Fredrik Petersson

Summary

Country: Sweden

Publications

  1. ncbi request reprint Atypical cellular unguioblastic fibroma-A rare case with more atypical histological features than previously reported
    Fredrik Petersson
    Department of Pathology, National University Health System, Singapore
    Am J Dermatopathol 32:387-91. 2010
  2. ncbi request reprint Cystic lymphoid hyperplasia of the parotid gland as the initial manifestation of HIV infection
    Bingcheng Wu
    Department of Pathology, National University Health System, 5 Lower Kent Ridge Road, Singapore 119074
    Singapore Med J 55:e12-6. 2014
  3. pmc Sclerosing polycystic adenosis of salivary glands: a review with some emphasis on intraductal epithelial proliferations
    Fredrik Petersson
    Department of Pathology, National University Health System, 5 Lower Kent Ridge Road, Singapore 119074, Singapore
    Head Neck Pathol 7:S97-106. 2013
  4. pmc Carcinosarcoma ex non-recurrent pleomorphic adenoma composed of TTF-1 positive large cell neuroendocrine carcinoma and myofibrosarcoma: apropos a rare Case
    Fredrik Petersson
    Department of Pathology, National University Health System, 5 Lower Kent Ridge Road, Singapore, 119074, Singapore
    Head Neck Pathol 7:163-70. 2013
  5. doi request reprint Epstein-Barr virus-associated smooth muscle tumor-report of 3 tumors including 1 intracerebral case with a prominent intratumoral B-lymphocytic component and plasma cells
    Fredrik Petersson
    Department of Pathology, National University Health System, Singapore
    Ann Diagn Pathol 17:91-8. 2013
  6. pmc Metastasis of occult prostatic carcinoma to the sphenoid sinus: report of a rare case and a review of the literature
    Fredrik Petersson
    Department of Pathology, National University Health System, 5 Lower Kent Ridge Road, Singapore, 119074, Singapore
    Head Neck Pathol 6:258-63. 2012
  7. pmc Mammary analogue secretory carcinoma: the first submandibular case reported including findings on fine needle aspiration cytology
    Fredrik Petersson
    Department of Pathology, National University Health System, 5 Lower Kent Ridge Road, Singapore, 119074, Singapore
    Head Neck Pathol 6:135-9. 2012
  8. doi request reprint Spiradenocarcinoma with low-grade basal cell adenocarcinoma pattern: report of a case with varied morphology and wild type TP53
    Fredrik Petersson
    Department of Pathology, National University Health System, Singapore
    J Cutan Pathol 39:372-6. 2012
  9. pmc Review of juxtaglomerular cell tumor with focus on pathobiological aspect
    Naoto Kuroda
    Department of Diagnostic Pathology, Kochi Red Cross Hospital, Shin honmachi 2 13 51, Kochi City, Kochi 780 8562, Japan
    Diagn Pathol 6:80. 2011
  10. pmc Chromophobe renal cell carcinoma with liposarcomatous dedifferentiation - report of a unique case
    Fredrik Petersson
    Department of Pathology, National University Hospital System, Singapore 119074
    Int J Clin Exp Pathol 3:534-40. 2010

Detail Information

Publications50

  1. ncbi request reprint Atypical cellular unguioblastic fibroma-A rare case with more atypical histological features than previously reported
    Fredrik Petersson
    Department of Pathology, National University Health System, Singapore
    Am J Dermatopathol 32:387-91. 2010
    ..The proliferative index as measured immunohistochemically (Mib-1/Ki-67) was 5%. The extent of these atypical histological features has not previously been described. One-year follow-up has been uneventful...
  2. ncbi request reprint Cystic lymphoid hyperplasia of the parotid gland as the initial manifestation of HIV infection
    Bingcheng Wu
    Department of Pathology, National University Health System, 5 Lower Kent Ridge Road, Singapore 119074
    Singapore Med J 55:e12-6. 2014
    ....
  3. pmc Sclerosing polycystic adenosis of salivary glands: a review with some emphasis on intraductal epithelial proliferations
    Fredrik Petersson
    Department of Pathology, National University Health System, 5 Lower Kent Ridge Road, Singapore 119074, Singapore
    Head Neck Pathol 7:S97-106. 2013
    ..Using HUMARA methodology (non-random inactivation of X-chromosomes), six cases with atypical epithelial proliferations have been shown to be clonal processes. Recurrences have been reported in up to 19 % of cases...
  4. pmc Carcinosarcoma ex non-recurrent pleomorphic adenoma composed of TTF-1 positive large cell neuroendocrine carcinoma and myofibrosarcoma: apropos a rare Case
    Fredrik Petersson
    Department of Pathology, National University Health System, 5 Lower Kent Ridge Road, Singapore, 119074, Singapore
    Head Neck Pathol 7:163-70. 2013
    ..Strong immunohistochemical expression of p53 was documented in both the carcinomatous and sarcomatous components as well as in the atypical epithelial component in the transition zone associated with the hyalinized pleomorphic adenoma...
  5. doi request reprint Epstein-Barr virus-associated smooth muscle tumor-report of 3 tumors including 1 intracerebral case with a prominent intratumoral B-lymphocytic component and plasma cells
    Fredrik Petersson
    Department of Pathology, National University Health System, Singapore
    Ann Diagn Pathol 17:91-8. 2013
    ..The intracranial tumor was associated with prominent intracerebral edema and displayed, in addition to a prominent intratumoral T-cell component, a hitherto unreported component of prominent intratumoral B cells and plasma cells...
  6. pmc Metastasis of occult prostatic carcinoma to the sphenoid sinus: report of a rare case and a review of the literature
    Fredrik Petersson
    Department of Pathology, National University Health System, 5 Lower Kent Ridge Road, Singapore, 119074, Singapore
    Head Neck Pathol 6:258-63. 2012
    ..2). Subsequent urological examination confirmed a locally advanced prostatic carcinoma with significantly increased serum-PSA (4,561 μg/l) and bone scintigraphy showed widespread metastasis...
  7. pmc Mammary analogue secretory carcinoma: the first submandibular case reported including findings on fine needle aspiration cytology
    Fredrik Petersson
    Department of Pathology, National University Health System, 5 Lower Kent Ridge Road, Singapore, 119074, Singapore
    Head Neck Pathol 6:135-9. 2012
    ..Adjuvant radiotherapy was administered. No local recurrence or metastatic disease has been detected during a follow up period of 28 months...
  8. doi request reprint Spiradenocarcinoma with low-grade basal cell adenocarcinoma pattern: report of a case with varied morphology and wild type TP53
    Fredrik Petersson
    Department of Pathology, National University Health System, Singapore
    J Cutan Pathol 39:372-6. 2012
    ..Although the malignant component displayed patchy areas with nuclear p53 immunoreactivity with variable intensity, no mutation in the TP53 gene was identified...
  9. pmc Review of juxtaglomerular cell tumor with focus on pathobiological aspect
    Naoto Kuroda
    Department of Diagnostic Pathology, Kochi Red Cross Hospital, Shin honmachi 2 13 51, Kochi City, Kochi 780 8562, Japan
    Diagn Pathol 6:80. 2011
    ..Additionally, pathologists and urologists need to recognize that this neoplasm in most cases pursues a benign course, but aggressive forms may develop in some cases...
  10. pmc Chromophobe renal cell carcinoma with liposarcomatous dedifferentiation - report of a unique case
    Fredrik Petersson
    Department of Pathology, National University Hospital System, Singapore 119074
    Int J Clin Exp Pathol 3:534-40. 2010
    ..This is the first reported case of a sarcomatoid CRCC where the sarcomatous component displayed features of a pleomorphic liposarcoma. The patient died from widespread metastatic disease 12 months after nephrectomy...
  11. doi request reprint Low-grade ductal carcinoma in situ and invasive mammary carcinoma with columnar cell morphology arising in a complex fibroadenoma in continuity with columnar cell change and flat epithelial atypia
    Fredrik Petersson
    Department of Pathology, National University Health System, Singapore
    Int J Surg Pathol 18:352-7. 2010
    ..There were strong cytomorphological similarities between the invasive carcinoma and the low-grade ductal carcinoma in situ, which also showed significant overlap in the immunohistochemical findings...
  12. pmc Anaplastic myoepithelial carcinoma of the sinonasal tract: an underrecognized salivary-type tumor among the sinonasal small round blue cell malignancies? Report of one case and a review of the literature
    Fredrik Petersson
    Department of Pathology, National University Health System, 5 Lower Kent Ridge Road, Singapore
    Head Neck Pathol 5:144-53. 2011
    ..Mib-1/Ki-67 showed an average proliferation of 60-70%. Fluorescent in situ hybridization revealed no EWS-gene translocation. In situ hybridization for EBER was negative...
  13. doi request reprint Epstein-Barr virus--associated smooth muscle tumor mimicking cutaneous angioleiomyoma
    Fredrik Petersson
    Department of Pathology, National University Health System, Singapore
    Am J Dermatopathol 33:407-9. 2011
    ..This unique presentation emphasizes the importance of considering this pathologic entity when solitary smooth muscle tumors with the histological features of an angioleiomyoma are encountered in immunocompromised patients...
  14. pmc Sclerosing polycystic adenosis of the parotid gland: report of a bifocal, paucicystic variant with ductal carcinoma in situ and pronounced stromal distortion mimicking invasive carcinoma
    Fredrik Petersson
    Department of Pathology, National University Health System, 5 Lower Kent Ridge Road, Singapore
    Head Neck Pathol 5:188-92. 2011
    ..The proliferative activity (Mib-1/Ki-67) was low (1-2%) in the benign component whereas increased proliferation was seen in the DCIS and in the areas with pseudoinfiltration which also featured atypical mitoses...
  15. pmc Biphasic low-grade nasopharyngeal papillary adenocarcinoma with a prominent spindle cell component: report of a case localized to the posterior nasal septum
    Fredrik Petersson
    Department of Pathology, National University Health System, 5 Lower Kent Ridge Road, Singapore 119074, Singapore
    Head Neck Pathol 5:306-13. 2011
    ..The proliferative activity (Mib-1/Ki-67) was low; 3-4%. In the molecular genetic study we found no mutations at position 1799 (exon 15) in the BRAF-gene, (BRAFV600E) or in exons 9 and 11 of the KIT-gene...
  16. pmc Paucilymphoid non-keratinizing nasopharyngeal carcinoma with prominent stromal desmoplasia--an unusual case reported with brief comments on uncommon histological variants
    Fredrik Petersson
    Department of Pathology, National University Health System, Singapore
    Int J Clin Exp Pathol 4:410-5. 2011
    ..Awareness of the histological spectrum of NK-NPC is important in clinical practice and this is not always adequately highlighted in currently used standard textbooks of head and neck pathology...
  17. doi request reprint Pigmented Paget disease--a diagnostic pitfall mimicking melanoma
    Fredrik Petersson
    Department of Oncology Pathology, Karolinska Institute, Karolinska University Hospital, Stockholm, Sweden
    Am J Dermatopathol 31:223-6. 2009
    ..The latter are especially important in some extraordinary cases in which there may be an associated intraepithelial melanocytic hyperplasia...
  18. doi request reprint Dendritic cell neurofibroma sine pseudorosettes: report of a case with a granulomatous appearance
    Fredrik Petersson
    Department of Pathology, National University Hospital, Singapore
    Am J Dermatopathol 33:742-4. 2011
    ..Intralesional small neurites positive for neurofilament and perilesional perineural cells positive for epithelial membrane antigen were documented immunohistochemically...
  19. doi request reprint Multifocal matrix-producing mammary carcinoma mimicking lobular carcinoma on core biopsy - A case with long survival reported
    Fredrik Petersson
    Department of Pathology, National University Health System, 5 Lower Kent Ridge Road, Singapore 119074, Singapore
    Pathol Res Pract 206:527-31. 2010
    ..The proliferative activity was low (<5%) in areas both with and without matrix production. Despite significant tumor volume and high-grade histologic features, an 8-year follow-up has been uneventful...
  20. doi request reprint Characterization of the gastric cardia in volunteers from the general population. Type of mucosa, Helicobacter pylori infection, inflammation, mucosal proliferative activity, p53 and p21 expression, and relations to gastritis
    Fredrik Petersson
    Pathology Research Department, Ryhov Hospital, Jonkoping, Sweden
    Dig Dis Sci 55:46-53. 2010
    ..pylori infection. There are some differences regarding inflammation, proliferative activity, and p53 expression between the cardia and other regions of the stomach, yet the significance of these differences remains to be clarified...
  21. doi request reprint Immunohistochemical detection of lymphovascular invasion with D2-40 in melanoma correlates with sentinel lymph node status, metastasis and survival
    Fredrik Petersson
    Department of Oncology Pathology, Karolinska Institute, Karolinska University Hospital, Stockholm, Sweden
    J Cutan Pathol 36:1157-63. 2009
    ..4 (95% CI 1.2-16.8). For the first time, we herein show a positive correlation with LVI in melanoma detected with immunohistochemistry and distant metastasis, overall survival and disease-free survival...
  22. doi request reprint Eruptive syringoma of the penis. A report of 2 cases and a review of the literature
    Fredrik Petersson
    Department of Pathology, Karolinska Institute, Karolinska University Hospital, Stockholm, Sweden
    Am J Dermatopathol 31:436-8. 2009
    ..These are compared with all the previously published cases. Clinical and histopathological differential diagnoses are discussed, and a literature review is presented...
  23. doi request reprint Minute alveolar soft part sarcoma of the endocervix: the smallest ever published case
    Fredrik Petersson
    Department of Pathology, National University Health System, Singapore
    Appl Immunohistochem Mol Morphol 17:553-6. 2009
    ..Owing to the small number of published ASPSs in the cervix, the optimal treatment strategy has yet to be determined...
  24. doi request reprint Sclerosing sweat duct-like carcinoma of the tongue-a case report and a review of the literature
    Fredrik Petersson
    Department of Pathology, National University Health System, Singapore
    Am J Dermatopathol 31:691-4. 2009
    ..p63 was positive in the peripheral parts of the neoplastic ducts with negative reaction in the luminal cells...
  25. pmc Low-grade sarcoma in classical seminoma - the first case reported
    Fredrik Petersson
    Department of Pathology, National University Health System, Singapore 119074
    Int J Clin Exp Pathol 3:203-9. 2009
    ..No other germ cell tumor components were found. To the best of our knowledge, we herein present the first tumor of a pure classical seminoma with an associated low-grade sarcomatous component...
  26. doi request reprint Large cell calcifying Sertoli cell tumor: a clinicopathologic study of 1 malignant and 3 benign tumors using histomorphology, immunohistochemistry, ultrastructure, comparative genomic hybridization, and polymerase chain reaction analysis of the PRKAR1A ge
    Fredrik Petersson
    Department of Pathology, National University Health System, Singapore 119074, Singapore
    Hum Pathol 41:552-9. 2010
    ....
  27. doi request reprint Mucinous cystadenocarcinoma of the breast with amplification of the HER2-gene confirmed by FISH: The first case reported
    Fredrik Petersson
    Department of Pathology, National University Health System, Singapore 119074, Singapore
    Hum Pathol 41:910-3. 2010
    ....
  28. doi request reprint Renal cell carcinoma with areas mimicking renal angiomyoadenomatous tumor/clear cell papillary renal cell carcinoma
    Fredrik Petersson
    Department of Pathology, National University Health System, Singapore, Singapore
    Hum Pathol 44:1412-20. 2013
    ..Despite the combination of positivity for α-methylacyl-CoA racemase and cytokeratin 7 in 2 cases, there was nothing to suggest of the possibility of a conventional papillary renal cell carcinoma with a predominance of clear cells...
  29. doi request reprint A distinctive translocation carcinoma of the kidney; "rosette forming," t(6;11), HMB45-positive renal tumor: a histomorphologic, immunohistochemical, ultrastructural, and molecular genetic study of 4 cases
    Fredrik Petersson
    Department of Pathology, Charles University Hospital, 304 60 Plzen, Czech Republic
    Hum Pathol 43:726-36. 2012
    ..No von Hippel-Lindau tumor suppressor gene mutation, promotor methylation or loss of heterozygosity of 3p was found. Losses of part of chromosome 1 and chromosome 22 were found in one case...
  30. doi request reprint Thymoma with nuclear expression of thyroid transcription factor-1: a potential diagnostic pitfall on core biopsy
    Benedict Yan
    Department of Pathology, National University Hospital Systems, Singapore
    Appl Immunohistochem Mol Morphol 19:76-81. 2011
    ..No immunohistochemical evidence of neuroendocrine differentiation was identified with synaptophysin, chromogranin A, and CD56...
  31. ncbi request reprint Gastric epithelial proliferation and p53 and p21 expression in a general population sample: relations to age, sex, and mucosal changes associated with H. pylori infection
    Fredrik Petersson
    Pathology Research Department, Ryhov Hospital, Jonkoping, Sweden
    Dig Dis Sci 47:1558-66. 2002
    ..pylori infection. The action of p53 appears to be independent of p21 activity...
  32. ncbi request reprint Profiling and identification of eubacteria in the stomach of Mongolian gerbils with and without Helicobacter pylori infection
    Yi Qian Sun
    Department of Biomedicine and Surgery Faculty of Health Sciences, University of Linkoping, Jonkoping, Sweden
    Helicobacter 8:149-57. 2003
    ..The presence of an indigenous bacterial flora with suppressive effect on H. pylori may cause difficulties with establishing this experimental model...
  33. doi request reprint Sporadic hybrid oncocytic/chromophobe tumor of the kidney: a clinicopathologic, histomorphologic, immunohistochemical, ultrastructural, and molecular cytogenetic study of 14 cases
    Fredrik Petersson
    Department of Pathology, National University Hospital System, Singapore, Singapore
    Virchows Arch 456:355-65. 2010
    ..At worst, these tumors could have a low malignant potential, which only can be found out with longer follow-up...
  34. doi request reprint Renal small cell oncocytoma with pseudorosettes A histomorphologic, immunohistochemical, and molecular genetic study of 10 cases
    Fredrik Petersson
    Department of Pathology, Charles University and University Hospital, 304 60 Plzen, Czech Republic Department of Pathology, National University Health System, 119074 Singapore
    Hum Pathol 42:1751-60. 2011
    ..All tumors behaved in a benign fashion during follow-up (mean, 3.1 years; median, 1 year)...
  35. doi request reprint Bilateral renal tumors; conventional clear cell carcinoma and contralateral t(6;11)/t(X;17)-like tumor Histomorphologic, immunohistochemical, ultrastructural and molecular genetic studies including the report of a novel mutation in the VHL gene
    Fredrik Petersson
    Department of Pathology, National University Health System, Singapore
    Ann Diagn Pathol 15:362-9. 2011
    ..This tumor displayed a complex karyotype. A novel germ line mutation in the VHL gene (c.439A>G/p.I147V) was also identified in this patient...
  36. pmc Muco-submucosal elongated polyps of the gastrointestinal tract: a case series and a review of the literature
    Char Loo Tan
    Department of Pathology, National University Hospital System, Singapore 119074, Singapore
    World J Gastroenterol 19:1845-9. 2013
    ..The duodenal polyps displayed lipomatous metaplasia of the submucosal stroma. The dual vascular phenotype of the vascular component was confirmed by immunohistochemistry with D2-40 and CD31...
  37. doi request reprint Biphasic alveolosquamoid renal carcinoma: a histomorphological, immunohistochemical, molecular genetic, and ultrastructural study of a distinctive morphologic variant of renal cell carcinoma
    Fredrik Petersson
    Department of Pathology, Charles University in Prague Faculty of Medicine in Plzen, Plzen, Czech Republic
    Ann Diagn Pathol 16:459-69. 2012
    ..Multiple chromosomal aberrations were identified, some of them located in regions with known tumor suppressor genes and oncogenes...
  38. doi request reprint Quantitative assessment of the subepithelial collagen band does not increase the accuracy of diagnosis of collagenous colitis
    Carlos A Rubio
    Department of Pathology, Karolinska Institute and University Hospital, Stockholm, Sweden
    Am J Clin Pathol 130:375-81. 2008
    ..In agreement with Lazenby's statement: "Focusing solely on the collagen band can result in both over- and underdiagnosis"..
  39. doi request reprint Testicular germ cell tumor composed of placental site trophoblastic tumor and teratoma
    Fredrik Petersson
    Department of Pathology, National University Health System, Singapore
    Hum Pathol 41:1046-50. 2010
    ..The patient is alive and well 3 years after the orchiectomy without additional treatment...
  40. doi request reprint Nonexophytic nasopharyngeal carcinoma: high frequency of advanced lymph node and distant metastasis
    Kwok Seng Loh
    Department of Otolaryngology Head and Neck Surgery, National University Health System, National University of Singapore, Singapore
    Otolaryngol Head Neck Surg 145:594-8. 2011
    ..The authors aim to characterize the clinicopathological features and survival outcomes of nonexophytic NPC in a high-incidence area...
  41. pmc Epstein-barr virus-associated smooth muscle tumor of the larynx: report of a rare case mimicking leiomyosarcoma
    Jingxiang Huang
    Department of Pathology, National University Health System, 5 Lower Kent Ridge Road, Singapore 119074, Singapore
    Head Neck Pathol 4:300-4. 2010
    ..This case emphasizes the importance of considering this pathologic entity when solitary smooth muscle actin-expressing tumors are encountered in the larynx of immunocompromised patients...
  42. doi request reprint Lymphoepithelial carcinoma of the parotid gland arising in an intraglandular lymph node: report of a rare case mimicking metastasis
    Sarika Gupta
    Department of Pathology, National University Health System, Singapore, Singapore
    Ann Diagn Pathol 16:416-21. 2012
    ..This appearance of the tumor simulated a metastasis that was excluded by exhaustive radiologic and clinicopathologic investigations...
  43. pmc EBV-positive plasmacytoma of the submandibular gland--report of a rare case with molecular genetic characterization
    Benedict Yan
    Department of Pathology, National University Health System, 5 Lower Kent Ridge Road, Singapore 119074, Singapore
    Head Neck Pathol 5:389-94. 2011
    ..KRAS genetic analysis did not reveal any mutations of codons 12, 13 and 61...
  44. ncbi request reprint Further studies on serrated neoplasias of the cardia: a review and case report
    Carlos A Rubio
    Department of Pathology, Karolinska Institute and University Hospital, Stockholm, Sweden
    Anticancer Res 27:4431-4. 2007
    ..Serrated adenomas of the cardia seem to have a particular proclivity to evolve into invasive carcinomas...
  45. pmc Ectopic cervical thymoma: a report of two cases of a rare entity frequently misdiagnosed on fine needle aspiration cytology and frozen section
    Benedict Yan
    Department of Pathology, National University Health System, 5 Lower Kent Ridge Road, Singapore, 119074, Singapore
    Head Neck Pathol 4:152-6. 2010
    ..Short follow-up precludes conclusion on the implication of positive margins in conjunction with adjuvant radiotherapy for one of the patients presented herein...
  46. doi request reprint A comparative study of tissue ω-6 and ω-3 polyunsaturated fatty acids (PUFA) in benign and malignant pathologic stage pT2a radical prostatectomy specimens
    Martin C Schumacher
    Department of Molecular Medicine and Surgery, Karolinska Institutet Department of Urology, Stockholm, Sweden
    Urol Oncol 31:318-24. 2013
    ..To analyze different polyunsaturated fatty acid (PUFA) tissue levels in malignant compared with benign prostatic tissue from the same prostate specimens...
  47. doi request reprint Intra- and interobserver reproducibility of interpretation of immunohistochemical stains of prostate cancer
    Sara Jonmarker Jaraj
    Department of Oncology Pathology, Karolinska Institutet, Karolinska University Hospital Solna, 171 76, Stockholm, Sweden
    Virchows Arch 455:375-81. 2009
    ..Although educated pathologists were faster, the level of pathology training is not crucial for obtaining reproducible results in the analysis of TMA-based studies...
  48. doi request reprint Desmoplastic small round cell tumor of major salivary glands: report of 1 case and a review of the literature
    Brendan Pang
    Department of Pathology, National University of Singapore, Singapore
    Appl Immunohistochem Mol Morphol 19:70-5. 2011
    ..Desmoplastic small round cell tumor should be considered in the differential diagnosis of a salivary gland neoplasm with a basaloid or small cell pattern on fine-needle aspiration cytology...
  49. doi request reprint Intranuclear inclusions in epithelial cells of benign proliferative breast lesions
    Oi Harada
    Department of Pathology, Singapore General Hospital, Singapore
    J Clin Pathol 64:776-80. 2011
    ..To document and clarify the nature of intranuclear inclusions of luminal epithelium in benign proliferative breast lesions...
  50. pmc Intracerebral metaplastic meningioma with prominent ossification and extensive calcification
    Jingxiang Huang
    Department of Pathology, National University Health System, Singapore
    Rare Tumors 3:e20. 2011
    ..The tumor displayed a heretofore unpublished combination of extensive metaplastic bone formation and prominent non-psammomatous calcifications with focal chicken-wire pattern...