Early Detection of Response to Radiotherapy Treatment with 11C-Acetate PET Imaging

11C-Acetate radiotracer with Positron Emission Tomography (PET) imaging is currently used in cardiovascular imaging for perfusion and oxygen consumption measurement. It is also used, among other diseases, for prostate cancer as this radiotracer does not accumulate in the bladder. The present study reports the assessment of the radiotherapy treatment by measuring the tumor perfusion and oxygenation before and at mid-treatment by imaging with dynamic 11C-Acetate in patients with head and neck cancer. A pre-treatment dynamic 11C-Acetate and a clinical static 18F-FDG PET were conducted before initiation of the treatment, and the second 11C-Acetate dynamic scan was performed after four weeks of radiotherapy (i.e., after a dose of 35 Gy for a total of 70 Gy). The two-tissue compartment model was applied to 11C-Acetate images to extract the perfusion and oxygen consumption. The results showed a reduction in tumor volume by more than 50% compared to the initial volume in patient-1. Besides, patient-2 has displayed a more reduced tumor volume after 4 weeks of treatment. The 11C-Acetate rate constant k2 representing oxygen consumption increased after radiotherapy dose in both patients. This increase of k2 could reflect the reoxygenation process inside the tumor, and it can reflect the early treatment response. In conclusion, 11C-Acetate could predict the early changes in the tumor perfusion and the oxidative metabolism to optimally adjust the treatment.

Primary and Secondary Angiosarcoma of the Breast: Report of Two Cases and Review of the Literature

Introduction: The breast's angiosarcoma is a rare entity, representing 1% of the breast's malignant neoplasms and is classified as primary and secondary; the latter is associated with radiotherapy and chronic lymphedema. Clinically both present as a voluminous and rapidly growing lesion. Surgery is the cornerstone of a treatment since it provides the most outstanding local control, whereas radiotherapy and chemotherapy have little impact on the disease. Similarly, the oncological prognosis is poor because this type of tumor has a high recurrence rate and overall, 5-year survival of only 20%. Objective: Two cases of angiosarcoma of the breast (primary and secondary) are reported, both treated in the Breast Tumor Service and a bibliographic review of the disease is presented. Materials and Methods: All breast cancer cases were reviewed in the Breast Tumor Service for two years. Results: In the first clinical case, a 61-year-old patient was presented with a 5-month-old primary angiosarcoma in the right breast, treated with modified radical mastectomy. While in the second case, the clinical history of a 76-year-old woman with secondary breast angiosarcoma is related; the patient had a history of right breast cancer, treated ten years previously with conservative surgery, sentinel node and adjuvant radiotherapy. However, the woman presented local recurrence six years later, and she was operated on with a total mastectomy. Three years later, she developed an angiosarcoma in the surgical bed that warranted a wide resection of the chest wall. Conclusion: The breast's angiosarcoma is an aggressive and rare tumor of unknown aetiology, since it has a high recurrence rate and poor survival. Its main prognostic factors are tumor volume and resection margins. Therefore, early diagnosis is essential because it allows complete resection of the lesion.

Effects of Low Dose Fractional Radiation on Chemosensitivity of Gemcitabine-Resistant Human Pancreatic Cancer SW1900/GZ Cell

Objective: To investigate whether low-dose fractionated radiation (LDFRT) could enhance gemcitabine sensitivity in drug-resistant human pancreatic cancer SW1900/GZ cell, and to further explore the underlying mechanism. Methods: Gemcitabine-resistant human pancreatic cancer SW1900 cell line (SW1900/GZ) was induced by high concentration gemcitabine intermittent shock in vitro. The cell counting kit 8 (CCK8) was used to determine SW1900/GZ cell lines. SW1900/GZ cells were divided into six groups as follows: control, LDFRT, high dose radiation (HDRT), gemcitabine (GEM), low dose fractional radiation plus gemcitabine (LDFRT+ GEM) and high dose radiation plus gemcitabine (HDRT+ GEM) groups. The rate of apoptosis was determined by flow cytometry (FCM). Protein levels of multidrug resistance gene (MDR) and multidrug resistance-related protein gene (MRP) were examined by Western blotting. Results: The results of CCK8 test showed that the half-maximal inhibitory concentration (IC50) of non-drug-resistant cell line SW1900 and drug-resistant cell line SW1990/GZ were 230.4ng/ml and 856.6ug/ml respectively. The IC50 of SW1990/GZ was 3700 times more than the former. LDFRT significantly promoted apoptosis in SW1900 cells. Moreover, in the LDFRT group, protein levels of MDR and MRP were markedly decreased. Conclusion: This study established an effective gemcitabine-resistant cell line SW1900 of human pancreatic cancer (SW1900/GZ cell line). LDFRT sensitizes resistant SW1900/GZ pancreatic cancer cell to gemcitabine through down-regulation the expression of MDR and MPR proteins.

Dismantling Fixations on Failed Fictions: A-Bomb Survivor Study Denies The Low-Dose Radiogenic Cancer Narrative

The linear no-threshold (LNT) model of low dose ionizing radiation's (LDIR) role in radiogenic cancer incidence has long served as a pseudo-scientific belief arising from evidence that has never been proven, but has been contested. One source of current evidence that favors the LNT model is the Radiation Effects Research Foundation’s (RERF) Life Span Study (LSS) cohort of Japanese atomic bomb survivors. The RERF has managed the input data, model development, and data analyses for the LSS cohort for 45 years, publishing research papers and reports updating the RERF’s progress. In recent years, the RERF has attempted to identify other cancer risk factors that may have played a role in the cancer incidence of cohort survivors, and this effort has drawn attention to the fact that many earlier years of papers and reports from the RERF have never considered these risk factors, making such publications of questionable merit. This investigation examines two recent papers from the RERF that denominate how the RERF now analyzes specific cancer incidence for cohort members, how it treats lifestyle and other risk factors for various cancers that have arisen in the cohort, and how it continues to find and assert that bomb-blast LDIR remains a distinguishable source of radiogenic cancer in the cohort. The investigation observes that the cohort input data and modeling have extensive deficiencies and defects, many having been identified by RERF authors themselves, that substantially compromise the findings of these two papers, and offers concluding evidence that the LDIR radiogenic cancer model is highly implausible if not impossible. From such evidence, a final conclusion must arise that supports a threshold model for the dose–response relationship between LDIR exposure and radiogenic cancer.

Local Recurrence in Patients with Upper Third Rectum Cancer Treated with Surgery Alone Compared with Surgery Plus Chemoradiotherapy

Background: Colorectal cancer is the third most common neoplasm in Mexico, rectal cancer is the 16th most common neoplasm [1]. Due to the different behavior and prognostic factors of locally advance disease, manage should be tailored by a multidisciplinary approach. In tumors that rise in the upper third rectum cancer scenario there are no studies comparing the oncological results of multimodal treatment vs surgery alone. Objective: To compare the disease-free survival in patients with upper third rectal cancer treated with surgery alone vs multimodal treatment. Material and Methods: We conducted a descriptive, retrospective, longitudinal study using an historical cohort. Analysis was based from the information in patient`s records from diagnosed with cancer of the upper third rectum from 2011 to 2016. All patients with diagnosis of upper third rectum cancer were set in to two groups according to the treatment modality recited: Surgery alone and neoadjuvant chemotherapy. The records of patients diagnosed with cancer of the upper third rectum were reviewed and divided into two groups: with and without neoadjuvant chemoradiotherapy, both treated with surgery. Results: A total of 64 patient`s record were eligible, 48 of them were treated with surgery alone and 16 with a multimodal approach. The mean age was 65.5 years in those treated with surgery and 69 in the multimodal management group. The most frequent procedure was anterior resection, 45 cases (70.3%) in the group treated with surgery and 12 cases (18.7%) in the multimodal group. A case of complete pathological response was reported after a follow up of two years. Conclusion: The data suggests that there are no statistically significant differences in the local recurrence and disease-free survival with the use of neoadjuvant chemoradiotherapy.

Granulocytic Sarcoma with Meningeal Leukemia. A Case Report

The case of a 63-year-old woman is presented who developed 18 years after undergoing allogenic bone marrow transplantation for chronic myeloid leukaemia a granulocytic sarcoma localised in the presacral region. Complete radiologic remission was obtained with the administration of imatinib. She developed a metachron granulocytic sarcoma in the right frontal region associated to leptomeningeal infiltration. Complete clinical and near complete radiological remission was obtained with the administration of nilotinib. The patient was finally lost of progression of the frontal and meningeal localisations 45 months after the presentation of the first presacral lesion. Throughout the follow-up no sign of systemic leukaemia was detected.

Keloids of the Lower Abdomen, Mons and Vulva: Several Case Studies Highlighting a Successful Approach to Treatment

Background: Perineal keloids can have an overwhelming impact on patients’ lives including pain, skin breakdown, infection, and interference with intercourse. There is a paucity of literature addressing the effective treatment techniques. Cases: Three case of perineal keloid treatment, with at least 13-month follow up, are presented. All patients are African American females who were recommended a treatment plan that combined surgical wide local excision and radiation therapy. All patients had aesthetically acceptable outcomes with recurrence-free results at least 13-months post procedure. Conclusions: These three cases describe the successful treatment of perineal keloids that utilize a combination of surgical excision with targeted radiotherapy. This approach can be offered to patients with recurrent keloidal masses and the presented principles can be utilized to achieve recurrence-free results. Teaching Points: 1. Readers will understand the basics of the pathophysiology of keloid formation and their effect on patients who experience them in sensitive areas such as the mons, vulva, and/or lower abdomen. 2. Readers will be able to describe and implement the described technique for management of keloids in these potentially sensitive areas.