expressed GSTP1 protein at least focally, and 33% (2/6) entirely lacked GSTP1 CpG island hypermethylation by bisulfite sequencing. In contrast to usual prostatic adenocarcinomas, prostate tumors with p63 expression show a mixed luminal/basal immunophenotype, uniformly lack ERG gene rearrangement, and frequently express GSTP1. These data strongly suggest that p63-expressing prostate tumors represent a molecularly distinct subclass and further study of this rare tumor type may yield important insights into the role of p63 in prostatic biology and the prostate cancer cell-of-origin.

Squamous neoplasia of the scrotum: a series of 29 cases.

The current epidemiology and clinicopathologic features of squamous cell carcinoma (SCC) of the scrotum are largely unknown because of its low incidence. We describe the histopathologic features, immunohistochemistry, and human papillomavirus (HPV) status of 29 patients with scrotal SCC. The mean age at presentation was 55 years (range, 30 to 74 y). White to black ratio was 1.9:1. There was no predominant occupation, with the majority being white-collar professionals. Clinical history of condylomas was present in 5 patients, and 7 patients had a history of multiple skin cancers including melanoma, basal cell carcinoma, and other SCCs. Other comorbidities included human immunodeficiency virus infection (n=2), kidney transplant (n=1), leukemia/lymphoma (n=2), hidradenitis suppurativa (n=1), chronic scrotal infections with abscess (n=1), inflamed epidermal inclusion cyst (n=1), and lichen planus (n=1). One patient had a history of regular tanning bed use. Morphologically, the majority was usual type (n=17), followed by basaloid (n=7) and warty (n=5). Nineteen cases were in situ, and 10 were invasive. Three patients had inguinal lymphadenopathy; in 1, metastasis was confirmed. Suprabasal nuclear staining for Ki67 was considered positive. For p16, a continuous band of nuclear and cytoplasmic staining was considered positive, and a noncontinuous or absence of staining was considered negative. p16 was positive in 10 cases; high-risk HPV was confirmed in 7 cases. Ki67 was positive in 8/17 (47%) usual, 6/7 (85.7%) basaloid, and 3/5 (60%) warty type. p53 was positive in 5/17 (29.4%) usual, 2/7 (28.6%) basaloid, and 1/5 (20%) warty type. All patients were treated with local excision only; 13 had positive margins. Three patients were treated with imiquimod after local excision. The median follow-up was 30 months. Three patients recurred and were treated with re-excision; 1 patient received radiotherapy. Overall, the morphologic, immunohistochemical, and HPV studies show that, similar to SCC of the vulva or penis, the SCC of the scrotum can be divided into 2 major groups. Group 1 (38.5%): positive for p16 and elevated Ki67. This group is associated with HPV infection and displays predominantly a basaloid or warty morphology, although a number of them are of usual type. Group 2 (61.5%): negative for p16. This group has variable Ki67 expression, is consistently negative for HPV, and displays predominantly usual-type morphology. SCC of the scrotum in the United States currently affects primarily white-collar professionals. The majority present with in situ lesions, and the high rate of positive margins at first excision suggests that they are clinically ill-defined lesions. No longer are occupational exposures to carcinogens the major etiology of scrotal SCC. Rather in contemporary times, common risk factors include HPV infection, immunocompromised states, and chronic scrotal inflammatory conditions.

Aberrant expression of p63 in adenocarcinoma of the prostate: a radical prostatectomy study.

Prostatic adenocarcinoma with aberrant diffuse expression of p63 (p63-PCa) is a recently described variant of prostatic adenocarcinoma. The aim of this study was to investigate the clinical and pathologic features of p63-PCa at radical prostatectomy (RP). We reviewed 21 cases of p63-PCa diagnosed on needle biopsy at subsequent RP. Immunohistochemical analysis for PIN4 and Ki-67 was performed in all RP cases. p63-PCa showed a distinctive morphology consisting of atrophic, poorly formed glands, with multilayered and often spindled nuclei. Gleason grading was 3+3=6 in 28.5%, 3+5=8 in 38%, 3+4=7 in 14.3%, and 4+3=7, 5+3=8, and 5+4=9 in 9.5%. Usual-type acinar carcinoma coexisted in 85.7% with only p63-PCa present in the remaining cases. The usual-type carcinoma was Gleason grade 3+2=5 in 4.7%, 3+3=6 in 57%, 3+4=7 in 19%, and 4+3=7 in 4.3%. Overall, p63-PCa represented 65% of the total cancer volume (median 80%). The tumor was organ-confined in 16 cases (76.2%). In the remaining 5 cases, 2 had p63-PCa extending to the margin in areas of intraprostatic incisions, 2 had usual-type acinar adenocarcinoma extending to the margin and extraprostatic tissue, respectively, and 1 had p63-PCa with an unusual cribriform morphology involving the bladder neck. Ki-67 was low, <5% in all cases of p63-PCa, with similar expression in the coexisting acinar-type carcinoma. In summary, it is recommended that these tumors not be assigned a Gleason score and their favorable findings at RP be noted.

Prostatic stromal neoplasms: differential diagnosis of cystic and solid prostatic and periprostatic masses.

OBJECTIVE: The objectives of this article are to illustrate the radiologic-pathologic correlation of prostate stromal neoplasms and to review the imaging appearances of cystic and solid prostatic and periprostatic masses that may mimic prostatic stromal neoplasms. CONCLUSION: The differential diagnosis for cystic and solid masses in the prostate is broad, and masses arising from periprostatic structures may mimic the appearance of primary prostatic diseases. Attention to clinical and imaging features is helpful in narrowing the differential diagnosis.

Nephrogenic adenoma: a report of 3 unusual cases infiltrating into perinephric adipose tissue.

Nephrogenic adenoma of the urinary bladder, where they present most frequently, are typically confined to the lamina propria but can on occasion focally involve the superficial muscularis propria. Less commonly, nephrogenic adenoma involves the renal pelvis and ureter where again they almost always only involve the lamina propria. We identified 3 consult cases in which tubules of nephrogenic adenoma extensively involved the muscularis propria and focally infiltrated the perinephric adipose tissue, for which the contributing pathologists considered the diagnosis of adenocarcinoma. In 1 case, that of a 71-year-old man, the lesion was associated with a hemorrhagic renal cyst (3.0 cm) and a spontaneous retroperitoneal bleed (6.0 cm) of unknown origin. In the second case, that of a 73-year-old woman, 2 foci (2.2, 1.6 cm) were present in the renal pelvis. They developed after biopsy of a low-grade noninvasive papillary urothelial carcinoma in the same site complicated by perforation. The third case was that of a 20-year-old woman with ureteropelvic junction obstruction and severe hydronephrosis associated with renal calculi. In all cases, the lesions were positive for CK7 and PAX8. These 3 cases report the novel finding that nephrogenic adenoma can occasionally have a deep infiltrative pattern into perinephric adipose tissue, possibly as a result of either biopsy-associated perforation or extensive disruption due to hemorrhage or mechanical obstruction. Awareness of this worrisome infiltration pattern, although rare, can prevent a misdiagnosis of an infiltrating carcinoma.

Massive localized lymphedema of the male external genitalia: a clinicopathologic study of 6 cases.

Massive localized lymphedema is a reactive pseudotumor strongly associated with obesity. The tumor most commonly presents as pendulous masses in the lower limbs with only 3 reported cases involving external male genitalia. In this study, we report an additional 6 cases localized to the external male genitalia. The cases were retrospectively identified from the surgical pathology database of the Johns Hopkins Hospital. All 6 patients were obese (5 presented with diffuse scrotal edema and 1 with a penile mass). In all cases, the clinical impression was of a benign chronic process developing over 3 months to 1 year. All 3 cases from outside institutions were referred with benign pathologic diagnoses. The lesions ranged in size from 4 to 55 cm. Microscopically, all cases exhibited stromal fibrosis and edema, multinucleated stromal cells, perivascular chronic inflammation, and lymphangiectasia. Entrapped fat was a minor feature and seen in only 3 cases. Variable hyperplasia and hypertrophy of dartos muscle were noted in 6 lesions. Three cases showed prominent microvascular proliferation around the edge of individual dartos muscle bundles. In summary, diagnosis of massive localized lymphedema requires appropriate correlation between clinical and microscopic findings. Lesions in the male external genitalia share many microscopic findings with massive localized lymphedema at other sites, although entrapped adipose tissue is not prominent. Additional, although not specific, findings include variably hyperplastic and hypertrophic dartos muscle and capillary neoangiogenesis at the interface between smooth muscle bundles and stroma.

Small cell-like change in prostatic intraepithelial neoplasia, intraductal carcinoma, and invasive prostatic carcinoma: a study of 7 cases.

Small cell carcinoma of the prostate is associated with poor prognosis and different treatment from conventional acinar adenocarcinoma. Given the important clinicopathologic implications of a diagnosis of small cell carcinoma, we report 7 cases showing unusual, extensive small cell-like change in intraductal carcinoma and invasive carcinoma. Prostatic biopsies from 3 patients and radical prostatectomy specimens from 4 patients showed variably extensive small cell-like high-grade prostatic intraepithelial neoplasia and intraductal carcinoma. Five cases were associated with conventional acinar adenocarcinoma (2 cases with Gleason score 4 + 3 = 7; 3 cases with Gleason 3 + 4 = 7). No small cell carcinoma was seen. Small and large ducts with small cell-like change showed solid and cribriform proliferations of atypical cells with abrupt transition between centrally located populations of small cells and more typical large dysplastic cells at the duct periphery. Rosette-like formations were noted within some involved ducts. Small cell-like change was characterized by crowded cells with uniformly bland vesicular nuclei and minimal cytoplasm and no significant mitotic or apoptotic activity. In 3 cases, similar small cell-like morphology was noted focally in invasive carcinoma. The small cell-like areas were negative for synaptophysin and chromogranin, focally positive for TTF-1, and weakly positive for racemase. Ki-67 labeled less than 5% with predominant labeling of the larger atypical cells and minimal reactivity in the small cell-like population. In summary, small cell-like change in prostatic intraepithelial neoplasia, intraductal carcinoma, and invasive carcinoma is not associated with small cell carcinoma; shows no immunohistochemical evidence of neuroendocrine differentiation; and likely is not an adverse prognostic feature.

Do adenocarcinomas of the prostate with Gleason score (GS) ≤6 have the potential to metastasize to lymph nodes?

Although rare, there are cases within reported series of men with Gleason score (GS) ≤6 on radical prostatectomies that show pelvic lymph node (LN) metastases. However, there are no studies on whether pelvic LN metastases occur in tumors with GS ≤6 using the International Society of Urological Pathology (ISUP) updated GS system. We performed a search of the radical prostatectomy databases at 4 large academic centers for cases of GS ≤6. Only prostatectomies submitted and embedded in entirety with pelvic LN dissections were included. A combined total of 14,123 cases were identified, of which 22 cases had a positive LN. Histopathologic review of 19 cases (3 cases unavailable for review) showed higher grade than originally reported by the pathologists in all cases. Of the 17 pre-ISUP reviewed cases, 2 were upgraded to 4+3=7 with both cribriform and poorly formed glands. One case was upgraded to 4+3=7 with tertiary pattern 5 displaying cribriform glands, poorly formed glands, and cords of single cells. Eleven cases were upgraded to 3+4=7 with glomeruloid structures and small to large cribriform glands (1 of these also had features of ductal adenocarcinoma). Two cases had tertiary pattern 4 with small cribriform glands. One case had a prominent colloid component that would currently be graded as 4+5=9 because of large cribriform glands and solid sheets of cells within the mucin. Of the 2 post-ISUP cases, 1 demonstrated tertiary pattern 4, and the other showed GS 3+4=7 with irregular cribriform glands. Undergrading is the primary reason for LN positivity with GS ≤6, which has decreased significantly since the adoption of the ISUP grading system in 2005. Of over 14,000 totally embedded radical prostatectomies from multiple institutions, there was not a single case of a GS ≤6 tumor with LN metastases. In contrast to prevailing assumptions, GS ≤6 tumors do not appear to metastasize to LNs. Rather, Gleason pattern 4 or 5, as better defined by the current ISUP updated grading system, is required for metastatic disease.

Fibrolamellar carcinomas are positive for CD68.

Fibrolamellar carcinomas are a unique type of liver carcinoma that arise in non-cirrhotic livers of young individuals. Despite their distinctive appearance, recent studies have demonstrated a lack of consistency in how fibrolamellar carcinomas are diagnosed by pathologists. As a potential aide in diagnosis, we investigated the staining properties of CD68. The CD68 gene encodes for a transmembrane glycoprotein located within lysosomes and endosomes. Macrophages as well as other cell types rich in lysosomes/endosomes are CD68 positive. Cases of fibrolamellar carcinoma were collected from four academic centers. Control groups included hepatocellular carcinomas arising in both non-cirrhotic livers and cirrhotic livers. A group of cholangiocarcinomas were also stained. CD68 immunostaining was scored for both intensity and distribution on a scale of 0 to 3+. Twenty-three primary fibrolamellar carcinomas and 9 metastases (total of 24 individuals) were immunostained and showed a distinctive granular, dot-like or stippled pattern of cytoplasmic staining in nearly all cases (31/32), with a median distribution and intensity score of 3+. In control hepatocellular carcinomas that arose in non-cirrhotic livers, 10/39 showed CD68 staining with a median distribution and intensity score of 2+. In hepatocellular carcinomas arising in cirrhotic livers, 3/27 cases showed CD68 positivity, all with stippled dot-like cytoplasmic staining similar to that of fibrolamellar carcinomas. All five cholangiocarcinomas were negative. Overall, CD68 positivity was strongly associated with fibrolamellar carcinomas, P<0.001 and had a sensitivity of 96%, a specificity of 80%, and a negative predictive value of 98%. In sum, tumor positivity for CD68 staining was highly sensitive for fibrolamellar carcinoma and a lack of CD68 staining should suggest caution in making a diagnosis of fibrolamellar carcinoma.

Intestinal spirochetosis in children: five new cases and a 20-year review of the literature.

Intestinal spirochetosis (IS) is an unusual infection in children, one with no standard therapeutic options. This article reports the findings on 5 new cases in conjunction with a 20-year review of the pediatric literature. The diagnosis of IS in children requires a high degree of suspicion by the physician, as many cases present with abdominal pain, chronic diarrhea, and/or hematochezia associated with a normal endoscopic examination. Silver stains (Dieterle or Whartin-Starry) are the preferred confirmatory stains on tissue sections. Giemsa (Diff-Quik) and periodic acid-Schiff stains may also be of value. Current literature favors the use of metronidazole in adult patients with IS, yet little information is available regarding treatment options in pediatric cases. This review indicates that a macrolide antibiotic with or without metronidazole may represent the best therapeutic choice for children. Further investigations are needed to determine the correlation between IS and coexisting gastrointestinal diseases and/or immunodeficiencies.