Macrofollicular variant of papillary thyroid carcinoma with metastasis to femur.

BACKGROUND: Macrofollicular variant of papillary thyroid carcinoma (MFV-PTC) is a rare subtype with histological features and an indolent clinical course that can be confused with nodular goiter or follicular adenoma. However, on rare occasions it may show more aggressive biological behavior. Only two cases of MFV-PTC with bone metastases have been reported previously. We describe the clinical-pathological characteristics of a man with MFV-PTC that developed femur metastasis. This the first case of MFV-PTC with femur metastases diagnosed histologically by means of an image-guided core needle biopsy in English literature. CASE PRESENTATION: A 33-year-old man presented two years earlier with swelling in the right neck associated with weight loss and pain in the left knee. Neck ultrasonography showed hyperechogenic and hypogenic nodular images in the thyroid's right lobe. A fine needle aspiration biopsy specimen was initially interpreted as nodular hyperplasia. A CT showed a large tumor involving right thyroid lobe with trachea and vascular structures displaced to the right, and a total thyroidectomy was performed. Subsequently, a MRI of the knee confirmed the presence of a destructive tumor in the femur. A guided core-needle biopsy of the knee tumor showed the presence of metastatic MFV-PTC. Re-assessment of the histology from thyroidectomy was also consistent with MFV-PTC. A whole-body 18F-FDG PET/CT showed presence of lesions in the left anterior costal arch, metaphysis of the left femur and in the sternum handle. Therefore, he received 200 mCi radioactive iodine, and 40 Gy of radiotherapy to left costal arches and knee, which decreased his symptoms. Currently, after 10 months of follow-up, the patient is alive with bone tumor activity. CONCLUSIONS: Our case supports the view that, on rare ocassions, MFV-PTC may show a more aggressive biological behavior than expected. The synchronous or asynchronous presence of one or more bone lesions, should raise the suspicion of metastasis. Given the suspicion, it is necessary to take a biopsy to confirm histologically. Only a careful analysis of the architectural and cytological characteristics of goiter or hyperplastic nodules will allow to recognize this rare variety of carcinoma.

Atrophic and Microcystic Limited Prostatic Adenocarcinomas.

Atrophic carcinoma and microcystic carcinoma have previously been classified as variants of conventional acinar adenocarcinoma. In this article, we studied 4 cases of atrophic carcinoma and 4 cases of limited microcystic carcinoma. We found an incidence of 0.8% in 250 needle prostatic biopsies and 1.3% of atrophic carcinoma in 150 radical prostatectomies. Microcystic carcinomas were found in 3 prostatectomies (1.2%) and in 1 needle biopsy (0.67%). The useful histological criteria for atrophic carcinoma included the irregular disposition of the glands, infiltrative pattern, "rigid" luminal borders, and intraluminal secretions. Cytological changes included scant cytoplasm, nucleomegaly, hyperchromatic nuclei, and visible nucleoli. The glands of the microcystic carcinoma differ from the benign glands because the malignant ones show a markedly greater dilatation and exhibit rigidity of glandular lumens. In some cases of microcystic carcinoma, the nuclei were flattened, small, and hyperchromatic; therefore, they can be difficult to recognize as malignant.

Minimal (Limited) Pseudohyperplastic Prostatic Adenocarcinoma in Needle Prostatic Biopsy.

BACKGROUND: Study of minimum adenocarcinoma has been done almost exclusively on conventional acinar adenocarcinoma. Pseudohyperplastic adenocarcinoma can be confused with benign lesions because of its well-differentiated appearance and has not been studied when the biopsy shows few malignant glands (limited carcinoma). METHODS: We reviewed 94 pseudohyperplastic adenocarcinomas diagnosed in prostatic biopsies for a period of 12 years and selected those measuring less than 1 mm or involving less than 5% of the biopsied tissue. We also reviewed 200 consecutive consultations. RESULTS: Four (4.2%) of the 94 cases were limited pseudohyperplastic adenocarcinomas, and 3 were from consultations. Three of them were mistaken for hyperplastic nodules, prostatic adenosis, or prostatic intraepithelial neoplasm. The number of glands varied between 6 and 50 (average 23). Three nodular histological patterns were identified-nodular, adenosis-like, and pseudohyperplastic carcinoma resembling prostatic intraepithelial neoplasia. The diagnosis of adenocarcinoma was not related to the number of neoplastic glands. Histological criteria that were useful included: crowded medium to large glands, papillary infoldings, branching glands, straight luminal borders, hyperchromatic nuclei, nucleomegaly, and apparent nucleoli. Areas of transition to conventional acinar adenocarcinoma were useful in recognizing four of these neoplasms, but were barely apparent in 2 of them. Hyperchromatic nuclei were found in all cases, whereas apparent nucleoli and nucleomegaly were only present in 4. CONCLUSIONS: The architectural and cytological criteria for limited acinar adenocarcinoma are only partially useful in interpreting minimum pseudohyperplastic adenocarcinomas. Knowledge of the criteria for malignancy in both neoplasms is important in order to avoid underdiagnosis of malignancy.

Low grade urothelial carcinoma mimicking basal cell hyperplasia and transitional metaplasia in needle prostate biopsy.

PURPOSE: The vast majority of urothelial carcinomas infiltrating the bladder are consistente with high-grade tumors that can be easily recognized as malignant in needle prostatic biopsies. In contrast, the histological changes of low-grade urothelial carcinomas in this kind of biopsy have not been studied. MATERIALS AND METHODS: We describe the clinicopathologic features of two patients with low-grade bladder carcinomas infiltrating the prostate. They reported dysuria and hematuria. Both had a slight elevation of the prostate specific antigen and induration of the prostatic lobes. Needle biopsies were performed. At endoscopy bladder tumors were found in both cases. RESULTS: Both biopsies showed nests of basophilic cells and cells with perinuclear clearing and slight atypia infiltrating acini and small prostatic ducts. The stroma exhibited extensive desmoplasia and chronic inflammation. The original diagnosis was basal cell hyperplasia and transitional metaplasia. The bladder tumors also showed low-grade urothelial carcinoma. In one case, the neoplasm infiltrated the lamina propria, and in another, the muscle layer. In both, a transurethral resection was performed for obstructive urinary symptoms. The neoplasms were positive for high molecular weight keratin (34BetaE12) and thrombomodulin. No metastases were found in either of the patients, and one of them has survived for five years. CONCLUSIONS: The diagnosis of low-grade urothelial carcinoma in prostate needle biopsies is difficult and may simulate benign prostate lesions including basal cell hyperplasia and urothelial metaplasia. It is crucial to recognize low-grade urothelial carcinoma in needle biopsies because only an early diagnosis and aggressive treatment can improve the prognosis for these patients.

Low grade urothelial carcinoma mimicking basal cell hyperplasia and transitional metaplasia in needle prostate biopsy

ABSTRACT Purpose The vast majority of urothelial carcinomas infiltrating the bladder are consistent with high-grade tumors that can be easily recognized as malignant in needle prostatic biopsies. In contrast, the histological changes of low-grade urothelial carcinomas in this kind of biopsy have not been studied. Materials and Methods We describe the clinicopathologic features of two patients with low-grade bladder carcinomas infiltrating the prostate. They reported dysuria and hematuria. Both had a slight elevation of the prostate specific antigen and induration of the prostatic lobes. Needle biopsies were performed. At endoscopy bladder tumors were found in both cases. Results Both biopsies showed nests of basophilic cells and cells with perinuclear clearing and slight atypia infiltrating acini and small prostatic ducts. The stroma exhibited extensive desmoplasia and chronic inflammation. The original diagnosis was basal cell hyperplasia and transitional metaplasia. The bladder tumors also showed low-grade urothelial carcinoma. In one case, the neoplasm infiltrated the lamina propria, and in another, the muscle layer. In both, a transurethral resection was performed for obstructive urinary symptoms. The neoplasms were positive for high molecular weight keratin (34BetaE12) and thrombomodulin. No metastases were found in either of the patients, and one of them has survived for five years. Conclusions The diagnosis of low-grade urothelial carcinoma in prostate needle biopsies is difficult and may simulate benign prostate lesions including basal cell hyperplasia and urothelial metaplasia. It is crucial to recognize low-grade urothelial carcinoma in needle biopsies because only an early diagnosis and aggressive treatment can improve the prognosis for these patients.

Pseudohyperplastic Adenocarcinoma With Foamy Changes in Needle Prostate Biopsy and Prostatectomy.

Pseudohyperplastic adenocarcinoma (PHA) with foamy changes is composed of neoplastic glands that show a cytoarchitectural combination of both neoplasms. However, none of the previously reported cases have shown typical areas of foamy or PHA. We report on the clinicopathological characteristics of 5 cases consisting predominantly of pseudohyperplastic and foamy adenocarcinomas. In several histological fields, this neoplasm mimicked hyperplastic nodules or prostatic adenosis because they showed the nodular pattern of the PHA and the inconspicuous cytological atypia of foamy gland carcinoma. Four cases had a Gleason score of 6. In the prostatectomies, the neoplasm was limited to the prostatic gland. The evolution has been favorable in all patients after 3 years of follow-up, on average. The cases reported herein demonstrate that PHA and foamy adenocarcinoma may be associated and occasionally show overlapping histological criteria. The PHA with foamy changes must be distinguished from conventional foamy adenocarcinoma and PHA because it can closely resemble hyperplastic glands mainly in needle prostatic biopsy.

Pseudohyperplastic prostate carcinoma: histologic patterns and differential diagnosis.

The similarity between some carcinomas and many benign glandular proliferations has been mentioned in the literature for decades. The description of the main histologic features of pseudohyperplastic carcinoma has been very useful in avoiding errors of interpretation, particularly false-negative results. In recent years, we have found some histologic variants of this neoplasm that have not been mentioned previously. In order to classify the different histologic growth patterns and comment on their differential diagnosis, we reviewed the architectural and cytologic features of 34 cases of pseudohyperplastic adenocarcinoma in 2 radical prostatectomies, 4 transurethral resections, and 28 needle biopsies. Growth patterns most commonly observed included nodular, complex, and mixed (nodular and complex) patterns. Other less frequent histologic varieties included adenosis-like pattern, prostatic intraepithelial neoplasia-like pattern, pseudohyperplastic adenocarcinoma with xanthomatous features, and limited pseudohyperplastic adenocarcinoma. Frequent changes in neoplastic glands included papillary infoldings, large/cystic glands, and branching. Criteria associated with malignancy include nuclear enlargement (92%), apparent nucleoli (85%), pink amorphous secretions (78%), and transition to small acinar carcinoma (70%). However, in some biopsies, nuclear atypia was little apparent. Fifteen of the 34 cases were misdiagnosed as benign and 5 as other malignant neoplasms, and included the following diagnoses: hyperplastic nodules (11), prostatic adenosis (2), diffuse adenosis of the peripheral zone (1), benign cystic glands (1), and less frequently other malignant tumors including xanthomatous carcinoma (2), low-grade prostatic adenocarcinoma (2), and atrophic carcinoma (1). It is important to recognize the different growth patterns of this neoplasm in order to avoid an underdiagnosis of malignancy.

Atypical small acinar proliferation: utility of additional sections and immunohistochemical analysis of prostatic needle biopsies.

BACKGROUND: In surgical pathology, atypical small acinar proliferation is commonly detected in prostate biopsies. Most studies on atypical small acinar proliferation have examined morphological characteristics and the utility of immunohistochemical studies. However, these resources are not available to many pathology departments. We have found that examining additional sections is a simple and inexpensive method that allows better evaluation of focal prostatic glandular atypia. OBJECTIVES: The present report compares the diagnostic utility of immunohistochemical techniques versus examining additional sections in prostate biopsies with focal glandular atypia. PATIENTS AND METHODS: Thirty recently studied prostate biopsies with focal glandular atypia were selected. In each case, 3 additional levels were examined. An immunohistochemical study was performed on one level using an antibody against high-molecular-weight keratin (34BetaE12). Two additional sections were stained with hematoxylin and eosin. RESULTS: The diagnosis of focal carcinoma was established with only additional sections in 4 cases (13.3%). In 2 of these biopsies, additional areas of carcinoma were found that were not identified in the original sections. In 4 other cases, immunohistochemical analysis was the only useful method for diagnosing cancer. In 9 cases (30%), both methods were useful for classifying focal glandular atypia as carcinoma. In the remaining 13 cases,neither immunohistochemical analysis nor additional sections were useful in changing the diagnosis of focal glandular atypia. CONCLUSIONS: Focal glandular atypia in prostatic needle biopsies should be routinely examined with additional sections, particularly when immunohistochemical analysis is not possible. Some biopsies with atypical glandular proliferation may show focal carcinoma in additional sections, even if the immunohistochemical analysis did not provide a diagnosis of malignancy. Additional sections can also reveal areas of carcinoma that were not apparent in the original sections.

Pseudohyperplastic prostatic carcinoma in simple prostatectomy.

Pseudohyperplastic carcinoma (PHPC) is a prostatic neoplasm that can be easily mistaken for nodular hyperplasia or atypical adenomatous hyperplasia. To determine the frequency and clinicopathologic characteristics of PHPC, we reviewed 200 simple prostatectomy specimens. We found 3 cases (1.5%) of PHPC. The tumors were small and ranged in size from 4 to 6 mm. Two of them were erroneously diagnosed as benign glandular proliferations in the original interpretation. Their histologic aspect at low magnification showed nodules of well-differentiated medium-sized glands with cystic dilation in a tight arrangement that imparted a benign appearance. Corpora amylacea were found in 2 cases. However, the lining cells showed nucleomegaly and prominent nuclei in most of the neoplastic glands, and the high-molecular-weight keratin (34BE12) immunostain revealed absence of basal cells. α-Methylacyl-CoA-racemase was positive in 2 cases. In one case, a small focus of moderated acinar adenocarcinoma was found adjacent to the pseudohyperplastic glands facilitating the diagnosis. The 3 patients are disease-free 3 and 4 years after surgery probably because of the small size of the tumors; however, it must be emphasized that most PHPC are considered moderately differentiated and potentially aggressive neoplasms.

Neuroendocrine metastatic tumors of the liver resembling hepatocellular carcinoma.

Certain neuroendocrine tumors (NET) metastasized to the liver can resemble hepatocellular carcinoma (HCC) in cytological needle biopsy. Experience concerning the histologic characteristics of metastatic NET resembling HCC in core needle hepatic biopsies has been scarce. The aim of this study is to describe the histological criteria in seven metastatic NET that resembled HCC in core needle hepatic biopsy. From a total of 285 needle biopsies with primary or metastasized hepatic neoplasms, seven cases were selected originally diagnosed as HCC or HCC vs. NET metastasized to the liver. Fourteen needle biopsies of hepatocellular carcinomas were also studied for comparative purposes. In all of these neoplasms the diagnosis of endocrine tumor was confirmed by immunohistochemical studies and the following information was recorded: age, sex, radiological alterations, primary site of the NET, and follow-up. The following histological data were also recorded: fibrotic stroma associated or not with the neoplastic cells, growth pattern, form of the cells, cellular size, mitotic figures, nucleomegaly, apparent nucleoli, chromatin in salt and pepper, plasmacytoid cells, intranuclear inclusions, and biliary pigment. In conclusion, these characteristics were common in metastasized neuroendocrine tumors: extensive stromal fibrosis, slight to moderate atypia, hyperchromatic nuclei, plasmacytoid cells, and thin delicate strands of fibrovascular tissue supporting larger acinar groups of net cells. HCC had a more infrequent fibrotic stroma, moderate to marked atypia, and in some biopsies biliary pigment, intranuclear inclusions, and clear cells.

Early gastric cancer in Menetrier's disease.

Uncommon conditions such as pernicious anaemia and hypertrophic gastropathies have been considered as risk factors for gastric cancer; however, the exact increase in risk is unknown. Menetrier's disease is a rare hyperproliferative disorder of the stomach caused by an overexpression of tumour growth factor α, a ligand for the tyrokinase epidermal growth factor receptor, resulting in a selective expansion of surface mucous cells in the body and fundus of the stomach. There have been nearly 200 cases of Menetrier's disease reported in the literature yet less than 15 have been associated with gastric adenocarcinoma. Here, we report an early stage gastric adenocarcinoma detected incidentally in a patient recently diagnosed with Menetrier's disease.

Foamy gland microcarcinoma in needle prostatic biopsy.

Foamy gland carcinoma is an uncommon variant of prostatic carcinoma. Foamy microcarcinoma of the prostate has not been studied in detail in needle biopsy. We describe here useful criteria for the diagnosis of foamy gland microcarcinoma of the prostate in needle biopsy. We reviewed 6 cases of foamy gland microcarcinoma. All tumors measured less than 1 mm and involved less than 5% of the biopsied tissue. A range of 4 to 40 foamy neoplastic glands were found in the 6 tumors. The original diagnosis of foamy gland microcarcinoma was made in 3 cases. They were composed of 21 to 40 glands lined by cuboidal to columnar cells with abundant foamy cytoplasm and small picnotic nuclei. Infiltrating and nodular patterns were readily identified, and absence of basal cells was shown by cytokeratin stains. The remaining 3 cases were designated as atypical foamy glands and consisted of similar but fewer glands (4-20). The diagnosis of foamy gland microcarcinoma was not made because of lack of nucleomegaly and prominent nucleoli and because an infiltrating pattern was less apparent. Subsequent biopsies confirm the diagnosis of microcarcinoma. The number of glands lined by voluminous foamy cells with hyperchromatic nuclei, an infiltrating pattern, and the absence of basal cells with high-molecular-weight cytokeratin were the most useful features in the diagnosis of foamy microcarcinoma. The presence of few atypical foamy glands in needle biopsy requires detailed analysis because they may represent foamy gland microcarcinoma.

Frequency of high-grade prostatic intraepithelial neoplasia in Mexican population.

BACKGROUND: High-grade intraepithelial neoplasia (HGPIN) is the only lesion regarded as precursor of prostatic carcinoma, though its frequency is unknown in many countries. Here we studied the frequency of HGPIN in a population with high grade frequency of prostatic carcinoma. MATERIAL AND METHODS: A total of 486 cases of sextant prostatic biopsies performed from January 2001 to January 2006 were reviewed. These included 280 biopsies from patients belonging to an urban population, with medium or high socioeconomic status, from two hospitals in Mexico City. For comparison, 206 cases from the Regional Hospital of Tabasco located in the tropical zone of the country were included. This hospital receives patients from a rural population with low income and socioeconomic status. RESULTS: Of the total 486 cases, 162 (33.33%) cases were diagnosed as prostatic carcinoma and 319 (65.64%) as benign conditions. Only in five (1.03%) biopsies was HGPIN found. Three of these patients were from Mexico City, and two from the Regional Hospital of Tabasco. CONCLUSIONS: Even when our results were obtained only in three hospitals, they suggest that a low frequency of HGPIN on needle prostate biopsies does not necessarily mean a low frequency of prostatic carcinoma in the same population. The reason for such a disparity could be related to a reduced extension of HGPIN areas in the prostate gland. In populations with low frequency of HGPIN and high incidence of prostatic carcinoma, perhaps more biopsy cores should be obtained in order to minimize false negative results for premalignant lesions or early adenocarcinoma.

[Histological findings in 100 needle prostatic biopsies and original diagnosis of benignity]. / Hallazgos patológicos en 100 biopsias prostáticas por punción y diagnóstico original de benignidad.

INTRODUCTION: Detailed revision of prostate biopsies with benign alterations may show potentially malignant lesions limited to isolated fields, which may be overviewed in routine analysis. AIM: To exam the morphological alterations in patients with suspicious of prostatic carcinoma and benign diagnosis in needle biopsies. MATERIALS AND METHODS: During 2000-2001, one hundred consecutive patients with first prostate biopsy diagnosed as benign were included. Biopsies were performed by sextants or modified sextants technique. Slides were reviewed by two observers with knowledge of original diagnosis and this was accepted or modified in accordance to the findings found during the review. RESULTS: Patients age ranged between 57 and 79 years old. Nine per cent of biopsies originally diagnosed as benign revealed different potentially malignant lesions, which should be noted due to possible association with carcinoma. In this group, there were five biopsies with atypical small acinar proliferation, three with few isolated glands with xanthomatous cytoplasm, and one with scarce atypical cells in the prostatic stroma. In contrast with Caucasian and Afro-American population, frequency of high grade intraepithelial neoplasia in needle biopsy seems to be very low and this lesion was not found in any of the 100 biopsies reviewed. Some lesions that simulate carcinoma, as atypical basal cell hyperplasia, post-atrophic hyperplasia, and adenosis were diagnosed as benign, and there was none false positive result. CONCLUSIONS: A small but significant group of the biopsies originally diagnosed as benign lesions, showed atypical lesions in isolated fields that were overlooked in the routine analysis. It is necessary the urologist to ask for a directed review of the biopsies if clinical and laboratory data strongly suggest prostatic carcinoma. Additional histological cuts, immunohistochemical studies and more than one observer may increase the frequency of detection of potentially malignant lesions.

Hallazgos patológicos en 100 biopsias prostáticas por punción y diagnóstico original de benignidad / Histological findings in 100 NEEDLE prostatic biopsies and original diagnosis of benignity

Introduction. Detailed revision of prostate biopsies with benign alterations may show potentially malignant lesions limited to isolated fields, which may be overviewed in routine analysis. Aim. To exam the morphological alterations in patients with suspicious of prostatic carcinoma and benign diagnosis in needle biopsies. Materials and methods. During 2000-2001, one hundred consecutive patients with first prostate biopsy diagnosed as benign were included. Biopsies were performed by sextants or modified sextants technique. Slides were reviewed by two observers with knowledge of original diagnosis and this was accepted or modified in accordance to the findings found during the review. Results. Patients age ranged between 57 and 79 years old. Nine per cent of biopsies originally diagnosed as benign revealed different potentially malignant lesions, which should be noted due to possible association with carcinoma. In this group, there were five biopsies with atypical small acinar proliferation, three with few isolated glands with xanthomatous cytoplasm, and one with scarce atypical cells in the prostatic stroma. In contrast with Caucasian and Afro-American population, frequency of high grade intraepithelial neoplasia in needle biopsy seems to be very low and this lesion was not found in any of the 100 biopsies reviewed. Some lesions that simulate carcinoma, as atypical basal cell hyperplasia, post-atrophic hyperplasia, and adenosis were diagnosed as benign, and there was none false positive result. Conclusions. A small but significant group of the biopsies originally diagnosed as benign lesions, showed atypical lesions in isolated fields that were overlooked in the routine analysis. It is necessary the urologist to ask for a directed review of the biopsies if clinical and laboratory data strongly suggest prostatic carcinoma. Additional histological cuts, immunohistochemical studies and more than one observer may increase the frequency of detection of potentially malignant lesions.

Introducción. La revisión detallada de las biopsias prostáticas consideradas benignas, en ocasiones puede mostrar cambios histológicos con potencial maligno limitadas a campos aislados, que pueden ser pasadas por alto en la interpretación rutinaria. Objetivo. Examinar las alteraciones morfológicas en pacientes con sospecha de carcinoma prostático con diagnóstico de benignidad en biopsias prostáticas por punción. Material y métodos. En el periodo 2000-2001 se incluyeron 100 pacientes consecutivos cuya primera biopsia se interpretó como benigna. Las biopsias fueron por sextantes, o sextantes modificadas. Se revisaron las laminillas por dos observadores con el conocimiento del diagnóstico original y éste se aceptó o modificó de acuerdo con los hallazgos encontrados. Resultados. La edad varió de 57 a 79 años. Nueve de las 100 biopsias diagnosticadas como benignas revelaron alteraciones histológicas potencialmente malignas que debieron anotarse en el reporte de patología por su posible asociación con carcinoma. Éstas incluyeron cinco biopsias con proliferaciones acinares atípicas, tres con glándulas de aspecto xantomatoso en campos aislados y una con escasas células atípicas en el estroma prostático. En contraste con la población caucásica y afroamericana, la frecuencia de neoplasia intraepitelial prostática en biopsias por punción en nuestra población parece ser muy baja y ninguna de las 100 biopsias mostró esta alteración. Algunas lesiones que simulan carcinoma como la hiperplasia atípica de células básales, la hiperplasia postatrófica y la adenosis fueron reconocidas como benignas, y no hubo ningún resultado falso positivo. Conclusiones. Un porcentaje significativo de las biopsias con el diagnóstico original de patología benigna, mostraron en la revisión dirigida lesiones focales que fueron pasadas por alto en la práctica cotidiana, incluidas algunas con potencial maligno. El urólogo debe solicitar una revisión dirigida en búsqueda de lesiones sugestivas de malignidad si los datos clínicos y de laboratorio sugieren fuertemente la posibilidad de carcinoma. En estos casos, los niveles histológicos adicionales, los estudios inmunohistoquímicos y la revisión por más de un observador podrían incrementar la detección de lesiones potencialmente malignas.

Atypical regenerative hyperplasia of the esophagus in endoscopic biopsy: a mimicker of squamous esophagic carcinoma.

CONTEXT: Atypical regeneration can mimic carcinoma in various epithelia. On endoscopic biopsies, atypical regenerative hyperplasia of the esophagus may show pleomorphism and atypia, simulating esophageal squamous cell carcinoma. OBJECTIVE: To establish the most useful histologic features to distinguish atypical regenerative hyperplasia from esophageal carcinoma in endoscopic biopsies. DESIGN: To study the frequency and histologic appearance of atypical regenerative hyperplasia, which simulate carcinoma, we reviewed 600 endoscopic biopsies (555 with chronic esophagitis and 45 with carcinomas of the esophagus). We selected those cases in which the differential diagnosis included regenerative atypical hyperplasia versus esophageal carcinoma and cases of atypical regenerative hyperplasia that were mistaken for carcinoma. For comparative purposes, we studied 10 cases of esophageal carcinoma from endoscopic biopsies that were confirmed by esophagectomy. RESULTS: Among the cases with chronic esophagitis, we found 10 biopsies (1.8%) in which atypical regenerative hyperplasia mimicked carcinoma. In 7 cases, there were 4 to 12 years of follow-up, and no patient developed esophageal neoplasm. The remaining 3 patients were submitted to esophagectomy. None of these patients had carcinoma or dysplasia in the esophageal resection (false-positive biopsies). The most useful architectural changes in squamous carcinoma included stromal infiltration by nests, cords, or thin prongs of neoplastic keratinocytes, palisading desmoplasia, and in situ carcinoma in the adjacent epithelium. Malignant keratinocytes showed variable degrees of differentiation with differently shaped and sized cells, squamous epithelial pearls, individual keratinization, and atypical mitosis. In contrast, biopsies with atypical hyperplasia showed detached nests or irregular fragments without stroma and were made up of immature and relatively monotonous medium or small keratinocytes that were intermixed with inflammatory cells. Individual keratinization was rare, and no squamous pearls were seen. Other features of atypical hyperplasia included granulated tissue with atypical endothelial cells, nonatypical mitosis, lymphoid hyperplasia, and the absence of dysplasia or carcinoma in situ. Two biopsies showed stromal pseudoinfiltration as a result of tangential sectioning and were characterized by thick, round prongs composed of keratinocytes that penetrated regions with granulation or the inflamed tissues of esophageal ulcers. CONCLUSIONS: Atypical esophageal regenerative hyperplasia may mimic carcinoma in a small percentage of esophageal biopsies. If the histologic changes are not sufficient to establish an accurate diagnosis, medical treatment and subsequent biopsies should be performed, particularly if there are no endoscopic or radiologic data to support the presence of a neoplasm.

Gastrointestinal stromal tumors: clinical and pathological analysis of 24 cases.

BACKGROUND: Gastrointestinal stromal tumors (GISTs) are mesenchymal neoplasms of the gastrointestinal tract. They are positive for the expression of c-Kit protein at immunohistochemistry and their clinical presentation is variable. We conducted a study to identify true GISTs with known pathological and immunohistochemical criteria from other tumors of the gastrointestinal tract. METHODS: The clinical records of patients with the diagnosis of schwannoma, leiomyoma, leiomyosarcoma and tumor of uncertain biological behavior of the gastrointestinal tract were identified and the slides of paraffin obtained for review by two experienced pathologists in the diagnosis of GISTs. The clinical presentation, treatment and outcomes were analyzed. RESULTS: Twenty four GISTs (11 low-risk and 13 high-risk) were identified from 76 cases reviewed. All the confirmed GISTs were positive at immunohistochemistry for c-Kit expression. The two predominant location of the tumors were the stomach and small intestine. The outcome was good for benign and completely resected tumors. CONCLUSIONS: True GISTs can be recognized from other tumors by histological analysis. Immunohistochemistry to identify c-Kit protein expression is useful to confirm the diagnosis. Physicians must consider GISTs in patients with a lesion of the gastrointestinal tract resembling a smooth muscle tumor or/and in association with chronic or acute bleeding.

Resection of an esophageal metastasis from a renal cell carcinoma.

Surgery for patients with isolated metastases from renal cell carcinoma has been shown to improve survival. Isolated esophageal metastases are very uncommon among patients with renal cell carcinoma and there are no reports addressing the outcome of their resection. A 60-year-old woman who had previous history of renal cell carcinoma was admitted to the hospital with progressive dysphagia. Esophagography and endoscopy showed an esophageal tumor and biopsies were consistent with adenocarcinoma. No other site with tumor was identified on CT-scan. Resected specimen showed metastasis from renal cell carcinoma and the patient survived for an 11-month period. Although resection of metastatic renal cell carcinoma has been shown to improve long-term survival, the presence of esophageal metastases can be considered an adverse prognostic factor.

Pseudohyperplastic prostatic adenocarcinoma in transurethral resections of the prostate.

Pseudohyperplastic prostatic adenocarcinoma is a recently described variety of adenocarcinoma that has been studied in core-needle biopsies and prostatectomy specimens. It is characterized by malignant glands that simulate benign hyperplastic glands with complex, medium to large-sized glands with papillary infoldings, luminal undulations, branching or cystic dilatations, and columnar cells with macronucleoli and nuclear enlargement. Our aim was to define frequency, tumor volume, and histologic features of pseudohyperplastic prostatic adenocarcinoma in transurethral resections of prostate. We studied 250 specimens from transurethral resections; 150 specimens were originally diagnosed as benign glandular hyperplasia, and 100 as conventional prostate adenocarcinomas. Of the 150 biopsies originally diagnosed as benign glandular hyperplasia, two (1.3%) had areas of pseudohyperplastic carcinoma. In both cases the neoplasm was limited to two chips and measured 3 and 4 mm in diameter, respectively. Both patients were asymptomatic 2 and 4 years after diagnosis. Of the 100 biopsies with adenocarcinoma, areas of pseudohyperplastic carcinoma were found in three cases. In the first two these areas were found in two fragments, and in the other case they were found in three chips, and measured 3, 4, and 6 mm, respectively. The clinical course in these cases was unfavorable, and two patients had metastasis. Main histologic findings included crowded glands (5/5), papillary projections (5/5), nuclear enlargement (5/5) macronucleoli (4/5) cystic glandular dilatation (4/5) straight luminal borders (4/5), pink amorphous secretions (4/5) nuclear hyperchromasia (3/5) and transition to small acinar pattern of adenocarcinoma (3/5). In conclusion, pseudohyperplastic prostate carcinoma is rare in transurethral resection specimens and is found in scarce chips. Frequency of false negative results in biopsies originally diagnosed as benign glandular hyperplasia was 1.3%. In biopsies diagnosed as carcinoma, this frequency was 3%. These patients had an adverse clinical course, apparently due to association with areas of conventional adenocarcinoma.