M. Szendröi

GIANT-CELL TUMOUR OF BONE

Giant cell tumour (GCT) is still one of the most obscure and intensively examined tumours of bone. Its histogenesis is uncertain. The histology does not predict the clinical outcome; and there are still many unanswered questions with regard to both its treatment and prognosis. The World Health Organisation has classified GCT as “an aggressive, potentially malignant lesion”, 1 which means that its evolution based on its histological features is unpredictable. Statistically, 80% of GCTs have a benign course, with a local rate of recurrence of 20% to 50%. About 10% undergo malignant transformation at recurrence and 1% to 4% give pulmonary metastases even in cases of benign histology.

Good prognosis of localized osteosarcoma in young patients treated with limb-salvage surgery and chemotherapy

The objective of this report was to estimate long‐term outcome and prognostic factors in children and adolescents with osteosarcoma. A large group of osteosarcoma patients were analyzed at our national oncology center.

Phenotype of bone metastases of non-small cell lung cancer: epidermal growth factor receptor expression and K-RAS mutational status.

Bone metastasis is a frequent complication of lung cancer progression, however, studies on bone metastatic tissues are scanty. Here we have collected a small cohort of 11 non-small cell lung cancer cases where primary tumors and corresponding bone metastases were available for pathological analysis. We have tested two molecular markers: EGFR protein expression and K-RAS mutation at codon 12 using immunohistochemistry and RFLP-PCR, respectively. We have shown that using improved protocols, EGFR protein (both the extracellular as well as the cytoplasmic domain) is readily detectable in decalcified bone tissue. We found that the EGFR expression status is highly similar in bone metastases compared to the primary tumors, although the expression levels may change. Individual comparison of corresponding primary and metastatic NSCLC tissues indicated that downregulation of EGFR was a rare event (2/11) compared to upregulation (4/11) in bone metastases. On the other hand, our data indicate that the K-RAS mutational status of the primary tumor does not predict the status of the bone metastatic tissue of NSCLC, since we have observed both emergence of mutant clones in metastases from wild-type (wt) primary tumors and loss of mutant clones in metastases from mutant primaries in addition to the maintained mutant status. Our data support that at least two progression models occur in NSCLC, the samegene as well as the clonal selection one. It is noteworthy that in NSCLC cases with wtor mutant K-RAS, downregulation of EGFR expression was a rare event although upregulation in bone metastases was observed more frequently in wt K-RAS cases.

Calcitonin therapy of aneurysmal bone cysts.

SummarySeven aneurysmal bone cysts (ABC) were treated with the hormone calcitonin. Six of the cysts, which were hypovascular responded well to the calcitonin administered directly into the cyst. Ossification and rebuilding of the ABC occurred after some months in every case. One hypervascularized ABC, however, failed to respond either to embolotherapy or to the calcitonin hormone treatment. The authors recommend calcitonin administration as a useful non-invasive method for the treatment of hypovascular ABC.

Genomic instability in giant cell tumor of bone. A study of 52 cases using DNA ploidy, relocalization FISH, and array-CGH analysis

Genetic instability in relation to clinical behavior was studied in 52 cases of giant cell tumor of bone (GCTB). Ploidy was determined in the mononuclear cell population by using native cell smears and image cytometry. A relocalization technique allowed fluorescent in situ hybridization (FISH) analysis of CD68‐negative neoplastic cells for numerical changes of chromosomes X, 3, 4, 6, 11, and telomeric association on 11p. Genome‐wide alterations were tested using array comparative genomic hybridization (array‐CGH) on magnetically separated CD68‐negative tumor cells. CTNNB1, TP53, and BCL2 protein expression was also analyzed in formol‐paraffin sections to see if their pathways are involved in the development of chromosomal instability. CD68‐positive histiocytes showed no significant numerical chromosome and telomeric alterations. Based on ploidy values and clinical outcome, we could distinguish five groups as follows: diploid nonrecurrent (n = 20), tetraploid nonrecurrent (n = 6), diploid recurrent (n = 5), tetraploid and/or aneuploid recurrent (n = 14), and malignant cases (n = 7). Random individual‐cell aneusomy was significantly (P < 0.001) more frequent in the recurrent groups (36.01 ± 11.94%) than in the benign nonrecurrent cases (10.65 ± 3.66%). The diploid recurrent group showed significantly (P < 0.001) increased balanced aneusomy compared with the diploid nonrecurrent group and the tetraploid nonrecurrent group represented eusomic polysomy. Array‐CGH and FISH showed clonal aberrations almost exclusively in the malignant group. None of the protein markers tested showed significant correlation with elevated aneuploidy/polysomy (P = 0.56). Our results show that ploidy determination combined with FISH analysis may help predicting recurrence potential of GCTB and suggest that chromosomal abnormalities superimposed on telomeric associations could be responsible for an aggressive clinical course.

Fibrous dysplasia associated with intramuscular myxoma (Mazabraud's syndrome): a long-term follow-up of three cases

Abstract The association between of fibrous dysplasia and intramuscular myxomas is extremely rare. The authors summarize the characteristics of Mazabrauds syndrome, as well as its clinical course on the basis of 24 cases reported in the literature and 3 cases of their own. The syndrome is quite uniform, and mostly occurs in women. Usually the presentation of poliostotic fibrous dysplasia bilaterally in the lower limbs and pelvic bones is followed by the appearance of multifocal intramuscular myxomas in the adjacent muscles, mostly decades later. These hamartomas tend to recur locally or symmetrically in the ipsilateral muscle groups and may reach enormous size without treatment. Malignant transformation (osteosarcoma, fibrosarcoma) on the basis of fibrous dysplasia in Mazabrauds syndrome has been reported in the literature. In our cases, however, in spite of the many recurrences, and the enormous size of the tumours, no malignant transformation was noted in either the fibrous dysplasias or the intramuscular myxomas during the long follow-up time (31 years for fibrous dysplasia and 16 years for myxomas). Early wide surgical excision and a carful long-term follow-up for the often very late recurrences of the myxomas is suggested in Mazabrauds syndrome.

The prognostic significance of DNA cytophotometry and proliferation index (Ki-67) in giant cell tumors of bone

Abstract We studied DNA ploidy by smear cytophotometry and proliferation activity by Ki-67 MIB immunohistochemistry in 69 primary and recurrent giant cell tumors (GCT) from 50 randomly selected patients. The obtained results were evaluated with comparisons made to the available clinical data. From the 46 primary tumors 63% showed diploidy and 37% aneuploidy. A significantly (P=0.026) higher recurrence rate (64%) was observed in aneuploid than in diploid tumors (31%). In the course of the recurrences, both the ratio of aneuploid tumors as well as the proliferation index of the tumors increased, though the degree of the latter was non-significant. Aneuploidy did not mean an unambiguous tendency towards malignant transformation; however, a close follow-up of recurrent aneuploid tumors, and wide excision of the recurrence instead of intralesional curettage are the recommended procedures. The DNA cytophotometry and proliferation index of GCTs – as compared to other histologic examinations – are of prognostic value in the evaluation of the recurrence potential of the GCTs.Résumé Les auteurs ont examiné 1’anomalie chromosomique de DNA á 1’aide de cytophotometrie de frottis; et 1’activité de proliferation par le moyen de 1’immuno- histochimie Ki-67 MIB dans 69 tumeurs de cellules géantes de 50 patients choisis accidentellement. lls ont évalué les résultats en les comparant aux données cliniques disponibles. Parmi les 46 tumeurs primaires 63% ont manifesté un caractère diploide et 37% un caractère aneuploide. On a observé une proportion de recidive significativement plus élevée (P=0.026) dans les tumeurs aneuploides (64%) que dans les tumeurs diploides (31%). Au cours des récidives on a remarquè une augmentation tant dans la proportion des tumeurs aneuploides que dans 1’indice de proliferation mais en ce dernier 1’augmentation n’était pas significative. Le caractère aneuploide ne signifie pas forcément une tendance univoque á la transformation maligne cependant dans les tumeurs aneuploides récidivantes il est nécessaire de suivre la maladie avec beaucoup de soin et comme intervention chirurgicale on conseille une excision large au lieu du curettage intralésionel.

HER-2/neu genotype of breast cancer may change in bone metastasis.

The genotype of breast cancer (BRC) is considered to be relatively stable during tumor progression, accordingly, determination of the estrogen receptor and HER-2/neu status is currently based on the primary tumor. However, recent data suggest that the gene expression profile of the metastatic lesion can be different compared to that of the primary BRC. Accordingly, it is possible that the HER-2/neu status is different in the metastatic lesion and the primary BRC. Since the bone is the most frequent metastatic site during the progression of BRC, we have analyzed the HER-2/neu status of 48 bone metastatic BRC cases by immunohistochemistry and fluorescent in situ hybridization, and it was possible to compare it to the primary site in 23 cases. The frequency of HER-2/neu amplification of BRC in the primary tumors was found to be 17.4% compared to 10.5% in bone metastases. Half of BRC cases with HER-2/neu amplification lost this genotype in bone metastases (4/23 versus 2/23, respectively) and even in the 2 cases where HER-2/neu amplification was retained in the metastases, the copy number was found to be decreased compared to the primary tumor. Based on our data and previous reports in the literature, we suggest to perform HER-2/neu testing both on primary tumor and samples obtained from BRC metastases, at least in case of primary tumors with HER-2/neu amplification, before introduction of HER-2/neu-targeting therapy. (Pathology Oncology Research Vol 12, No 3, 149–152)

Experiences with computer navigated total knee arthroplasty

The successful outcome of total knee arthroplasty (TKA) is very much dependent on precise positioning of the components. Inaccuracy may result in complaints as well as in early mechanical failure. Between March 2003 and September 2005, 69 TKA procedures were performed by the computer navigated technique. The postoperative outcome of this cohort was compared with the same number of TKAs done by the traditional technique. The lower limb anatomical axis was determined in all cases pre- and postoperatively by weight-bearing anteroposterior (AP) and lateral full length X-rays. The positions of femoral and tibial components were recorded. Comparing the data in the navigation group on the AP view, 96.6% of femoral and 96.9% of tibial components and on the lateral view in 95.4% of femoral and in 95.4% of tibial components, the overall postoperative axis in 95.4% fell in the range considered in the literature as optimal. In the traditional group on the AP view, 75.7% of femoral and 68.1% of tibial components and on the lateral view 81.8% of femoral and 63.6% of tibial components, the overall postoperative axis in 60.6% fell between the values considered optimal in the literature. It seems to be proven that the computer navigated total knee arthroplasty technique ensures positioning of components significantly more precisely compared with the traditional surgical method. Accuracy of navigation depends on the software used, on the correct detection of anatomical reference points, and on a potentially uneven thickness of the cement layer during final insertion of the components. The computer navigated technique does not substitute professional skill and experience, since it merely transmits information for the surgeon. The decision is in the hands of the doctor during the entire procedure. The real benefits of the computer navigated technique require further research and can be determined only after long-term analyses.RésuméLe succés de l’arthroplastie totale de genou dépend beaucoup du positionnement des implants. Entre mars 2003 et septembre 2005, 69 athroplasties étaient réalisées avec une technique de navigation informatique. Le devenir de ce groupe était comparé avec le même nombre d’arthroplasties faites avec la technique traditionnelle. L’axe anatomique du membre inférieur était déterminé par des radiographies antéro-postérieures en charge et de profil en extension. Dans le groupe navigué, la position des implants était optimale sur les radio de face pour 96,6% des pièces fémorales, 96,9% des pièces tibiales, sur les radio de profil pour 95,4% des pièces fémorales et tibiales, avec un bon axe dans 95,4% des cas. Dans le groupe traditionnel, les chiffres étaient: 75,7% pour les pièces fémorales, 68,1% pour les pièces tibiales sur les radio de face et 81,8% pour les pièces fémorales, 63,6% pour les pièces tibiales sur les radio de profil avec un bon axe dans 60,6% des cas. Il semble prouvé que l’utilisation de la navigation informatique permette un meilleur positionnement des implants que la méthode conventionnelle. L’efficacité de la navigation dépend du logiciel utilisé, de la précision du repérage anatomique et éventuellement de l’épaisseur de la couche de ciment lors de l’implantation définitive. Cette technique ne remplace pas l’expérience du chirurgien mais transmet des informations fiables, les décisions restant entre les mains de l’opérateur pendant toute l’intervention. Le bénéfice réel sera établi après des études à long terme.

CD8+/FOXP3+-ratio in osteosarcoma microenvironment separates survivors from non-survivors: A multicenter validated retrospective study

Osteosarcoma is the most common primary bone tumor characterized by juvenile onset, tumor heterogeneity, and early pulmonary metastasis. Therapeutic improvement stagnates since more than two decades. Unlike major malignancies, biomarkers as prognostic factors at time of diagnosis are missing. Disease rareness hampers study recruitment of patient numbers sufficient to outweigh tumor heterogeneity. Here, we analyzed in a multicenter cohort the osteosarcoma microenvironment to reduce effects of tumor cell heterogeneity. We hypothesized that quantitative ratios of intratumoral CD8+T-cells to FOXP3+T-cells (CD8+/FOXP3+-ratios) provide strong prognostic information when analyzed by whole-slide imaging in diagnostic biopsies. We followed recommendations-for-tumor-marker-prognostic-studies (REMARK). From 150 included cases, patients with complete treatment were identified and assigned to the discovery (diagnosis before 2004) or the validation cohort (diagnosis 2004–2012). Highly standardized immunohistochemistry of CD8+ and FOXP3+, which was validated by methylation-specific gene analysis, was performed followed by whole-slide analysis and clinical outcome correlations. We observed improved estimated survival in patients with CD8+/FOXP3+-ratios above the median (3.08) compared to patients with lower CD8+/FOXP3+-ratios (p = 0.000001). No patients with a CD8+/FOXP3+-ratio above the third quartile died within the observation period (median follow-up 69 mo). Multivariate analysis demonstrated independence from current prognostic factors including metastasis and response to neoadjuvant chemotherapy. Data from an independent validation cohort confirmed improved survival (p = 0.001) in patients with CD8+/FOXP3+-ratios above 3.08. Multivariate analysis proofed that this observation was also independent from prognostic factors at diagnosis within the validation cohort. Intratumoral CD8+/FOXP3+-ratio in pretreatment biopsies separates patients with prolonged survival from non-survivors in osteosarcoma.