This review presents developments and applications in bioleaching and mineral biooxidation since publication of a previous mini review in 2003 (Olson et al. Appl Microbiol Biotechnol 63:249–257,
2003
...). There have been discoveries of newly identified acidophilic microorganisms that have unique characteristics for effective bioleaching of sulfidic ores and concentrates. Progress has been made in understanding and developing bioleaching of copper from primary copper sulfide minerals, chalcopyrite, covellite, and enargite. These developments point to low oxidation–reduction potential in concert with thermophilic bacteria and archaea as a potential key to the leaching of these minerals. On the commercial front, heap bioleaching of nickel has been commissioned, and the mineral biooxidation pretreatment of sulfidic-refractory gold concentrates is increasingly used on a global scale to enhance precious metal recovery. New and larger stirred-tank reactors have been constructed since the 2003 review article. One biooxidation–heap process for pretreatment of sulfidic-refractory gold ores was also commercialized. A novel reductive approach to bioleaching nickel laterite minerals has been proposed.
Colorectal cancer (CRC) is the third most common cancer worldwide and the fourth most common cause of cancer death. Predictions of the future burden of the disease inform health planners and raise ...awareness of the need for cancer control action. Data from the World Health Organization (WHO) mortality database for 1989–2016 were used to project colon and rectal cancer mortality rates and number of deaths in 42 countries up to the year 2035, using age‐period‐cohort (APC) modelling. Mortality rates for colon cancer are predicted to continue decreasing in the majority of included countries from Asia, Europe, North America and Oceania, except Latin America and Caribbean countries. Mortality rates from rectal cancer in general followed those of colon cancer, however rates are predicted to increase substantially in Costa Rica (+73.6%), Australia (+59.2%), United States (+27.8%), Ireland (+24.2%) and Canada (+24.1%). Despite heterogeneous trends in rates, the number of deaths is expected to rise in all countries for both colon and rectal cancer by 60.0% and 71.5% until 2035, respectively, due to population growth and ageing. Reductions in colon and rectal cancer mortality rates are probably due to better accessibility to early detection services and improved specialized care. The expected increase in rectal cancer mortality rates in some countries is worrisome and warrants further investigations.
What's new?
A new model predicts an overall rise in colorectal cancer deaths worldwide, as the global population ages, but mortality rates vary by cancer and by country. To guide public health professionals in planning and allocating resources, these authors calculated predictions for mortality rates through 2035 by country. Colon cancer mortality will continue decreasing in most countries studied, excepting Latin America and the Caribbean. Similarly, rectal cancer mortality will decline most places, but is predicted to rise substantially in Costa Rica, Australia, the United States, Ireland, and Canada, a worrisome trend that should be further investigated.
Context:
Initial treatments for patients with differentiated thyroid cancer are supported primarily by single-institution, retrospective studies, with limited follow-up and low event rates. We report ...updated analyses of long-term outcomes after treatment in patients with differentiated thyroid cancer.
Objective:
The objective was to examine effects of initial therapies on outcomes.
Design/Setting:
This was a prospective multi-institutional registry.
Patients:
A total of 4941 patients, median follow-up, 6 years, participated.
Intervention:
Interventions included total/near-total thyroidectomy (T/NTT), postoperative radioiodine (RAI), and thyroid hormone suppression therapy (THST).
Main Outcome Measure:
Main outcome measures were overall survival (OS) and disease-free survival using product limit and proportional hazards analyses.
Results:
Improved OS was noted in NTCTCS stage III patients who received RAI (risk ratio RR, 0.66; P = .04) and stage IV patients who received both T/NTT and RAI (RR, 0.66 and 0.70; combined P = .049). In all stages, moderate THST (TSH maintained subnormal-normal) was associated with significantly improved OS (RR stages I-IV: 0.13, 0.09, 0.13, 0.33) and disease-free survival (RR stages I-III: 0.52, 0.40, 0.18); no additional survival benefit was achieved with more aggressive THST (TSH maintained undetectable-subnormal). This remained true, even when distant metastatic disease was diagnosed during follow-up. Lower initial stage and moderate THST were independent predictors of improved OS during follow-up years 1–3.
Conclusions:
We confirm previous findings that T/NTT followed by RAI is associated with benefit in high-risk patients, but not in low-risk patients. In contrast with earlier reports, moderate THST is associated with better outcomes across all stages, and aggressive THST may not be warranted even in patients diagnosed with distant metastatic disease during follow-up. Moderate THST continued at least 3 years after diagnosis may be indicated in high-risk patients.
Surgery is the mainstay of treatment for thyroid cancer. The role for external beam radiotherapy (EBRT) as an adjuvant to surgery or as the primary therapy is established in anaplastic thyroid cancer ...but is controversial in differentiated thyroid cancer and uncertain in medullary thyroid cancer. This update reviews the recent reported success of combining EBRT with taxanes in anaplastic thyroid cancer. Also discussed are the recent reports from large single institutions that support the recommendations of the American and British Thyroid Associations on the use of EBRT in high-risk differentiated thyroid cancer. Further evidence on the role of EBRT in MTC is discussed. The important advances in the delivery of EBRT using intensity-modulated radiation and image-guided radiation that result in more accurate and potentially more effective radiation therapy with less toxicity are also discussed.
The International Cancer Benchmarking Partnership is investigating cancer survival differences between six high‐income nations using population‐based cancer registry data. Differences in overall ...survival are often explained by differences in the stage at diagnosis and stage‐specific survival. Comparing stage at diagnosis using cancer registry data is challenging because of different regional practices in defining stage, despite the existence of international staging classifications such as TNM. This paper describes how stage data may be reconciled for international analysis. Population‐based cancer registry data were collected for 2.4 million adults diagnosed with colorectal, lung, breast (women) or ovarian cancer during 1995–2007 in Australia, Canada, Denmark, Norway, Sweden and the United Kingdom. The stage data received were coded to a variety of international systems, including the TNM classification, Dukes' for colorectal cancer, FIGO for ovarian cancer, and to national “localised, regional, distant” categorisations. To optimise comparability for analysis, a rigorous and repeatable process was defined to produce a final stage variable for each patient. An algorithm was also defined to map TNM, Dukes' and FIGO to a “localised, regional, distant” categorisation. We recommend how stage data should be recorded and processed to optimise comparability in population‐based international comparisons of stage‐specific cancer outcomes. The process we describe to produce comparable stage data forms a benchmark for future research. The algorithm to convert between TNM and a “localised, regional, distant” categorisation should be valuable for international studies, until global consensus is achieved to adhere to a single staging system like TNM.
What's new?
The way in which “stage at diagnosis” is recorded differs across the world. These variations make it difficult to conduct international comparisons of survival by stage at diagnosis using population‐based data. In this study, the authors describe the differences in how cancer stage was recorded in registries from six high‐income countries for four common cancers. They also present an approach that allows different staging systems to be reconciled for use in survival analysis and they offer seven recommendations for recording protocols to improve international comparisons of cancer outcomes.
Until recently, cancer registries have only collected cancer clinical stage at diagnosis, before any therapy, and pathological stage after surgical resection, provided no treatment has been given ...before the surgery, but they have not collected stage data after neoadjuvant therapy (NAT). Because NAT is increasingly being used to treat a variety of tumors, it has become important to make the distinction between both the clinical and the pathological assessment without NAT and the assessment after NAT to avoid any misunderstanding of the significance of the clinical and pathological findings. It also is important that cancer registries collect data after NAT to assess response and effectiveness of this treatment approach on a population basis. The prefix y is used to denote stage after NAT. Currently, cancer registries of the American College of Surgeons' Commission on Cancer only partially collect y stage data, and data on the clinical response to NAT (yc or posttherapy clinical information) are not collected or recorded in a standardized fashion. In addition to NAT, nonoperative management after radiation and chemotherapy is being used with increasing frequency in rectal cancer and may be expanded to other treatment sites. Using examples from breast, rectal, and esophageal cancers, the pathological and imaging changes seen after NAT are reviewed to demonstrate appropriate staging.
The American Joint Committee on Cancer (AJCC) staging system for all cancer sites, including anal cancer, is the standard for cancer staging in the United States. The AJCC staging criteria are ...dynamic, and periodic updates are conducted to optimize AJCC staging definitions through a panel of experts charged with evaluating new evidence to implement changes. With greater availability of large data sets, the AJCC has since restructured and updated its processes, incorporating prospectively collected data to validate stage group revisions in the version 9 AJCC staging system, including anal cancer. Survival analysis using AJCC eighth edition staging guidelines revealed a lack of hierarchical order in which stage IIIA anal cancer was associated with a better prognosis than stage IIB disease, suggesting that, for anal cancer, tumor (T) category has a greater effect on survival than lymph node (N) category. Accordingly, version 9 stage groups have been appropriately adjusted to reflect contemporary long‐term outcomes. This article highlights the changes to the now published AJCC staging system for anal cancer, which: (1) redefined stage IIB as T1–T2N1M0 disease, (2) redefined stage IIIA as T3N0–N1M0 disease, and (3) eliminated stage 0 disease from its guidelines altogether.
To determine the maximally tolerated dose of sorafenib delivered before, during, and after stereotactic body radiation therapy (SBRT) in hepatocellular carinoma (HCC).
Eligible patients had locally ...advanced Child-Pugh class A HCC, showed Eastern Cooperative Oncology Group performance status 0-1, and were ineligible for standard local-regional therapies. Sorafenib was dose escalated in 2 strata: (1) low effective irradiated liver volume (veff) < 30% and (2) high veff 30%to 60%. Sorafenib (400 mg daily = dose level 1) was administered for 12 weeks, with 6 fractions SBRT delivered weeks 2 and 3, and escalation to full dose (400 mg twice daily) after 12 weeks as tolerated. Standard 3 + 3 cohorts with dose escalation of sorafenib were planned.
Sixteen patients (4 low veff, median dose 51 Gy; 12 high veff, median dose 33 Gy) were treated at 2 sorafenib dose levels. Of those patients 75% were had Barcelona Clinic Liver Cancer stage C, and 63% had main branch portal vein invasion. In the low veff stratum, no dose-limiting toxicities (DLTs) were observed in 4 patients treated with SBRT and sorafenib 400 mg. Inb the high veff stratum: 2 of 3 evaluable patients treated with sorafenib 400 mg experienced DLT (grade 3 large bowel bleed and grade 4 bowel obstruction 51 and 27 days, respectively, after SBRT). One of 6 evaluable patients at dose level -1 (200 mg once daily) experienced a grade 3 tumor rupture at week 5. Median overall survival and in-field local progression have not been reached. Worsening of Child-Pugh liver function class was seen in 6 of 12 patients in the high veff stratum.
Significant toxicity was observed in the high veff stratum, and concurrent SBRT with sorafenib is not recommended outside a clinical trial.
To describe outcomes of prospective trials of stereotactic body radiotherapy (SBRT) for hepatocellular carcinoma (HCC).
Two trials of SBRT for patients with active HCC unsuitable for standard ...locoregional therapies were conducted from 2004 to 2010. All patients had Child-Turcotte-Pugh class A disease, with at least 700 mL of non-HCC liver. The SBRT dose range was 24 to 54 Gy in six fractions. Primary end points were toxicity and local control at 1 year (LC1y), defined as no progressive disease (PD) of irradiated HCC by RECIST (Response Evaluation Criteria in Solid Tumors).
A total of 102 patients were evaluable (Trial 1, 2004 to 2007: n = 50; Trial 2, 2007 to 2010: n = 52). Underlying liver disease was hepatitis B in 38% of patients, hepatitis C in 38%, alcohol related in 25%, other in 14%, and none in 7%. Fifty-two percent received prior therapies (no prior sorafenib). TNM stage was III in 66%, and 61% had multiple lesions. Median gross tumor volume was 117.0 mL (range, 1.3 to 1,913.4 mL). Tumor vascular thrombosis (TVT) was present in 55%, and extrahepatic disease was present in 12%. LC1y was 87% (95% CI, 78% to 93%). SBRT dose (hazard ratio HR = 0.96; P = .02) and being in Trial 2 (HR = 0.38; P = .03) were associated with LC1y on univariate analysis. Toxicity ≥ grade 3 was seen in 30% of patients. In seven patients (two with TVT PD), death was possibly related to treatment (1.1 to 7.7 months after SBRT). Median overall survival was 17.0 months (95% CI, 10.4 to 21.3 months), for which only TVT (HR = 2.47; P = .01) and being in Trial 2 (HR = 0.49; P = .01) were significant on multivariate analysis.
These results provide strong rationale for studying SBRT for HCC in a randomized trial.
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