Cell Cycle Checkpoints p16 and p21-Strong Predictors of Clinicopathologic Outcomes in High-Grade Osteosarcoma.

PURPOSE: In this study, we used a series of immunohistochemical measurements of 2 cell cycle regulators, p16 and p21, to evaluate their prognostic value, separately and in combination, for the disease outcomes. METHOD: A total of 101 patients with high-grade osteosarcoma were included in this study. Clinicopathologic data were collected, and immunohistochemistry for p16 and p21 was performed and interpreted by 3 independent pathologists. Statistical analysis was performed to assess the strength of each of these markers relative to disease outcome. RESULTS: Our results indicate that more than 90% expression (high) of p16 by immunohistochemistry on the initial biopsy has a strong predictive value for good histologic response to chemotherapy. The patients are also more likely to survive the past 5 years and less likely to develop metastasis than patients with less than 90% p16 (low) expression. The results for p21, on the other hand, show a unique pattern of relationship to the clinicopathologic outcomes of the disease. Patients with less than 1% (low) or more than 50% (high) expression of p21 by immunohistochemistry show a higher chance of metastasis, poor necrotic response to chemotherapy, and an overall decreased survival rate when compared with p21 expression between 1% and 50% (moderate). Our results also showed that the expression of p16 and combined p16 and p21 demonstrates a stronger predictive relationship to 5-year survival than tumor histologic necrosis and p21 alone. DISCUSSION: The results of this study, once proven to be reproducible by a larger number of patients, will be valuable in the initial assessment and risk stratification of the patients for treatment and possibly the clinical trials.

Calcified chondroid mesenchymal neoplasm: report of a case involving the temporomandibular joint region and review of the literature.

The calcified chondroid mesenchymal neoplasm (CCMN) represents a recently recognized tumor type with only 50 well-documented cases in the English-language literature. Herein we report an additional case of CCMN presenting as a large mass in the temporomandibular joint region of a 41-year-old female. A review of previously reported cases and the current case of CCMN shows the following features: 1) average age 52 years (range 14-87 years) and an approximately even sex distribution; 2) most frequently involved sites: distal extremities (including foot, hand, wrist, forearm) (n=41) and temporomandibular joint/temporal/parotid region (n=9); 3) multilobular soft tissue tumor with chondroid to cartilaginous matrix, often grungy or lace-like calcifications, and variable cytologic atypia; 4) frequently detected FN1 rearrangement (n=15), including FN1 fusion with FGFR2 (n=7) or other receptor tyrosine kinases; 5) 2 reported local recurrences (after incomplete excision); 6) no reports of malignant biologic behavior.

Histones and their practical application in bone tumors: Do I always need them?

Historically, the diagnosis of giant cell-rich neoplasms arising in bone has been challenging owing to overlapping clinical and radiographic findings resulting in the difficult separation of several neoplasms, particularly when biopsy material is limited. However, with the discovery of the driver histone mutations in giant cell tumor of bone (GCTB) and chondroblastoma, as well as USP6 rearrangements in aneurysmal bone cyst, pathologists now have objective ancillary tools to aid in the separation of several histologically similar giant cell-rich neoplasms. Furthermore, the recognition of histone mutations has allowed pathologists to revisit several entities, such as "malignant chondroblastoma," and furthered our understanding of phenomena such as "aneurysmal bone cyst-like change," formerly recognized as "secondary aneurysmal bone cyst." Herein, the evolution of testing for histone mutations in bone tumors is considered; the sensitivity and specificity of the histone antibodies is reviewed; and a practical guide for the use of these ancillary tests is offered.

Accuracy of Time to Treatment Initiation Data in Musculoskeletal Soft Tissue Sarcoma.

Background: Time to treatment initiation (TTI) is a quality metric in cancer care. The purpose of this study is to determine the accuracy of TTI data from a single cancer center registry that reports to the National Cancer Database (NCDB) for sarcoma diagnoses. Methods: A retrospective analysis of a single Commission on Cancer (CoC)-accredited cancer center's tumor registry between 2006 and 2016 identified 402 patients who underwent treatment of a musculoskeletal soft tissue sarcoma and had TTI data available. Registry-reported TTI was extracted from the tumor registry. Effective TTI was manually calculated by medical record review as the number of days from the date of tissue diagnosis to initiation of first effective treatment. Effective treatment was defined as oncologic surgical excision or initiation of radiation therapy or chemotherapy. Registry-reported TTI and effective TTI values were compared for concordance in all patients. Results: In the entire cohort, 25% (99/402) of patients had TTI data discordance, all related to surgical treatment definition. For patients with a registry-reported value of TTI = 0 days, 74% (87/118) had a diagnostic surgical procedure coded as their first treatment event, with 73 unplanned incomplete excision procedures and 14 incisional biopsies. In these patients, effective TTI was on average 59 days (P < 0.001). For patients with a registry-reported value of TTI >0 days, only 4% (12/284) had discordant TTI values. Conclusions: Nearly three-fourths of patients with a registry-reported value of TTI = 0 days in a large, CoC-accredited cancer center registry had a diagnostic procedure coded as their first treatment event, though their effective treatment had not yet started. These data suggest that TTI is likely longer than what is reported to the NCDB. Redefinition of what constitutes surgical treatment should be considered to improve the accuracy of data used in measuring TTI in sarcoma.

Osteoid osteomas of the hands and feet: a series of 71 cases.

Osteoid osteomas typically arise in the long bones of extremities. Patients often report pain relieved by NSAIDS, and radiographic findings are often sufficient for diagnosis. However, when involving the hands/feet, these lesions may go unrecognized or misdiagnosed radiographically due to their small size and prominent reactive changes. The clinicopathologic features of this entity involving the hands and feet are not well-described. Our institutional and consultation archives were searched for all cases of pathologically confirmed osteoid osteomas arising in the hands and feet. Clinical data was obtained and recorded. Seventy-one cases (45 males and 26 females, 7 to 64 years; median 23 years) arose in the hands and feet, representing 12% of institutional and 23% of consultation cases. The clinical impression often included neoplastic and inflammatory etiologies. Radiology studies demonstrated a small lytic lesion in all cases (33/33), the majority of which had a tiny focus of central calcification (26/33). Nearly, all cases demonstrated cortical thickening and/or sclerosis and perilesional edema which almost always had an extent two times greater than the size of the nidus. Histologic examination showed circumscribed osteoblastic lesions with formation of variably mineralized woven bone with single layer of osteoblastic rimming. The most common growth pattern of bone was trabecular (n = 34, 48%) followed by combined trabecular and sheet-like (n = 26, 37%) with only 11 (15%) cases presenting with pure sheet-like growth pattern. The majority (n = 57, 80%) showed intra-trabecular vascular stroma. No case showed significant cytology atypia. Follow up was available for 48 cases (1-432 months), and 4 cases recurred. Osteoid osteomas involving the hands and feet follow a similar age and sex distribution as their non-acral counterparts. These lesions often present with a broad differential diagnosis and may initially be confused with chronic osteomyelitis or a reactive process. While the majority of cases have classic morphologic features on histologic exam, a small subset consists solely of sheet-like sclerotic bone. Awareness that this entity may present in the hands and feet will help pathologists, radiologists, and clinicians accurately diagnose these tumors.

Aneurysmal bone cyst: a review.

Aneurysmal bone cyst (ABC) is a benign locally destructive bone neoplasm composed of multi-loculated blood-filled cystic spaces. The most common sites of involvement are the meta-diaphysis of the long bones and posterior elements of the vertebrae. Secondary, ABC-like changes can complicate a variety of other benign and malignant primary bone neoplasms, including giant cell tumor, fibrous dysplasia, and osteosarcoma. About two-third of primary ABCs have a rearrangement of the USP6 gene, which is not present in the ABC-like changes that occur secondary to other primary bone tumors (i.e., secondary ABC). Primary ABC of bone carries a variable but generally high rate of local recurrence. This paper provides an overview of the pathophysiology, clinical presentation, radiographic and pathologic findings, treatment, and prognosis of ABC.

Primary Bilateral Intraosseous Rosai-Dorfman Disease.

Rosai-Dorfman disease (RDD) is a rare histiocytic proliferative disease of unknown etiology. Typically presenting with cervical adenopathy and constitutional symptoms, RDD involves bone in less than 10% of cases-and rarely presents as a primary intraosseous lesion. In this report, we describe the presentation of primary, bilateral intraosseous RDD, the first known case in the literature. Asymmetrically involving the lateral femoral condyles of a 59-year-old male, the lesion was discovered incidentally during evaluation and workup for giant cell tumor of bone involving the left tibia. Confirmation of the diagnosis required multiple biopsies and extensive evaluation-reflecting the diagnostic challenge associated with this case. We discuss the clinical, radiological, and pathological findings that allowed us to establish the diagnosis-as well as key differential diagnostic considerations and clinical outcome to date.

Adjuvant Radiation after Primary Resection of Atypical Lipomatous Tumors of the Extremity Reduces Local Recurrence but Increases Complications: A Multicenter Evaluation.

Background: Radiation after resection of an atypical lipomatous tumor (ALT) is controversial. This study evaluates local control and complications after the first resection of ALTs of the extremity with or without adjuvant radiation. Methods: A dual institution, retrospective review of patients treated from 1995 to 2020 with first-time resection of an ALT in the extremity was performed. In total, 102 patients underwent adjuvant radiation (XRT group) and 68 patients were treated with surgery alone (no-XRT group). The median follow-up time was 4.6 years (interquartile range (IQR) 2.0-7.3 years). The median radiation dose was 60 Gy (IQR 55-66 Gy). Univariable and multivariable analyses evaluated the association of patient, tumor, and treatment variables with recurrence and complications. Kaplan-Meier analysis evaluated local recurrence-free survival (LRFS) and time to complication. Results: The overall incidence of local recurrence was 1% (1/102) in the XRT group and 24% (16/68) in the no-XRT group (p < 0.001). The median time-to-recurrence was 8.2 years (IQR 6.5-10.5 years). In the XRT and the no-XRT groups, 5-yr LRFS was 98% and 92% (p=0.21) and 10-yr LRFS was 98% and 41% (p < 0.001), respectively. The absence of radiation (HR = 23.63, 95% CI (3.09-180.48); p < 0.001) and R2 surgical resection margins (HR = 11.04, 95% CI (2.07-59.03); p < 0.001) incurred a 23-fold and 11-fold increased risk of local recurrence, respectively, while tumor size, depth, location, and neurovascular involvement were not found to be independent predictors of recurrence. The complication rate was 37% (38/102) in the XRT group and 10% (7/68) in the no-XRT group (p < 0.001). Eight patients (8/102, 8%) required surgical management for complication in the XRT group compared with two patients (2/68, 3%) in the no-XRT group (p=0.10). Higher radiation dose had a modest correlation with increased severity of complication (ρ=0.24; p=0.02). Conclusions: Adjuvant radiation after first-time resection of an ALT of the extremity was associated with a significantly reduced risk of local recurrence but a three-fold increase in complication rate. These data support a 10-year follow-up for these patients and inform a notable clinical trade-off if considering adjuvant radiation for this tumor with recurrent potential.

Tumor-Infiltrating Lymphocytes and Cancer Markers in Osteosarcoma: Influence on Patient Survival.

Osteosarcoma (OST) is the most common type of high-grade primary bone tumor, which mainly affects young adults. The current standard of care for OST combines surgical resection with chemotherapy. The clinical outcomes and the current options to treat OST patients are unsatisfactory and novel treatment strategies are needed. The crosstalk between tumor cells and immune cells is essential to the OST microenvironment. Despite the efforts that have been made to address the importance of immune-related factors in OST, there is still a lot to understand. The purpose of the current study was to evaluate the tumor-infiltrating lymphocytes (TIL), the expression of proteins involved in tumor biology, and their impact on the clinical outcome of OST patients. We studied 93 samples of OST patients using immunohistochemistry and histomorphometry. We looked for the infiltration of CD3+, CD4+, CD8+, TIA1+ and CD20+ cells and for the expression of CD44 standard (CD44s) and variant 6 (CD44v6), CD95/Fas, Fas-L, p53 and p-glycoprotein. All the parameters were analyzed for the influence on the occurrence of death and metastasis, plus patient overall survival (OS) and progression-free survival (PFS). The effect of sex, age, tumor location (distal femur or proximal tibia) and the combination with neoadjuvant chemotherapy was also assessed. Our results suggest that the presence of tumor-infiltrating CD4+ cells provides protection to OST patients, and that CD8+ cells have a significant impact on the patient's overall survival (OS) and progression-free survival (PFS), which is more evident in male patients. In addition, a strong association between tumor-infiltrating CD4+ cells and the presence of CD44s expression in tumor samples was observed. Analysis of TIL and tumor markers related to tumor biology could be useful to stratify patients and monitor the response to therapy, as well as to assist with the development of immunotherapy strategies to improve the effects of cytotoxic TIL to eradicate the tumor cells.

Osteofibrous Dysplasia and Adamantinoma.

For decades, the diagnosis, treatment, and even pathogenesis of the osteofibrous dysplasia/osteofibrous dysplasia-like adamantinoma/classic adamantinoma spectrum of neoplasms have been controversial. Herein, we discuss and illustrate the radiographic and histologic spectrum, differential diagnoses, unifying chromosomal and molecular abnormalities, and current controversies and treatment recommendations for each entity.

Eruptive agminated nevi in a successfully treated Langerhans cell histiocytosis patient.

A 7-year-old girl with a history of Langerhans cell histiocytosis (LCH), in remission, presented with the sudden appearance of multiple, agminated nevi. Skin biopsy revealed a benign junctional nevus, without recurrence of LCH. Subsequent immunohistochemical testing of both the skin and iliac wing biopsies demonstrated a BRAF V600E mutation. MAPK pathway mutations have been implicated in both LCH and nevogenesis.

Clear Cell Chondrosarcoma with Rib Cage Metastasis: Case Report.

Clear cell chondrosarcoma is a rare histological subtype of chondrosarcoma, usually with a relatively non-aggressive clinical course. However, infrequently they may relapse and metastasize. We describe a case of a male patient, 53 years old, with rib cage metastases of a clear cell chondrosarcoma 11 years after the first surgical intervention, and review the literature.

Diagnostic Utility of a Custom 34-Gene Anchored Multiplex PCR-Based Next-Generation Sequencing Fusion Panel for the Diagnosis of Bone and Soft Tissue Neoplasms With Identification of Novel USP6 Fusion Partners in Aneurysmal Bone Cysts.

CONTEXT.­: Bone and soft tissue tumors are heterogeneous, diagnostically challenging, and often defined by gene fusions. OBJECTIVE.­: To present our experience using a custom 34-gene targeted sequencing fusion panel. DESIGN.­: Total nucleic acid extracted from formalin-fixed, paraffin-embedded (FFPE) tumor specimens was subjected to open-ended, nested anchored multiplex polymerase chain reaction and enrichment of 34 gene targets, thus enabling detection of known and novel fusion partners. RESULTS.­: During a 12-month period, 147 patients were tested as part of routine clinical care. Tumor percentage ranged from 10% to 100% and turnaround time ranged from 3 to 15 (median, 7.9) days. The most common diagnostic groups were small round blue cell tumors, tumors of uncertain differentiation, fibroblastic/myofibroblastic tumors, and adipocytic tumors. In-frame fusion transcripts were identified in 64 of 142 cases sequenced (45%): in 62 cases, the detection of a disease-defining fusion confirmed the morphologic impression; in 2 cases, a germline TFG-GPR128 polymorphic fusion variant was detected. Several genes in the panel partnered with multiple fusion partners specific for different diagnoses, for example, EWSR1, NR4A3, FUS, NCOA2, and TFE3. Interesting examples are presented to highlight how fusion detection or lack thereof was instrumental in establishing accurate diagnoses. Novel fusion partners were detected for 2 cases of solid aneurysmal bone cysts (PTBP1-USP6, SLC38A2-USP6). CONCLUSIONS.­: Multiplex detection of fusions in total nucleic acid purified from FFPE specimens facilitates diagnosis of bone and soft tissue tumors. This technology is particularly useful for morphologically challenging entities and in the absence of prior knowledge of fusion partners, and has the potential to discover novel fusion partners.

Clinicopathologic characterization of malignant chondroblastoma: a neoplasm with locally aggressive behavior and metastatic potential that closely mimics chondroblastoma-like osteosarcoma.

Chondroblastoma is currently classified as a benign neoplasm; however, chondroblastoma and chondroblastoma-like osteosarcoma have morphologic overlap, raising the possibility that some tumors diagnosed as chondroblastoma-like osteosarcoma might actually represent malignant chondroblastoma. The H3F3B K36M point mutation, which has not been reported in osteosarcoma, is identified in 95% of chondroblastomas and is reliably detectable by immunohistochemistry (IHC). We reviewed 11 tumors diagnosed as atypical chondroblastoma, malignant chondroblastoma, or chondroblastoma-like osteosarcoma (median follow-up: 8.8 years; range: 4 months-26.4 years). Seven chondroblastomas with cytologic atypia and permeative growth were designated "malignant chondroblastoma"; six were H3K36M-positive by IHC. Relative to conventional chondroblastoma, malignant chondroblastoma occurred in older individuals (median: 52 years; range: 29-57 years) and arose at unusual sites. Three of four tumors with long-term follow-up recurred, and one patient died of widespread metastases. One was found to have chromosomal copy number alter4ations and a SETD2 mutation in addition to H3F3B K36M. The four remaining tumors were classified as chondroblastoma-like osteosarcoma. Chondroblastoma-like osteosarcoma occurred in younger patients (median: 21 years; range: 19-40 years) than malignant chondroblastoma. In contrast to malignant chondroblastoma, all had regions of malignant cells forming bone. Two of three patients with long-term follow-up developed recurrences, and two died of disease, one with widespread metastases. No mutations in H3F3A/H3F3B were detected by Sanger sequencing. While malignant chondroblastoma and chondroblastoma-like osteosarcoma show significant morphologic overlap, they have distinct clinical presentations and genetic findings. When considering this challenging differential diagnosis, IHC using histone H3 mutation-specific antibodies is a critical diagnostic adjunct.

Primary pulmonary artery sarcoma in the pediatric patient: Review of literature and a case report.

Primary pulmonary artery sarcoma (PAS) is extremely rare in children. Nevertheless, distinguishing primary PAS from pulmonary embolism is critical to a child's survival. Primary PAS is commonly misdiagnosed as a pulmonary embolism due to similar presenting symptoms and radiographic findings. However, compared to adults, pulmonary embolism is rare in children, especially in patients who do not have predisposing factors or hypercoagulable state. We present a child with primary PAS which mimicked pulmonary embolism on presentation but eventually was resected and is doing well 5 years after resection. In the absence of predisposing factors or hypercoagulable state, solid tumors such as primary PAS should be considered when assessing a pediatric patient with presumed pulmonary embolism.

Time to Treatment Initiation and Survival in Adult Localized High-Grade Bone Sarcoma.

OBJECTIVE: Few studies have evaluated the prognostic implication of the length of time from diagnosis to treatment initiation in bone sarcoma. The purpose of this study is to determine if time to treatment initiation (TTI) influences overall survival in adults diagnosed with primary bone sarcoma. METHODS: A retrospective analysis of the National Cancer Database identified 2,122 patients who met inclusion criteria with localized, high-grade bone sarcoma diagnosed between 2004 and 2012. TTI was defined as length of time in days from diagnosis to initiation of treatment. Patient, disease-specific, and healthcare-related factors were also assessed for their association with overall survival. Kruskal-Wallis analysis was utilized for univariate analysis, and Cox regression modeling identified covariates associated with overall survival. RESULTS: Any 10-day increase in TTI was not associated with decreased overall survival (hazard ratio (HR) = 1.00; P=0.72). No differences in survival were detected at 1 year, 5 years, and 10 years, when comparing patients with TTI = 14, 30, 60, 90, and 150 days. Decreased survival was significantly associated (P < 0.05) with patient ages of 51-70 years (HR = 1.66; P=0.004) and > 71 years (HR = 2.89; P < 0.001), Charlson/Deyo score ≥2 (HR = 2.02; P < 0.001), pelvic tumor site (HR = 1.58; P < 0.001), tumor size >8 cm (HR = 1.52; P < 0.001), radiation (HR = 1.81; P < 0.001) as index treatment, and residing a distance of 51-100 miles from the treatment center (HR = 1.30; P=0.012). Increased survival was significantly associated (P < 0.05) with chordoma (HR = 0.27; P=0.010), chondrosarcoma (HR = 0.75; P=0.002), treatment at an academic center (HR = 0.64; P=0.039), and a private (HR = 0.67; P=0.006) or Medicare (HR = 0.71; P=0.043) insurer. A transition in care was not associated with a survival disadvantage (HR = 0.90; P=0.14). CONCLUSIONS: Longer TTI was not associated with decreased overall survival in localized, high-grade primary bone sarcoma in adults. This is important in counseling patients, who may delay treatment to receive a second opinion or seek referral to a higher volume sarcoma center.

Primary Intraosseous Synovial Sarcoma with Molecular Confirmation: Expanding and Clarifying the Spectrum of This Rare Neoplasm.

Synovial sarcoma is a well-known malignant tumor usually originating within deep soft tissues of the lower extremities of adolescents and young adults. Rare radiologically confirmed examples of primary bone synovial sarcoma have been documented, generally in isolated case reports. Herein, we report two cases of primary intraosseous synovial sarcoma, with molecular confirmation, involving the left humerus of a 45-year-old female and the right fourth metatarsal bone in a 36-year-old male. Additionally, we clarify the spectrum of primary intraosseous synovial sarcoma by separately analyzing reported cases with radiographic confirmation of bone origin and molecular support for the diagnosis. There are clinicopathologic differences between those tumors with documented molecular confirmation and those lacking such confirmation, specifically regarding their anatomic distribution (p < 0.0001). Regarding the radiology of our two cases, the humeral lesion appeared almost entirely intramedullary without soft tissue extension; the midfoot lesion demonstrated a destructive, metatarsal-centered bone lesion, initially thought clinically to represent primary bone osteosarcoma. The diagnoses of monophasic synovial sarcoma were rendered via core needle biopsies, with molecular FISH confirmation of SYT gene rearrangement. Clinical follow-up data was only available for the female patient with the primary humeral lesion, who underwent surgical resection, with no local recurrence or distant metastasis at 7 months postsurgery. To our knowledge, these are the first reported examples of molecularly confirmed, primary intraosseous synovial sarcomas of the humerus and metatarsal bones. Primary intraosseous synovial sarcomas with molecular confirmation differ clinically from those lacking it; however, the demographic features and metastatic potential appear similar to primary soft tissue synovial sarcoma.