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Dive into the research topics where Riikka Huuhtanen is active.

Publication


Featured researches published by Riikka Huuhtanen.


British Journal of Surgery | 2007

Impact of the smallest surgical margin on local control in soft tissue sarcoma

Mika Sampo; Maija Tarkkanen; Riikka Huuhtanen; Erkki Tukiainen; Tom Böhling; Carl Blomqvist

The aim was to review a single‐institution experience of a prospective treatment protocol for soft tissue sarcoma of the extremity and trunk wall, with particular focus on the smallest surgical margin leading to local control.


Genes, Chromosomes and Cancer | 1998

Genetic imbalances in 67 synovial sarcomas evaluated by comparative genomic hybridization

Jadwiga Szymanska; Massimo Serra; Björn Skytting; Olle Larsson; Martti Virolainen; M. Åkerman; Maija Tarkkanen; Riikka Huuhtanen; Piero Picci; Patrizia Bacchini; Sirpa Asko-Seljavaara; Inkeri Elomaa; Sakari Knuutila

We used comparative genomic hybridization (CGH) to evaluate DNA sequence copy number changes in 67 synovial sarcomas of both monophasic and biphasic histological subtypes. Changes (mean among aberrant cases: 4.7 aberrations/tumor; range: 1–17), affecting most often entire chromosomes or chromosome arms, were detected in 37 sarcomas (55%). Gains and losses were distributed equally, but different chromosomes were affected with variable frequencies. The most frequent aberrations, each detected in 9–11 of 67 tumors, were gain of 8q and gain at 12q (12q14‐15 and 12q23‐qter), loss of 13q21‐31, and loss of 3p. Other frequent changes (in 7 or 8 cases) included gains at 2p, 1q24‐31, and 17q22‐qter, and losses at 3cen‐q23 and 10q21. High‐level amplifications were seen in 7 cases. A total of 16 regions were detected. Two of them, 8p12‐qter and 21q21‐qter, seen in 4 and 2 tumors, respectively, were recurrent. No aberrations specific to histological subtype were identified. However, genetic changes in the monophasic tumors were more complex and numerous (mean among aberrant cases: 5.3 aberrations/tumor; range: 1–17) than in the biphasic tumors (mean: 2.5 aberrations/tumor; range: 1–5), and high‐level amplifications occurred more frequently. All but 1 of the sarcomas showing high‐level amplification were of the monophasic subtype. These findings may reflect differences in the pathogenesis and biological behavior of both histological subtypes of synovial sarcoma. Genes Chromosomes Cancer 23:213–219, 1998.


British Journal of Cancer | 1999

Comparison of the Ki-67 score and S-phase fraction as prognostic variables in soft-tissue sarcoma

Riikka Huuhtanen; Carl Blomqvist; Tom Wiklund; Tom Böhling; Martti Virolainen; Erkki Tukiainen; Bernhard Tribukait; Leif C. Andersson

SummaryImmunohistochemically determined Ki-67 scores and flow cytometrically determined S-phase fractions were successfully evaluated from the primary tumours of 123 patients with soft-tissue sarcoma. All patients had either limb or superficial trunk tumours. Ki-67 score correlated strongly with ploidy, S-phase fraction and grade. Ki-67 did not correlate with the size of the primary tumour. When analysed as a continuous variable, Ki-67 was a stronger predictor of both metastasis-free survival and disease-specific overall survival (P= 0.003 and 0.04 respectively) than was the S-phase fraction (P= 0.06 and 0.07 respectively). We tested the relevance of different cut-point values by dividing the whole material into two parts at every 10% (e.g. 10% of patients vs. the remaining 90%, 20% vs. 80%, etc.). We counted the relative risk and confidence interval at all these cut-off points. Ki-67 had good prognostic discriminating power irrespective of the cut-point value, but S-phase fraction lost its prognostic power at higher cut-point values. In conclusion, we found that Ki-67 is a useful prognostic tool in the treatment of soft-tissue sarcoma patients irrespective of the cut-point value. S-phase fraction can be used at lower cut-point values.


Genes, Chromosomes and Cancer | 1999

Comparison of genetic changes in primary sarcomas and their pulmonary metastases.

Maija Tarkkanen; Riikka Huuhtanen; Martti Virolainen; Tom Wiklund; Sirpa Asko-Seljavaara; Erkki Tukiainen; Mauri Lepäntalo; Inkeri Elomaa; Sakari Knuutila

The aims of the present study were to compare genetic aberrations in primary sarcomas and their pulmonary metastases and to explore the pathways associated with disease spreading. The primary tumor and its subsequent pulmonary metastasis of 22 patients were analyzed by comparative genomic hybridization. All samples were obtained before the initiation of chemo‐ or radiotherapy. The mean total number of aberrations per tumor was 7.6 (range, 0–17) in primary tumors and 7.5 (range, 0–19) in metastases. The mean numbers of high‐level amplifications per tumor were similar (0.32 in primary tumors and 0.36 in metastases). The frequencies of the most common aberrations were relatively similar in primary tumors and metastases: the most frequent gain affected 1q (minimal common regions 1q21–q23 in 36% of primary tumors and 1q21 in 45% of metastases). The most frequent losses were detected at 9p (9p22–pter in 32% of primary tumors and 9p21–pter in 32% of metastases), 10p (10p11.2–p12 in 41% of primary tumors and 10p11.2–pter in 32% of metastases), 11q (11q23–qter in 36% of primary tumors and 32% of metastases), and 13q (13q14–q21 in 45% of primary tumors and 50% of metastases). No aberrations specific to metastases were detected. An increase in the total number of changes during progression was a predominant feature in a majority of these paired samples. Also, the number of differences in the genetic profile outnumbered common changes in a majority of the samples. However, despite the heterogeneous and numerous changes, all pairs with aberrations in both specimens had some shared alterations in both samples. Genes Chromosomes Cancer 25:323–331, 1999.


Plastic and Reconstructive Surgery | 2004

Soft-tissue sarcomas of the upper extremity: surgical treatment and outcome.

Pentscho Popov; Erkki Tukiainen; Sirpa Asko-Seljavaara; Riikka Huuhtanen; Martti Virolainen; Pekka Virkkunen; Carl Blomqvist

The objective of this retrospective follow-up study was to evaluate the outcome of patients with soft-tissue sarcoma treated by the authors’ protocol, which consists of a selective combination of conservative surgery and radiotherapy. Patients who relapsed were especially evaluated to improve treatment results. The authors examined 80 patients with local soft-tissue sarcoma in the upper extremity referred to their multidisciplinary group. Fifteen patients were referred for first or subsequent local recurrence, and 65 patients were treated for primary tumor. The goal of treatment was local control and preservation of a functional limb. Wide excision was attempted. If the margin was less than 2.5 cm, postoperative radiotherapy was administered. Eighty-five percent of the patients were treated by limb salvage. Thirty patients needed reconstructive procedures such as pedicled (20 patients) or free flaps (10 patients). No free flaps were lost. The 5-year disease-specific overall survival rate was 75 percent, the local recurrence-free survival rate was 79 percent, and the metastasis-free survival rate was 68 percent. In univariate analysis, prognostic factors for local recurrence were extracompartmental site; for development of metastases, large size and extracompartmental site; and for decreased disease-specific overall survival, large size and extracompartmental site. Intramuscular, cutaneous, and subcutaneous tumors had a 5-year local control rate of 100 percent, and extracompartmental tumors had a local control rate of 69 percent. Extracompartmental tumors clearly have the worst prognosis and should be the main target for improving treatment strategies. After exclusion of patients with inadequate treatment according to the authors’ protocol, the local control rate at 5 years was 90 percent. Strict adherence to treatment protocol should be practiced.


British Journal of Cancer | 1999

A high proliferation rate measured by cyclin A predicts a favourable chemotherapy response in soft tissue sarcoma patients.

Riikka Huuhtanen; Tom Wiklund; Carl Blomqvist; Tom Böhling; Martti Virolainen; Bernhard Tribukait; Leif C. Andersson

SummaryA small but not insignificant number of patients experience a prolonged survival after treatment of metastatic soft tissue sarcoma. This must be weighed against the majority of the patients who benefit little from the therapy, but nevertheless experience its side-effects. It would therefore be of utmost importance to be able to screen for those patients who respond to the treatment. Since proliferating cells are more sensitive to chemotherapy than non-proliferative cells, we measured the proliferation rate of the primary tumour of 55 soft tissue sarcoma patients with locally advanced or metastatic disease by determining the flow cytometric S phase fraction and immunohistochemical Ki-67 and cyclin A scores. S phase fraction or Ki-67 score did not predict chemotherapy response or progression-free survival. A high cyclin A score, however, correlated with a better chemotherapy response (P = 0.02) and longer progression-free survival time (P = 0.04). Our results suggest that a high cyclin A score predicts chemotherapy sensitivity.


Cancer | 1996

S-Phase Fraction of 155 Soft Tissue Sarcomas Correlation with Clinical Outcome

Riikka Huuhtanen; Carl Blomqvist; Tom Wiklund; Martti Virolainen; A. Inkeri Elomaa; Yi Pan; Bernhard Tribukait

Traditionally, grade is considered the most important prognostic factor for soft tissue sarcomas (STS). However, because of the alleged difficulties in reproducibility of grading, new, objectively determined prognostic factors would be of value. The aim of our study was to establish if S‐phase fraction (SPF) measured with flow cytometry was of prognostic significance for STS.


Annals of Oncology | 2010

Docetaxel versus docetaxel alternating with gemcitabine as treatments of advanced breast cancer: final analysis of a randomised trial

Heikki Joensuu; L. Sailas; T. Alanko; K. Sunela; Riikka Huuhtanen; Meri Utriainen; R. Kokko; Petri Bono; T. Wigren; Seppo Pyrhönen; Taina Turpeenniemi-Hujanen; R. Asola; M. Leinonen; M. Hahka-Kemppinen; Pirkko-Liisa Kellokumpu-Lehtinen

Background: Alternating administration of docetaxel and gemcitabine might result in improved time-to-treatment failure (TTF) and fewer adverse events compared with single-agent docetaxel as treatment of advanced breast cancer. Patients and methods: Women diagnosed with advanced breast cancer were randomly allocated to receive 3-weekly docetaxel (group D) or 3-weekly docetaxel alternating with 3-weekly gemcitabine (group D/G) until treatment failure as first-line chemotherapy. The primary end point was TTF. Results: Two hundred and thirty-seven subjects were assigned to treatment (group D, 115; group D/G, 122). The median TTF was 5.6 and 6.2 months in groups D and D/G, respectively (hazard ratio 0.85, 95% confidence interval 0.63–1.16; P = 0.31). There was no significant difference in time-to-disease progression, survival, and response rate between the groups. When adverse events were evaluated for the worst toxicity encountered during treatment, there was little difference between the groups, but when they were assessed per cycle, alternating treatment was associated with fewer severe (grade 3 or 4) adverse effects (P = 0.013), and the difference was highly significant for cycles when gemcitabine was administered in group D/G (P < 0.001). Conclusion: The alternating regimen was associated with a similar TTF as single-agent docetaxel but with fewer adverse effects during gemcitabine cycles.


Modern Pathology | 2001

Primary soft tissue sarcoma and its local recurrence: genetic changes studied by comparative genomic hybridization.

Pentscho Popov; Mortti Virolainen; Erkki Tukiainen; Sirpa Asko-Scljavaara; Riikka Huuhtanen; Sakari Knuutila; Maija Tarkkanen

The aims of this study were to compare genetic aberrations in primary soft-tissue sarcomas and their local recurrences and to evaluate the genetic changes occurring during tumor progression. A primary soft-tissue sarcoma and its subsequent local recurrence were analyzed in 20 tumor pairs by comparative genomic hybridization. The samples were obtained before application of radio- or chemotherapy. Copy number aberrations were detected in 50% of the primary tumors and in 70% of the local recurrences. In primary tumors, the mean number of changes was 2.45 (range, 0 to 11) whereas in local recurrences, it was 5.05 (range, 0 to 17). The mean increase of changes from primary tumor to local recurrence was 2.6 per tumor pair (P = .02). Gains predominated over losses in both primary tumors and their local recurrences. The number of high-level amplifications was twofold in local recurrences. The most frequent gain affected 5p14-p15.1 (10% of primary tumors, 25% of local recurrences) and the most frequent loss, 9p (9p21-pter in 5% of primary tumors; 9p22-pter in 30% of local recurrences). In conclusion, our results show an increase in the number of genetic changes in local recurrences, due to tumor progression. Loss at 9p and gains at 5p and 20q were more frequent in local recurrences, and high-level amplification of 18p11.3 was not detected in any of the primary tumors. Although all these alterations were not specific to local recurrences, they may represent changes important during tumor progression.


British Journal of Cancer | 1996

Growth rate of lung metastases and S-phase fraction as determined by flow cytometry from the primary tumour in 25 patients with bone or soft-tissue sarcomas

Carl Blomqvist; Riikka Huuhtanen; Y Pan; Tom Wiklund; Maija Tarkkanen; Martti Virolainen; Bernhard Tribukait

A significant correlation (r = -0.48) was found between the logarithm of the S-phase fraction of the primary tumour (SPF) and the logarithm of the doubling time of lung metastases (T2). The estimated median cell loss factor was 88% (range 35-99%).

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Martti Virolainen

Helsinki University Central Hospital

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Tom Wiklund

University of Helsinki

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Maija Tarkkanen

Helsinki University Central Hospital

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Sirpa Asko-Seljavaara

Helsinki University Central Hospital

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Pentscho Popov

Helsinki University Central Hospital

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