Estimation of the effects of normal tissue sparing using equivalent uniform dose-based optimization.

In this study, we intend to estimate the effects of normal tissue sparing between intensity modulated radiotherapy (IMRT) treatment plans generated with and without a dose volume (DV)-based physical cost function using equivalent uniform dose (EUD). Twenty prostate cancer patients were retrospectively selected for this study. For each patient, two IMRT plans were generated (i) EUD-based optimization with a DV-based physical cost function to control inhomogeneity (EUDWith DV) and (ii) EUD-based optimization without a DV-based physical cost function to allow inhomogeneity (EUDWithout DV). The generated plans were prescribed a dose of 72 Gy in 36 fractions to planning target volume (PTV). Mean dose, D30%, and D5% were evaluated for all organ at risk (OAR). Normal tissue complication probability was also calculated for all OARs using BioSuite software. The average volume of PTV for all patients was 103.02 ± 27 cm(3). The PTV mean dose for EUDWith DV plans was 73.67 ± 1.7 Gy, whereas for EUDWithout DV plans was 80.42 ± 2.7 Gy. It was found that PTV volume receiving dose more than 115% of prescription dose was negligible in EUDWith DV plans, whereas it was 28% in EUDWithout DV plans. In almost all dosimetric parameters evaluated, dose to OARs in EUDWith DV plans was higher than in EUDWithout DV plans. Allowing inhomogeneous dose (EUDWithout DV) inside the target would achieve better normal tissue sparing compared to homogenous dose distribution (EUDWith DV). Hence, this inhomogeneous dose could be intentionally dumped on the high-risk volume to achieve high local control. Therefore, it was concluded that EUD optimized plans offer added advantage of less OAR dose as well as selectively boosting dose to gross tumor volume.

Solar elastosis in conjunctival squamous cell neoplasm.

Aim: To study the role of solar elastosis in the patient's with Conjunctival Squamous Cell Neoplasia (CSCN). Materials and Methods: Paraffin embedded 30 Conjunctival Squamous Cell Neoplasia tissues were studied for the presence of solar elastosis by Verhoeff's stain. Nineteen Squamous Cell Carcinoma (SCC), 6 Carcinoma In Situ (CIS) and 5 Conjunctival Intraepithelial Neoplasia (CIN) specimens were included in the study. Disease free conjunctiva and pterygium tissues were used as negative and positive control respectively. Results: Solar elastosis was found to be present in 19 of 30 (63.3%) Conjunctival Squamous Cell neoplasia specimens. Conclusion: Our study showed the presence of solar elastosis in conjunctival squamous cell neoplasia. Poor socioeconomic condition is an important factor as most of the elastosis positive patients were farmers.

Evaluation of circulating immune complexes and serum immunoglobulins in oral cancer patients--a follow up study.

BACKGROUND: High serum immunoglobulins and circulating immune complexes (IgG, IgM, IgA and CIC) values in patients with cancer have been used as tumor markers. Hence, the aim of the study was to estimate these immunological markers in pre- and post-treatment phases with a follow-up of 3-24 months and to understand the prognostic significance of the same in patients with oral cancer. MATERIALS AND METHODS: The malignancy group consisted of 56 patients with different stages (AJCC TNM) of oral cancer and 20 healthy control group. Samples were selected at random and subjected for sequential analysis of serum biochemical markers (IgG, IgA, IgM and CIC-circulating immune complexes levels) in the pre- and post-treatment period. Statistical method employed was the paired t test. RESULTS: We observed significant elevated levels of all the immunological markers ( P < 0.01) when compared with the control group. Sequential analysis of these markers revealed significant reduction in immunological markers in stage I and II patients. On the contrary, stage III and IV patients showed remarkably elevated levels of IgA and CIC one year after initial treatment. CONCLUSIONS: All these immunological markers are indicative of tumor burden and Serum levels of CIC and IgA might be employed as prognostic indicators in oral cancer.

Mid line craniofacial defects and morning glory disc anomaly with clinical anophthalmos-a distinct clinical entity.

Morning glory syndrome (MGS) is a congenital optic disc dysplasia often associated with craniofacial anomalies, especially basal encephalocele. We report a case of a 4-month-old male baby, who was referred to our institute with the complaints of decreased vision. This is the first report from Northeastern part of India as per our knowledge.

Association between human cancer and two polymorphisms occurring together in the p21Waf1/Cip1 cyclin-dependent kinase inhibitor gene.

BACKGROUND: The cyclin-dependent kinase inhibitor gene p21Waf1/Cip1 plays a role in signaling cellular growth arrest. In response to DNA damage, p21 is induced by the p53 gene, thereby playing a direct role in mediating p53-induced G1 arrest. Alterations in this gene may adversely affect regulation of cellular proliferation and increase susceptibility for cancer. Two polymorphisms have previously been characterized in the p21 gene: a C-->A transversion at codon 31 (ser-->arg) and a C-->T transition 20 nucleotides downstream from the 3' end of exon 3. METHODS: The codon 31 polymorphism in exon 2 of the p21 gene was identified by restriction digestion (Alw26I) of products amplified by polymerase chain reaction (PCR). The polymorphism downstream from exon 3 of the p21 gene was identified by single strand conformation polymorphism (SSCP) analysis of PCR amplified products and was confirmed by PstI enzyme restriction digestion. DNA variant alleles were confirmed by direct DNA sequencing. The entire coding region and the promoter region (p53 binding domain) of the p21 gene were screened for mutations by SSCP analysis or DNA sequencing. RESULTS: The two polymorphisms were found in 18 of 96 tumor samples lacking p53 alterations (18.8%). Nine of 54 prostate adenocarcinoma samples (16.7%) contained both p21 variants, whereas 9 of 42 squamous cell carcinomas of the head and neck (21.4%) displayed both polymorphisms. Of the 110 controls examined, 10 (9.1%) had both alterations. Both p21 polymorphisms occurred together in all samples examined and there was no indication of mutation in the coding region of the p21 gene or in the p53 binding domain of the promoter region. CONCLUSIONS: These data suggest that p21 gene variants may play a role in increased susceptibility for the development of some types of cancer. In the current study, the authors demonstrated that the occurrence of these two polymorphisms is increased in prostate adenocarcinoma and squamous cell carcinoma of the head and neck. The polymorphic sites may be directly responsible for this apparent increased susceptibility or they may be linked to regulatory region alterations.

Identification of a PstI polymorphism in the p21Cip1/Waf1 cyclin-dependent kinase inhibitor gene.

A PstI polymorphism in the 3' flanking region of the p21Cip1/Waf1 cyclin-dependent kinase inhibitor gene is described. DNA sequencing analysis identified a C-->T base substitution in the 3' flanking region of the gene. This substitution leads to the destruction of a PstI site and results in a biallelic DNA polymorphism. This restriction fragment length polymorphism (RFLP) provides the first known genetic marker for this cell cycle regulatory gene.

Treatment of keloids by 90Sr-90Y beta-rays.

The use of radiations for the treatment of keloids was the topic of debate for years. Because of the benign nature of the keloids, surgery (keloidectomy) was treatment of choice. However, the use of surgery alone for arresting the keloids growth does not give satisfactory results due to the high frequency of recurrences. In this study 110 symptomatic cases were treated with 90Sr-90Y beta-radiation either alone for flat keloids or in combination with surgery for thick keloids. The results obtained with this method were found to be quite satisfactory. Patients were given four fractions of 5 Gy per fraction either as weekly or twice weekly schedules. Radiation dose of 2000 cGy given twice weekly in four fractions showed response in 86% of the cases as compared to 73% in those receiving four fractions of 5 Gy weekly. Further observations on different time dose fractionation schedules would open up newer dimensions in the radiotherapy of keloids.