Cellular automata segmentation of brain tumors on post contrast MR images

In this paper, we re-examine the cellular automata(CA) al- gorithm to show that the result of its state evolution converges to that of the shortest path algorithm. We proposed a complete tumor segmenta- tion method on post contrast T1 MR images, which standardizes the VOI and seed selection, uses CA transition rules adapted to the problem and evolves a level set surface on CA states to impose spatial smoothness. Val- idation studies on 13 clinical and 5 synthetic brain tumors demonstrated the proposed algorithm outperforms graph cut and grow cut algorithms in all cases with a lower sensitivity to initialization and tumor type

Analysis of prognostic factors in multiple primary cancer

1980-84 yılları arasında Onkoloji ve Nükleer Tıp Merkezine kabul edilen 9. 180 yeni kanser olgusunun izlemleri sırasında 76 multipi primer kanser olgusu saptandı. Larynx ve akciğer kanserinin birlikte görülmesi en sık karşılaşılan kombinasyonu (% 21). Daha sonra dudak-larynx (% 6.6), cilt-larynx ve cilt-akciğer (% 5.3), meme-over ve meme endometrium (% 4) kombinasyonları geliyordu. Larynx kanseri tüm ve erkek olgularda en sık görülen multipl primer kanser komponenti idi (% 46 ve% 61.2). Larynx kanserini akciğer (% 39.5 ve % 55.1) kanseri izliyordu. Kadınlarda ise meme kanseri en sık karşımıza çıkan komponent idi (% 63). Onbir olguda iki kanser aynı zamanda gelişmişti. Kalan olgularda ise ara 1 ay ile 30 yıl arasında değişiyordu. Olguların % 62 'sinde ara 3 yıldan kısaydı. Sigara içme oranı özellikle erkeklerde ve larynx ve akciğer kanseri olgularında yüksekti. İkinci primer gelişiminden sonra ortalama izlem 1.5 ±0. 2 yıldı. Onyedi olgu son izlemde hastalıksız bulundular(% 22.4). Kadın multi primer kanser olgularında prognoz daha iyiydi. Yaş ve iki kanser arası süre en önemli prognostik faktörler olarak ortaya çıktılar.Seventy-six patients with multiple primary cancers have been found among 9.180 cancer patients admitted to the Center of Oncology & Nuclear Medicine, Okmeydanı Hospital, Istanbul, Turkey between 1980 and 1984. The majority of the patients were male. Combination of larynx cancer and lung cancer was the most commonly seen one. lt was followed by lip cancer-larynx cancer (6. 6 %), skin cancer-larynx cancer and skin cancer-lung cancer (5. 3 %), breast cancer-ovary cancer and breast cancer-endometrial cancer (4 %) combinations. Larynx cancer was the most commonly seen multiple primary cancer component in all patients (46 %) and in male patients (61.2 %). lt was followed by lung cancer, i. e., 39.5 % in all patients and 55.1 % in male patients. In female patients, breası cancer was a component in 63 % of the cases. In eleven patients, two cancers were diagnosed concurrently. In other cases, the interval between two cancers varied between I month and 30 years. The mean interval was 4.1 ±0.6 years. In 62 % of the cases, the interval between two cancers was shorter than 3 years. Smoking rate was especially high in male patients. Mean follow-up after second primary cancer was 1.5 ±0. 2 years. Seventeen patients were found to be disease free at their last follow-up (22. 4 %). The prognosis for female patients with MPC appeared to be better. Age and time interval were the two most important prognostic factors

Primary radiation therapy in early stage larynx cancer

Erken evre larinks kanseri nedeniyle primer radyasyon tedavisi gören 41 olgu retrospektif olarak incelendi. Olguların 17'sinde supraglottik, 24 'ünde glottik tümör saptandı. Büyük çoğunluğunu erkeklerin oluşturduğu(% 93) çalışma grubunda tümörler 18 olguda TİNO (% 44), 19'unda T2NO (% 46) ve 4'ündede T3NO (%10) olarak evlendirildi. Ortalama yaş 55 idi (sınırlar 29-75). Ortalama radyasyon dozu glottik tümörlerde 63±1 Gy, supraglottik tümörlerde 66± 1 Gy ve tüm tümörlerde ise 64±1 Gy idi. Olgularda ortalama izlem süresi 3. 7±0.3 yıldı ( medyan 3.5, sınırlar O. 7-7). Analizin yapıldığı sıra olgulardan yalnızca bir tanesi larinks kanseri nedeniyle kaybedilmişti. Yerel nüks oranı% 14 'dü. Nükse kadar geçen ortalama süre 2.1±1.1 yıldı (sınırlar 0.3-6.3). Bu olguların da tümü kurtarma cerrahisi ile kontrol alt ma alındı. Yalnızca bir olguda ikinci bir primer kanserin geliştiği görüldü (% 3). Erken evre larinks kanserlerinde yerel nüks oranının primer radyasyon tedavisi sonrasında çok düşük olduğuna ve primer radyasyon tedavisinden sonra nüksedecek olguların çoğunun kurtarma cerrahisi ile kontrol altına alınabileceği sonucuna varıldı.Forty-one patients with early stage laryngeal carcinoma who had been treated with primary radiation therapy were analyzed retrospectively. There were 17 patients with supraglottic tumors, 24 with glottic tumors. The majority of the patients were male (93 %). Eighteen patients had TlN O disease (44 %), 19 had T2NO (46 %) and 4 had T3NO (10 %). Mean age was 55 years (range 29-75 years). Mean radiation dose delivered was 63±1 Gy in glottic tumors and 66±1 Gy in supraglottic tumors and 64 ±1 Gy for all tumors. Patients were followed up with a mean of 3. 7±0.3 years (median of 3.5, range O. 7-7 years). Only one patient was known to have died of laryngeal cancer at the time of analysis. Overall local recurrence rate was 14 % . Mean time to recurrence was 2.1 ± 1.1 years (range 0.3-6.3 years). All but one of these cases were controlled after salvage surgery. Only one patient developed a second primary. The incidence of the second primary was 3 % in larynx cancer patients treated with primary radiation therapy. It was concluded that local recurrence rate after primary radiation is very low and patients who may recur after primary radiation therapy , can be controlled with salvage surgery in most cases

Tumor-Cut: segmentation of brain tumors on contrast enhanced MR images for radiosurgery applications

In this paper, we present a fast and robust practical tool for segmentation of solid tumors with minimal user interaction to assist clinicians and researchers in radiosurgery planning and assessment of the response to the therapy. Particularly, a cellular automata (CA) based seeded tumor segmentation method on contrast enhanced T1 weighted magnetic resonance (MR) images, which standardizes the volume of interest (VOI) and seed selection, is proposed. First, we establish the connection of the CA-based segmentation to the graph-theoretic methods to show that the iterative CA framework solves the shortest path problem. In that regard, we modify the state transition function of the CA to calculate the exact shortest path solution. Furthermore, a sensitivity parameter is introduced to adapt to the heterogeneous tumor segmentation problem, and an implicit level set surface is evolved on a tumor probability map constructed from CA states to impose spatial smoothness. Sufficient information to initialize the algorithm is gathered from the user simply by a line drawn on the maximum diameter of the tumor, in line with the clinical practice. Furthermore, an algorithm based on CA is presented to differentiate necrotic and enhancing tumor tissue content, which gains importance for a detailed assessment of radiation therapy response. Validation studies on both clinical and synthetic brain tumor datasets demonstrate 80%-90% overlap performance of the proposed algorithm with an emphasis on less sensitivity to seed initialization, robustness with respect to different and heterogeneous tumor types, and its efficiency in terms of computation time