Diagnosing bone lesions: a practical non-pathology centric formulaic approach.

Bone lesions are perceived to be some of the most difficult lesions that pathologists encounter. The reasons for this are multiple and include lack of experience/familiarity, the need to rely heavily on non-pathology information and data, and the fact that many lesions are associated with either procedures or treatments with significant morbidity. However, in fact, the majority of bone lesions can be accurately assessed on the basis of data not directly related to traditional pathologic based assessment. In order to achieve this state, the pathologist must understand the consistent clinical parameters of most bone lesions, including their clinical presentation, the bone involved, particularly the anatomic site of the bone involved, and a fundamental, basic understanding of imaging studies, especially the plain radiograph. Once these principles are understood and mastered, the pathologist can easily diagnose most bone lesions, using traditional pathologic assessment to confirm the diagnosis.

Cartilage-forming tumors.

Cartilage-forming tumors as a group are the most common primary bone tumors; this is largely due to the common occurrence of asymptomatic benign lesions such as osteochondroma and enchondroma. The common feature of these tumors is the presence of chondrocytic cells and the formation of cartilaginous tumor matrix. Some of these tumors are true neoplasms while others are hamartomas or developmental abnormalities. The morphologic heterogeneity of these tumors may be explained by a common multipotent mesenchymal cell differentiating along the lines of fetal-adult cartilage maturation. Recently mutations in IDH1 and IDH2 have been detected in a variety of benign and malignant cartilaginous tumors.(1-4.)

Putative multifunctional signature of lung metastases in dedifferentiated chondrosarcoma.

Chondrosarcomas are among the most malignant skeletal tumors. Dedifferentiated chondrosarcoma is a highly aggressive subtype of chondrosarcoma, with lung metastases developing within a few months of diagnosis in 90% of patients. In this paper we performed comparative analyses of the transcriptomes of five individual metastatic lung lesions that were surgically resected from a patient with dedifferentiated chondrosarcoma. We document for the first time a high heterogeneity of gene expression profiles among the individual lung metastases. Moreover, we reveal a signature of "multifunctional" genes that are expressed in all metastatic lung lesions. Also, for the first time, we document the occurrence of massive macrophage infiltration in dedifferentiated chondrosarcoma lung metastases.

Tumour-specific amplitude-modulated radiofrequency electromagnetic fields induce differentiation of hepatocellular carcinoma via targeting Cav3.2 T-type voltage-gated calcium channels and Ca2+ influx.

BACKGROUND: Administration of amplitude modulated 27·12 MHz radiofrequency electromagnetic fields (AM RF EMF) by means of a spoon-shaped applicator placed on the patient's tongue is a newly approved treatment for advanced hepatocellular carcinoma (HCC). The mechanism of action of tumour-specific AM RF EMF is largely unknown. METHODS: Whole body and organ-specific human dosimetry analyses were performed. Mice carrying human HCC xenografts were exposed to AM RF EMF using a small animal AM RF EMF exposure system replicating human dosimetry and exposure time. We performed histological analysis of tumours following exposure to AM RF EMF. Using an agnostic genomic approach, we characterized the mechanism of action of AM RF EMF. FINDINGS: Intrabuccal administration results in systemic delivery of athermal AM RF EMF from head to toe at levels lower than those generated by cell phones held close to the body. Tumour shrinkage results from differentiation of HCC cells into quiescent cells with spindle morphology. AM RF EMF targeted antiproliferative effects and cancer stem cell inhibiting effects are mediated by Ca2+ influx through Cav3·2 T-type voltage-gated calcium channels (CACNA1H) resulting in increased intracellular calcium concentration within HCC cells only. INTERPRETATION: Intrabuccally-administered AM RF EMF is a systemic therapy that selectively block the growth of HCC cells. AM RF EMF pronounced inhibitory effects on cancer stem cells may explain the exceptionally long responses observed in several patients with advanced HCC. FUND: Research reported in this publication was supported by the National Cancer Institute's Cancer Centre Support Grant award number P30CA012197 issued to the Wake Forest Baptist Comprehensive Cancer Centre (BP) and by funds from the Charles L. Spurr Professorship Fund (BP). DWG is supported by R01 AA016852 and P50 AA026117.

Her-2/neu expression in salivary duct carcinoma: an immunohistochemical and chromogenic in situ hybridization study.

Salivary duct carcinoma (SDC) shares significant morphologic and immunophenotypic overlap with ductal carcinoma of the breast, including HER-2/neu expression. Previous studies have detected HER-2/neu at the protein level in SDCs; however, no study, to date, has assayed whether this expression is related to gene amplification detected by chromogenic in situ hybridization (CISH). Formalin-fixed, paraffin-embedded tissue sections from 12 previously diagnosed SDCs were evaluated by immunohistochemistry (IHC) and CISH for HER-2/neu status. Result concordance was seen in all 12 cases. A total of 4 SDCs were positive by IHC; all 4 cases showed amplification with CISH. The remaining 8 cases were negative by IHC and showed no gene amplification with CISH. SDCs in this study show HER-2/neu overexpression on both the protein and gene levels in approximately 30% of cases. These findings suggest a role may exist for Herceptin (trastuzumab) based therapy in some SDC patients.

Somatostatin receptor scintigraphy in surveillance of pediatric brain malignancies.

BACKGROUND: Somatostatin receptor scintigraphy (SRS) has been successfully used in imaging PBTs and, as a functional imaging modality, may be better able to differentiate tumor from scar/necrosis. This retrospective study evaluates the role of SRS in post-treatment surveillance of PBTs. PROCEDURE: Twenty children (age range: 7 months to 24 years, mean: 9 years) with known brain malignancies underwent serial SRS and MRI. The sensitivity and specificity of SRS and MRI were compared for surveillance scanning using patient outcome as the reference standard. Somatostatin receptors (sstrs) expression was determined by immunohistochemistry (IHC) of available tumor specimens. RESULTS: SRS was true positive (TP) in 15 of 16 patients with proven disease found post-resection (n = 5) or during follow-up (n = 11). In contrast, MRI was positive in 12 of these 16 patients and equivocal in another two patients where it could not distinguish between radiation necrosis and tumor recurrence. The two patients with false negative (FN) MRI and proven disease were positive by SRS. SRS was negative in all four patients with no evidence of disease by follow-up (mean follow-up = 58 months). The only patient with a FN SRS (TP by MRI) was one without IHC evidence of sstrs. SRS was TP in 7/7 tumors with IHC documented sstrs. CONCLUSIONS: SRS is a useful adjunct to MRI for post-treatment surveillance of sstr-positive PBTs, particularly when MRI is equivocal.

Differentiating Intrarenal Ectopic Adrenal Tissue From Renal Cell Carcinoma in the Kidney.

BACKGROUND: Adrenal rest (AR) is the presence of ectopic adrenal cortical tissue, often identified incidentally during autopsy (20% of postmortem examination). In the kidney, AR can be found in 6% of the general population. Ectopic adrenal tissue is of no functional significance but may in some cases, pose a diagnostic challenge for the pathologist, especially in the context of renal clear cell renal cell carcinoma (RCC) and small needle biopsies. AIM: To investigate the utility of immunohistochemical stains in distinguishing AR from RCC. METHODS: Archival cases of AR, in our institution, were reviewed and compared with a cohort of RCC cases using a panel of immunohistochemical stains, including PAX2, PAX8, calretinin, and inhibin. RESULTS: Nine of 10 (90%) cases of AR showed positive staining for inhibin and negative staining for calretinin, PAX2 and PAX8. One AR case was positive for PAX2 and PAX8 in addition to inhibin. All (100%) RCC cases were positive for PAX2 and PAX8, but negative for inhibin and calretinin. CONCLUSIONS: A panel of PAX2, PAX8 and inhibin may be useful markers for distinguishing AR from RCC. Calretinin was noncontributory in our study.

Chondroblastoma of the femoral diaphysis: report of a rare phenomenon and review of literature.

Chondroblastoma (CB) is a relatively rare yet well-studied benign neoplasm of bone. The purported neoplastic cell is the chondroblast, a cell which normally populates areas of secondary ossification. Numerous studies have shown that CB overwhelmingly arises from the epimetaphyseal region of skeletally immature individuals. Only rare cases have been reported in the diaphyseal region, and many of these involve metacarpals or metatarsals, which may lack a true anatomic diaphysis. The remaining cases of diaphyseal CBs synchronously involve the neighboring epimetaphysis, making determination of the initiation point impossible. We report a case of a CB isolated to the radiologic femoral diaphysis. To our knowledge, this is the first case of a diaphyseal-based CB to be reported in the pathology literature and only the second case published overall.

Circulating mutational portrait of cancer: manifestation of aggressive clonal events in both early and late stages.

BACKGROUND: Solid tumors residing in tissues and organs leave footprints in circulation through circulating tumor cells (CTCs) and circulating tumor DNAs (ctDNA). Characterization of the ctDNA portraits and comparison with tumor DNA mutational portraits may reveal clinically actionable information on solid tumors that is traditionally achieved through more invasive approaches. METHODS: We isolated ctDNAs from plasma of patients of 103 lung cancer and 74 other solid tumors of different tissue origins. Deep sequencing using the Guardant360 test was performed to identify mutations in 73 clinically actionable genes, and the results were associated with clinical characteristics of the patient. The mutation profiles of 37 lung cancer cases with paired ctDNA and tumor genomic DNA sequencing were used to evaluate clonal representation of tumor in circulation. Five lung cancer cases with longitudinal ctDNA sampling were monitored for cancer progression or response to treatments. RESULTS: Mutations in TP53, EGFR, and KRAS genes are most prevalent in our cohort. Mutation rates of ctDNA are similar in early (I and II) and late stage (III and IV) cancers. Mutation in DNA repair genes BRCA1, BRCA2, and ATM are found in 18.1% (32/177) of cases. Patients with higher mutation rates had significantly higher mortality rates. Lung cancer of never smokers exhibited significantly higher ctDNA mutation rates as well as higher EGFR and ERBB2 mutations than ever smokers. Comparative analysis of ctDNA and tumor DNA mutation data from the same patients showed that key driver mutations could be detected in plasma even when they were present at a minor clonal population in the tumor. Mutations of key genes found in the tumor tissue could remain in circulation even after frontline radiotherapy and chemotherapy suggesting these mutations represented resistance mechanisms. Longitudinal sampling of five lung cancer cases showed distinct changes in ctDNA mutation portraits that are consistent with cancer progression or response to EGFR drug treatment. CONCLUSIONS: This study demonstrates that ctDNA mutation rates in the key tumor-associated genes are clinical parameters relevant to smoking status and mortality. Mutations in ctDNA may serve as an early detection tool for cancer. This study quantitatively confirms the hypothesis that ctDNAs in circulation is the result of dissemination of aggressive tumor clones and survival of resistant clones. This study supports the use of ctDNA profiling as a less-invasive approach to monitor cancer progression and selection of appropriate drugs during cancer evolution.

Mutational Landscapes of Smoking-Related Cancers in Caucasians and African Americans: Precision Oncology Perspectives at Wake Forest Baptist Comprehensive Cancer Center.

Background: Cancers related to tobacco use and African-American ancestry are under-characterized by genomics. This gap in precision oncology research represents a major challenge in the health disparities in the United States. Methods: The Precision Oncology trial at the Wake Forest Baptist Comprehensive Cancer Center enrolled 431 cancer patients from March 2015 to May 2016. The composition of these patients consists of a high representation of tobacco-related cancers (e.g., lung, colorectal, and bladder) and African-American ancestry (13.5%). Tumors were sequenced to identify mutations to gain insight into genetic alterations associated with smoking and/or African-American ancestry. Results: Tobacco-related cancers exhibit a high mutational load. These tumors are characterized by high-frequency mutations in TP53, DNA damage repair genes (BRCA2 and ATM), and chromatin remodeling genes (the lysine methyltransferases KMT2D or MLL2, and KMT2C or MLL3). These tobacco-related cancers also exhibit augmented tumor heterogeneities. Smoking related genetic mutations were validated by The Cancer Genome Atlas dataset that includes 2,821 cases with known smoking status. The Wake Forest and The Cancer Genome Atlas cohorts (431 and 7,991 cases, respectively) revealed a significantly increased mutation rate in the TP53 gene in the African-American subgroup studied. Both cohorts also revealed 5 genes (e.g. CDK8) significantly amplified in the African-American population. Conclusions: These results provide strong evidence that tobacco is a major cause of genomic instability and heterogeneity in cancer. TP53 mutations and key oncogene amplifications emerge as key factors contributing to cancer outcome disparities among different racial/ethnic groups.

Inactivation of BRCA1 and BRCA2 in ovarian cancer.

BACKGROUND: Although BRCA1 and BRCA2 play important roles in hereditary ovarian cancers, the extent of their role in sporadic ovarian cancers and their mechanisms of inactivation are not yet well understood. Our goal was to characterize BRCA2 mutations and mRNA expression in a group of ovarian tumors previously evaluated for BRCA1 mutations and mRNA expression. METHODS: The tumors of 92 unrelated women with "ovarian" cancer (i.e., ovarian, peritoneal, or fallopian tube cancer) were screened for BRCA2 null mutations using a protein truncation test. Methylation-specific polymerase chain reaction (PCR) was used to examine the BRCA2 promoter for hypermethylation in tumors that did not express BRCA2 mRNA. All statistical tests were two-sided. RESULTS: Nine tumors had a germline (n = 5) or somatic (n = 4) BRCA2 mutation; each was associated with loss of heterozygosity. All of the somatic (1445delC, E880X, 4286del8, and 5783delT) and one of the germline (5984ins4) mutations were unique to this study. One tumor had somatic mutations in both BRCA1 and BRCA2. Two tumors are, to our knowledge, the first cases of germline BRCA2-associated peritoneal cancer. Twelve additional tumors lacked detectable BRCA2 mRNA, but the BRCA2 promoter was hypermethylated in only one of them, suggesting that other mechanisms effect transcriptional silencing of BRCA2. Tumors lacking BRCA1 mRNA were more likely to lack BRCA2 mRNA than tumors expressing BRCA1 mRNA (P<.001). Overall, 82% (95% confidence interval [CI] = 74% to 90%) of the tumors contained alterations in BRCA1, BRCA2, or both genes. Of 41 informative tumors with some alteration in BRCA2, 36 also had an alteration in BRCA1. The frequency, but not the mechanism, of BRCA1 or BRCA2 dysfunction in ovarian cancer was independent of family history. CONCLUSIONS: Multiple mechanisms cause nearly universal dysfunction of BRCA1 and/or BRCA2 in hereditary and sporadic ovarian carcinoma. Ovarian cancers with BRCA2 dysfunction often have simultaneous BRCA1 dysfunction.

Ethanol as a local adjuvant for giant cell tumor of bone.

Giant cell tumor is an aggressive benign neoplasm of bone. A number of adjuvant agents have been used to supplement intralesional curettage to reduce the otherwise high local recurrence rate. High concentration ethanol is more readily available and less toxic to use than some common alternatives. No report on its use in a group of patients with giant cell tumor is available. Records were retrospectively reviewed for all giant cell tumors treated by intralesional curettage and high concentration ethanol irrigation as the only chemical adjuvant. Twenty-five primary excisional curettages and 12 repeat curettages for giant cell tumors of bone were performed in 31 patients. Patients were followed for a mean of three years and 10 months. There were five recurrences after primary excision procedures, and three after repeat excisions. Only use of a high-speed burr and lower Campanacci staging correlated with reduced recurrence rate, and these were not statistically significant. Most defects were filled with allograft or calcium sulfate. In the 11 patients treated primarily with curettage using a high-speed burr and adjuvant ethanol with minimum two-year follow-up, only one stage 3 lesion in a distal radius recurred. Multiple washes with high concentration ethanol, when used in conjunction with aggressive curettage including high-speed burring, is an effective and safe adjuvant. The necessity of any chemical adjuvant after appropriately aggressive curettage and burring can only be definitively demonstrated with a prospective, randomized, multi-center trial. Until such evidence becomes available, the use of adjuvant ethanol offers a compromise between higher toxicity adjuvants and no chemical adjuvant at all.

p21 expression predicts outcome in p53-null ovarian carcinoma.

PURPOSE: p21 is a direct p53 response gene. Although several studies have correlated p21 and p53 expression, only one has evaluated p21 expression as a function of sequenced p53 gene mutation. We hypothesize that such an analysis may be useful in prognosticating outcome for individuals diagnosed with epithelial ovarian cancer. EXPERIMENTAL DESIGN: DNA from the primary ovarian cancers of 267 patients was studied. p53 mutations were directly sequenced. Two percent or greater nuclear staining with WAF1/CIP1 monoclonal antibody was determined by a hazard ratio analysis to constitute positive p21 expression. RESULTS: Positive p21 nuclear staining occurred more frequently in p53 wild-type ovarian tumors than tumors found to have a p53 mutation (P = 0.001). Positive p21 staining conferred an overall survival advantage (P = 0.02). p21 expression in cancers with p53 missense mutations was not prognostic but did show a strong trend toward significance in the wild-type p53 subset (P = 0.056). Surprisingly, positive p21 staining reflected compromised survival for individuals with p53-null ovarian cancers (P = 0.005). The mean expression level for p21-positive stains in the wild-type group was greater than in null p53 cancers (23 versus 11%; P = 0.001). A Cox multivariable analysis revealed p21 to be a strong independent prognostic factor in p53-null ovarian cancer (P = 0.02). CONCLUSION: p21 expression is closely related to sequenced p53 mutations. This is the first study of positive p21 staining as an independent poor prognostic factor in p53-null ovarian cancer. A dual role for p21 activity, dependent on levels of expression, appears to explain these paradoxical results and is consistent with a complex model for regulation of p21.

The impact of p53 protein core domain structural alteration on ovarian cancer survival.

PURPOSE: Although survival with a p53 missense mutation is highly variable, p53-null mutation is an independent adverse prognostic factor for advanced stage ovarian cancer. By evaluating ovarian cancer survival based upon a structure function analysis of the p53 protein, we tested the hypothesis that not all missense mutations are equivalent. EXPERIMENTAL DESIGN: The p53 gene was sequenced from 267 consecutive ovarian cancers. The effect of individual missense mutations on p53 structure was analyzed using the International Agency for Research on Cancer p53 Mutational Database, which specifies the effects of p53 mutations on p53 core domain structure. Mutations in the p53 core domain were classified as either explained or not explained in structural or functional terms by their predicted effects on protein folding, protein-DNA contacts, or mutation in highly conserved residues. Null mutations were classified by their mechanism of origin. RESULTS: Mutations were sequenced from 125 tumors. Effects of 62 of the 82 missense mutations (76%) could be explained by alterations in the p53 protein. Twenty-three (28%) of the explained mutations occurred in highly conserved regions of the p53 core protein. Twenty-two nonsense point mutations and 21 frameshift null mutations were sequenced. Survival was independent of missense mutation type and mechanism of null mutation. CONCLUSIONS: The hypothesis that not all missense mutations are equivalent is, therefore, rejected. Furthermore, p53 core domain structural alteration secondary to missense point mutation is not functionally equivalent to a p53-null mutation. The poor prognosis associated with p53-null mutation is independent of the mutation mechanism.

Secondary chondrosarcoma of the pelvis arising from a solitary exostosis in an 11-year-old patient: a case report with 5-year follow-up.

Although conversion of an osteochondroma to chondrosarcoma is a well-described rare occurrence, it is usually associated with syndromes such as multiple hereditary exostoses and is much more common after maturity. We present here a rare case of secondary pelvic chondrosarcoma arising from a solitary exostosis in a pediatric patient. An 11-year-old, otherwise healthy, female was referred to our clinic for evaluation of a pelvic mass detected on a radiograph. The radiographs obtained by the referring physician demonstrated a large lesion arising from the right superior pubic ramus, which was visible but not identified on an abdominal radiograph several years prior. Histopathologic analysis showed chondrosarcoma which was supported by an additional opinion to rule out chondroblastic osteosarcoma. The patient was treated with wide resection without adjuvant therapy and is doing well with no evidence of recurrence five years post-operatively. There have been only a few small case series describing chondrosarcoma in the pediatric patient. Even rarer are descriptions of secondary chondrosarcoma with only occasional cases reported as part of larger case series. Chondrosarcoma is a rare and difficult diagnosis in the pediatric patient. There is often considerable debate between chondrosarcoma and chondroblastic osteosarcoma, and the treatment implications of differentiating these diagnoses are of paramount importance.

Consensus statement on effective communication of urgent diagnoses and significant, unexpected diagnoses in surgical pathology and cytopathology from the College of American Pathologists and Association of Directors of Anatomic and Surgical Pathology.

CONTEXT: Recognizing the difficulty in applying the concept of critical values to anatomic pathology diagnoses, the College of American Pathologists and the Association of Directors of Anatomic and Surgical Pathology have chosen to reevaluate the concept of critical diagnoses. OBJECTIVE: To promote effective communication of urgent and significant, unexpected diagnoses in surgical pathology and cytology. DESIGN: A comprehensive literature search was conducted and reviewed by an expert panel. RESULTS: A policy of effective communication of important results in surgical pathology and cytology is desirable to enhance patient safety and to address multiple regulatory requirements. CONCLUSIONS: Each institution should create its own policy regarding urgent diagnoses and significant, unexpected diagnoses in anatomic pathology. This policy should be separate from critical results or panic-value policies in clinical pathology, with the expectation of a different time frame for communication. Urgent diagnosis is defined as a medical condition that, in most cases, should be addressed as soon as possible. Significant, unexpected diagnosis is defined as a medical condition that is clinically unusual or unforeseen and should be addressed at some point in the patient's course. Further details of this statement are provided.

Relationship between HER-2 overexpression and brain metastasis in esophageal cancer patients.

AIM: To study if HER-2 overexpression by locally advanced esophageal cancers increase the chance of brain metastasis following esophagectomy. METHODS: We retrospectively reviewed the medical records of esophageal cancer patients who underwent esophagectomy at University of Iowa Hospitals and Clinics between 2000 and 2010. Data analyzed consisted of demographic and clinical variables. The brain metastasis tissue was assayed for HER-2 overexpression utilizing the FDA approved DAKO Hercept Test(®). RESULTS: One hundred and forty two patients were reviewed. Median age was 64 years (36-86 years). Eighty eight patients (62%) received neoadjuvant chemoradiotherapy. Pathological complete and partial responses were achieved in 17 (19%) and 71 (81%) patients. Cancer relapsed in 43/142 (30%) patients. The brain was the first site of relapse in 9/43 patients (21%, 95% CI: 10%-36%). HER-2 immunohistochemistry testing of the brain metastasis tissue showed that 5/9 (56%) cases overexpressed HER-2 (3+ staining). CONCLUSION: HER-2 overexpression might be associated with increased risk of brain metastasis in esophageal cancer patients following esophagectomy. Further studies will be required to validate this observation.