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Featured researches published by Tero Kivelä.


Ophthalmology | 2000

Tumor doubling times in metastatic malignant melanoma of the uvea: Tumor progression before and after treatment

Sebastian Eskelin; Seppo Pyrhönen; Paula Summanen; Marjo Hahka-Kemppinen; Tero Kivelä

OBJECTIVE To obtain estimates of growth rate of metastatic uveal melanoma to infer appropriate follow-up programs and to assess the impact of current chemoimmunotherapy regimens. DESIGN Retrospective case series. PARTICIPANTS Of 70 consecutive patients diagnosed with metastatic uveal melanoma from 1986 through 1998, 37 patients who attended regular follow-up and had measurable metastases were eligible for this study. METHODS Tumor doubling time (DT) was calculated by the Schwartz formula using three presumed sizes of metastasis at last negative follow-up. DT was compared according to tumor characteristics, and time of micrometastasis was estimated. MAIN OUTCOME MEASURES Doubling time of untreated and treated metastases. RESULTS Doubling time of untreated metastases ranged from 34 to 220 days (median, 63 days). Regardless of the presumed size of metastasis at last screening, two thirds of the metastases had a DT between 30 and 80 days. No significant correlation between DT and the observed disease-free interval was detected. Assuming constant growth rate, most metastases had predictably initiated within 5 years before primary treatment. Mean DT during active treatment of metastases in 18 patients who did not show an objective response ranged from 25 to 2619 days (median, 255 days). CONCLUSIONS Based on the estimated growth rates, a rational follow-up interval to detect metastatic uveal melanoma would be 4 to 6 months. Primary uveal melanomas that develop clinically detectable metastasis after conservative therapy may micrometastasize several years before treatment. These estimates are rough and must be confirmed by prospective studies. Current chemoimmunotherapy regimens slow down the growth rate of metastases even if objective response is not obtained.


British Journal of Ophthalmology | 2009

The epidemiological challenge of the most frequent eye cancer: retinoblastoma, an issue of birth and death

Tero Kivelä

Many papers on retinoblastoma open with a statement that it is the most common primary intraocular cancer in children and a rare disease. True enough. After reflecting a little longer on the epidemiology of eye cancer, however, this statement probably should be revised to read: “retinoblastoma is the most frequent primary intraocular cancer and is gaining importance rapidly.” Let us substantiate this claim and evaluate its consequences in some detail. First, just how frequent is retinoblastoma? Not an easy question to answer because investigators are estimating its incidence in many ways. A recent issue featured two papers on the subject from the Western hemisphere. MacCarthy and coworkers,1 who analysed data from 1601 children with retinoblastoma diagnosed in England, Scotland and Wales between 1963 and 2002, arrive at an annual incidence rate of 3.5 per million children less than 15 years of age. Broaddus and colleagues2 from the USA estimate the rate to be 11.8 per million children below 5 years of age, based on 658 entries in the Surveillance, Epidemiology, and End Results (SEER) programme database from 1975 to 2004. MacCarthy and coworkers also provide a cumulative incidence estimate of 53 per million for the first 14 years of life, which is useful because by that age, essentially all retinoblastomas have been detected, and they report that 95% of tumours were diagnosed before the age of 5 years.1 Presuming that this percentage is constant, one can calculate the corresponding estimate to be 62 per million for the SEER study. Although they are of the same order of magnitude, the estimates, or any estimate based on the number of children of particular age, will be influenced by differences in child and adolescent mortality between countries, the more so the wider is the age cohort considered. Because retinoblastoma is …


Journal of Clinical Oncology | 1999

Trilateral Retinoblastoma: A Meta-Analysis of Hereditary Retinoblastoma Associated With Primary Ectopic Intracranial Retinoblastoma

Tero Kivelä

PURPOSE To obtain refined knowledge regarding trilateral retinoblastoma (TRb), which is a syndrome that consists of hereditary retinoblastoma associated with an intracranial neuroblastic tumor. MATERIALS AND METHODS Using a systematic literature review, we contacted authors to obtain missing information. Data from 106 children were used in a meta-analysis including frequency distributions and Kaplan-Meier survival curves. RESULTS TRb showed no sex predilection. Median age at diagnosis of retinoblastoma was 5 months (range, 0 to 29 months); age at diagnosis was younger among 47 children (47%) with familial retinoblastoma compared with age at diagnosis among 52 children (53%) with sporadic retinoblastoma (2 v 6.5 months, P <.0001). TRb usually affected the second or third generation with retinoblastoma. Median time from retinoblastoma to TRb was 21 months (range, 6 months before to 141 months after); time to TRb was longer for 78 (77%) pineal tumors compared with 23 (23%) suprasellar tumors (32 v 6.5 months, P <.0001). The size (27 v 32 mm, P =.57) and prognosis (survival of 9 v 8 months, P =.91) of pineal and suprasellar tumors were similar. TRb was detected earlier (1 v 22 months, P =.0007) and the child survived longer if neuroimaging was routinely performed (16 v 8 months, P =.001), but age at death was similar (36 v 37 months, P =.98). Cumulative 5-year survival (which was likely to indicate cure) was 27% (v 0%) if screening was undertaken. All children whose TRb exceeded 15 mm in size died. CONCLUSION The family history, age at diagnosis, and laterality of retinoblastoma in children with TRb resembled that of ordinary hereditary retinoblastoma. Suprasellar TRb were diagnosed earlier, and may arise earlier, than pineal TRb. Screening by neuroimaging could improve the cure rate if cases of TRb were detected when tumors were 15 mm or smaller in size.


Nature Genetics | 2000

Mutations in KERA, encoding keratocan, cause cornea plana.

Natalia S. Pellegata; José L. Dieguez-Lucena; Tarja Joensuu; Stephanie Lau; Kate Montgomery; Ralf Krahe; Tero Kivelä; Raju Kucherlapati; Henrik Forsius; Albert de la Chapelle

Specialized collagens and small leucine-rich proteoglycans (SLRPs) interact to produce the transparent corneal structure. In cornea plana, the forward convex curvature is flattened, leading to a decrease in refraction. A more severe, recessively inherited form (CNA2; MIM 217300) and a milder, dominantly inherited form (CNA1; MIM 121400) exist. CNA2 is a rare disorder with a worldwide distribution, but a high prevalence in the Finnish population. The gene mutated in CNA2 was assigned by linkage analysis to 12q (refs 4,5), where there is a cluster of several SLRP genes. We cloned two additional SLRP genes highly expressed in cornea: KERA (encoding keratocan) in 12q and OGN (encoding osteoglycin) in 9q. Here we report mutations in KERA in 47 CNA2 patients: 46 Finnish patients are homozygous for a founder missense mutation, leading to the substitution of a highly conserved amino acid; and one American patient is homozygous for a mutation leading to a premature stop codon that truncates the KERA protein. Our data establish that mutations in KERA cause CNA2. CNA1 patients had no mutations in these proteoglycan genes.


Cornea | 2015

Ic3d Classification of Corneal Dystrophies—edition 2

Jayne S. Weiss; H. U. Møller; Anthony J. Aldave; Berthold Seitz; Cecilie Bredrup; Tero Kivelä; Francis L. Munier; Christopher J. Rapuano; Kanwal K. Nischal; Eung Kweon Kim; John E. Sutphin; Massimo Busin; Antoine Labbé; Kenneth R. Kenyon; Shigeru Kinoshita; Walter Lisch

Purpose: To update the 2008 International Classification of Corneal Dystrophies (IC3D) incorporating new clinical, histopathologic, and genetic information. Methods: The IC3D reviewed worldwide peer-reviewed articles for new information on corneal dystrophies published between 2008 and 2014. Using this information, corneal dystrophy templates and anatomic classification were updated. New clinical, histopathologic, and confocal photographs were added. Results: On the basis of revisiting the cellular origin of corneal dystrophy, a modified anatomic classification is proposed consisting of (1) epithelial and subepithelial dystrophies, (2) epithelial–stromal TGFBI dystrophies, (3) stromal dystrophies, and (4) endothelial dystrophies. Most of the dystrophy templates are updated. The entity “Epithelial recurrent erosion dystrophies” actually includes a number of potentially distinct epithelial dystrophies (Franceschetti corneal dystrophy, Dystrophia Smolandiensis, and Dystrophia Helsinglandica) but must be differentiated from dystrophies such as TGFBI-induced dystrophies, which are also often associated with recurrent epithelial erosions. The chromosome locus of Thiel-Behnke corneal dystrophy is only located on 5q31. The entity previously designated as a variant of Thiel-Behnke corneal dystrophy on chromosome 10q24 may represent a novel corneal dystrophy. Congenital hereditary endothelial dystrophy (CHED, formerly CHED2) is most likely only an autosomal recessive disorder. The so-called autosomal dominant inherited CHED (formerly CHED1) is insufficiently distinct to continue to be considered a unique corneal dystrophy. On review of almost all of the published cases, the description appeared most similar to a type of posterior polymorphous corneal dystrophy linked to the same chromosome 20 locus (PPCD1). Confocal microscopy also has emerged as a helpful tool to reveal in vivo features of several corneal dystrophies that previously required histopathologic examination to definitively diagnose. Conclusions: This revision of the IC3D classification includes an updated anatomic classification of corneal dystrophies more accurately classifying TGFBI dystrophies that affect multiple layers rather than are confined to one corneal layer. Typical histopathologic and confocal images have been added to the corneal dystrophy templates.


Progress in Retinal and Eye Research | 2000

Exfoliation syndrome and exfoliation glaucoma

Eija Vesti; Tero Kivelä

Exfoliation syndrome abnormal deposition in the anterior segment of the eye of an unknown substance thought to be related to elastic fibres and basement membrane components is associated with accelerated cataract progression. increased frequency of intraoperative and postoperative complications and increased risk for glaucoma and. therefore, is a clinically important finding. A clear association has been shown with age. The syndrome occurs worldwide but its prevalence seems to vary from country to country. The best-known sign of exfoliation syndrome is deposits of greyish-white material on the anterior lens surface. Sometimes exfoliation material can also be seen at the pupillary border, on the anterior iris surface, corneal endothelium, and on the anterior vitreous face. When clinically detected, exfoliation syndrome is somewhat more often unilateral than bilateral. According to recent investigations clinically unilateral exfoliation syndrome is probably never truly unilateral but rather asymmetric, because exfoliation material has been detected ultrastructurally and immunohistochemically around iris blood vessels of the nonexfoliative fellow eyes. Indeed, electron microscopy identifies in various organs of patients with exfoliation syndrome fibrils similar to those seen in intraocular exfoliation deposits. Other clinical signs associated with exfoliation syndrome are pigment dispersion, transillumination defects of the iris and reduced response to mydriatics. In unilateral exfoliation syndrome, intraocular pressure (IOP) of the exfoliative eye is approximately 2 mmHg higher than IOP of the nonexfoliative fellow eye. Whether elevated IOP, vascular changes or exfoliation syndrome itself is the main factor causing optic nerve head damage and conversion of an exfoliative eye to glaucomatous, is not known. Glaucoma in the exfoliation syndrome has been shown to have a more serious clinical course than in primary open-angle glaucoma (POAG). At the time of diagnosis, IOP and its diurnal variation are generally higher and visual field defects tend to be greater in exfoliation glaucoma than in POAG. Because the decrease in lOP variation and lowering of the mean IOP level has been shown to improve visual field prognosis more in exfoliation glaucoma than in POAG, the glaucomatous process is considered to be more pressure-related in exfoliation glaucoma. Furthermore, progression of optic disc damage has been shown to be similar in exfoliation glaucoma and POAG when lOPs are lowered to a comparable level by the treatment. However, vascular disturbances in the posterior segment of the eye might after all be of equal importance in these two types of glaucoma; optic disc haemorrhages and venous occlusions have been reported to be as frequent in exfoliation glaucoma as in POAG. Perhaps in exfoliation glaucoma circullatory disturbances combined with high IOP lead to a particularly relentlessly progressing form of the disease.


Survey of Ophthalmology | 1990

The Merkel cell and associated neoplasms in the eyelids and periocular region

Tero Kivelä; Ahti Tarkkanen

Merkel cells are clear oval cells in the epidermis and outer root sheaths of hair follicles, which are probably of epithelial origin, share ultrastructural features with neuroendocrine cells, and are found in association with touch receptors. In the eyelid, they occur singly in the epidermis and external root sheaths of hairs and eyelashes, and in specialized touch spots alternating with eyelashes. Their typical electron microscopical and antigenic features include dense-core granules, intranuclear rodlets, spinous processes, and a positive reaction for specific cytokeratins, epithelial membrane antigen, neuron-specific enolase, chromogranin and synaptophysin. Merkel cell carcinoma probably develops from precursor cells which give rise to keratinocytes and Merkel cells, and nearly one out of ten Merkel cell carcinomas occur in the eyelid and periocular region. They tend to be bulging lesions near the lid margin of elderly patients, reddish in color, and erythematous with telangiectatic vessels. The diagnosis is based on the frequent presence of neurofilaments and paranuclear aggregates of intermediate filaments in addition to features typical of normal Merkel cells. The tumor often mimics lymphoma or undifferentiated carcinoma and frequently invades lymphatic vessels. One third of Merkel cell carcinomas recur, almost two thirds give rise to regional node metastases, and up to one half metastasize widely and result in death. Initial treatment should be prompt and aggressive, with wide resection and routine postoperative irradiation. Although metastatic lesions often respond to radiation therapy and cytostatic drugs, these treatments are mainly of palliative value.


American Journal of Human Genetics | 2012

Mutations in CTC1, Encoding the CTS Telomere Maintenance Complex Component 1, Cause Cerebroretinal Microangiopathy with Calcifications and Cysts

Anne Polvi; Tarja Linnankivi; Tero Kivelä; Riitta Herva; James P. Keating; Outi Mäkitie; Davide Pareyson; Leena Vainionpää; Jenni Lahtinen; Iiris Hovatta; Helena Pihko; Anna-Elina Lehesjoki

Cerebroretinal microangiopathy with calcifications and cysts (CRMCC) is a rare multisystem disorder characterized by extensive intracranial calcifications and cysts, leukoencephalopathy, and retinal vascular abnormalities. Additional features include poor growth, skeletal and hematological abnormalities, and recurrent gastrointestinal bleedings. Autosomal-recessive inheritance has been postulated. The pathogenesis of CRMCC is unknown, but its phenotype has key similarities with Revesz syndrome, which is caused by mutations in TINF2, a gene encoding a member of the telomere protecting shelterin complex. After a whole-exome sequencing approach in four unrelated individuals with CRMCC, we observed four recessively inherited compound heterozygous mutations in CTC1, which encodes the CTS telomere maintenance complex component 1. Sanger sequencing revealed seven more compound heterozygous mutations in eight more unrelated affected individuals. Two individuals who displayed late-onset cerebral findings, a normal fundus appearance, and no systemic findings did not have CTC1 mutations, implying that systemic findings are an important indication for CTC1 sequencing. Of the 11 mutations identified, four were missense, one was nonsense, two resulted in in-frame amino acid deletions, and four were short frameshift-creating deletions. All but two affected individuals were compound heterozygous for a missense mutation and a frameshift or nonsense mutation. No individuals with two frameshift or nonsense mutations were identified, which implies that severe disturbance of CTC1 function from both alleles might not be compatible with survival. Our preliminary functional experiments did not show evidence of severely affected telomere integrity in the affected individuals. Therefore, determining the underlying pathomechanisms associated with deficient CTC1 function will require further studies.


British Journal of Ophthalmology | 1996

Radiation related complications after ruthenium plaque radiotherapy of uveal melanoma.

Paula Summanen; Ilkka Immonen; Tero Kivelä; Petri Tommila; Jorma Heikkonen; Ahti Tarkkanen

AIMS/BACKGROUND: To analyse radiation related complications and secondary enucleation after irradiation of malignant uveal melanoma with ruthenium-106 plaques. METHODS: A series of 100 consecutive eyes irradiated in 1981-91 was analysed using the life table method and the Cox proportional hazards model. The median apical and scleral tumour dose was 100 Gy (range 15-200 Gy) and 1000 Gy (range 200-1200 Gy), respectively. The median follow up time was 2.8 and 2.0 years (range 1 month to 10 years) for anterior and posterior segment complications, respectively. RESULTS: The 3 and 5 year probabilities of being without radiation cataract were 73% and 63%, without neovascular glaucoma 91% and 81%, without vitreous haemorrhage 83% and 74%, without radiation maculopathy 85% and 70%, and without radiation optic neuropathy 90% and 88%, respectively. The risk of radiation cataract was highest with large tumour size (T1 + T2 v T3, p = 0.0027; height < or = 5 v > 5 mm, p = 0.029; largest basal diameter (LBD) < or = 15 v > 15 mm, p < 0.0001) and location of anterior tumour margin anterior v posterior to the equator (p = 0.0003); the risk of neovascular glaucoma with large size (T1 + T2 v T3, p = 0.039; LBD < or = 15 mm v 15 mm, p = 0.021); and the risk of maculopathy and optic neuropathy with proximity of the posterior tumour margin to the fovea and the optic disc (< or = 1.5 v > 1.5 mm; p = 0.030 and p = 0.0004, respectively). In Coxs multivariate analysis the strongest risk indicator for radiation cataract (RR 1.5, 95% CI 1.4-1.6) and vitreous haemorrhage (RR 1.6, 95% CI 1.4-1.8) was the height of the tumour; for neovascular glaucoma the TNM class (RR 6.2, 95% CI 2.7-13.8); for radiation maculopathy location of posterior tumour margin within 2 mm from the fovea (RR 3.4, 95% CI 2.0-6.0); and for radiation optic neuropathy location of tumour margin within 1 DD of the optic disc (RR 6.1, 95% CI 3.0-12.4). The 3 and 5 year probabilities of avoiding enucleation were 92% and 85%, respectively. Ten eyes were enucleated--six because of recurrent tumour growth, three because of treatment complications, and one because of mistakenly suspected extraocular growth. CONCLUSION: The results suggest that the frequency of radiation related complications after ruthenium brachytherapy of uveal melanoma is acceptable, in particular as regard irradiation of small and medium sized tumours for which ruthenium therapy generally is recommended.


Ophthalmology | 2003

Iodine brachytherapy as an alternative to enucleation for large uveal melanomas.

Ilkka Puusaari; Jorma Heikkonen; Paula Summanen; Ahti Tarkkanen; Tero Kivelä

PURPOSE To evaluate the safety and efficacy of iodine 125 plaque brachytherapy (IBT) for large uveal melanomas. DESIGN Retrospective, nonrandomized comparative trial (historical control). PARTICIPANTS One hundred twenty-one consecutive patients with a large uveal melanoma according to the Collaborative Ocular Melanoma Study (COMS) criteria who attended a national ocular oncology service. METHODS Ninety-seven patients (80%) underwent primary IBT (mean dose to tumor apex, 87 Gy) with noncollimated 20- to 25-mm plaques. Assessment of metastatic disease at death and visual outcome followed COMS guidelines. Time to low vision (20/70 or worse) and blindness (loss of 20/400 vision) in the study eye were modeled by Cox proportional hazards regression, based on both single- and repeated-failure data sets. Person-years of retained vision were calculated. MAIN OUTCOME MEASURES All-cause and melanoma-specific survival, local and distant recurrence, and preservation of vision and cosmesis. RESULTS Median tumor height was 10.7 mm (range, 4.5-16.8 mm), and largest basal tumor diameter was 16.1 mm (range, 7.3-25.0 mm). The Kaplan-Meier estimate for all-cause and melanoma-specific survival was 62% (95% confidence interval [CI], 49%-72%) and 65% (95% CI, 52%-75%) at 5 years. The corresponding estimate for local tumor recurrence was 6% (95% CI, 2%-14%) and for major cosmetic abnormality was 38% (95% CI, 26%-52%). The median visual acuity in the study eye was 20/100 at baseline and 20/1600 at 2 years after treatment. The Kaplan-Meier estimate for avoiding low vision and blindness was 11% (95% CI, 4%-24%) and 26% (95% CI, 16%-37%) at 2 years, respectively. Tumor height and location entirely posterior to the ora serrata were the most robust predictors of visual loss. In this series, 49 person-years without low vision (median, 0.6 years; range, 0.04-8.2 years) and 111 person-years without blindness (median, 1.0 years; range, 0.03-8.6 years) in the treated eye were conserved. CONCLUSIONS Iodine 125 plaque brachytherapy seems to be a safe and effective alternative to enucleation with regard to survival and local tumor control. It provides a fair chance of preserving the eye with acceptable cosmesis and a reasonable chance of conserving useful vision for 1 to 2 years.

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Dive into the Tero Kivelä's collaboration.

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Paula Summanen

Helsinki University Central Hospital

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Marita Uusitalo

Helsinki University Central Hospital

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Sebastian Eskelin

Helsinki University Central Hospital

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Emma Kujala

Helsinki University Central Hospital

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Bertil Damato

Royal Liverpool University Hospital

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Teemu Mäkitie

Helsinki University Central Hospital

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Päivi Toivonen

Helsinki University Central Hospital

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Seppo Tuomaala

Helsinki University Central Hospital

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