Integration of radiation oncology with surgery as combined-modality treatment

Molecular MRI-Based Monitoring of Cancer Immunotherapy Treatment Response

Immunotherapy constitutes a paradigm shift in cancer treatment. Its FDA approval for several indications has yielded improved prognosis for cases where traditional therapy has shown limited efficiency. However, many patients still fail to benefit from this treatment modality, and the exact mechanisms responsible for tumor response are unknown. Noninvasive treatment monitoring is crucial for longitudinal tumor characterization and the early detection of non-responders. While various medical imaging techniques can provide a morphological picture of the lesion and its surrounding tissue, a molecular-oriented imaging approach holds the key to unraveling biological effects that occur much earlier in the immunotherapy timeline. Magnetic resonance imaging (MRI) is a highly versatile imaging modality, where the image contrast can be tailored to emphasize a particular biophysical property of interest using advanced engineering of the imaging pipeline. In this review, recent advances in molecular-MRI based cancer immunotherapy monitoring are described. Next, the presentation of the underlying physics, computational, and biological features are complemented by a critical analysis of the results obtained in preclinical and clinical studies. Finally, emerging artificial intelligence (AI)-based strategies to further distill, quantify, and interpret the image-based molecular MRI information are discussed in terms of perspectives for the future.

Postoperative complications following intraoperative radiotherapy in abdominopelvic malignancy: A single institution analysis of 113 consecutive patients

BACKGROUND

Intraoperative radiotherapy (IORT) has advantages over external beam radiation therapy (EBRT). Few studies have described side effects associated with its addition. We evaluated our institution's experience with abdominopelvic IORT to assess safety by postoperative complication rates.

METHODS

Prospectively collected IRB-approved database of all patients receiving abdominopelvic IORT (via high dose rate brachytherapy) at Johns Hopkins Hospital between November 2006 and May 2014 was reviewed. Patients were discussed in multidisciplinary conferences. Those selected for IORT were patients for whom curative intent resection was planned for which IORT could improve margin-negative resection and optimize locoregional control. Perioperative complications were classified via Clavien-Dindo scale for postoperative surgical complications.

RESULTS

A total of 113 patients were evaluated. Most common diagnosis was sarcoma (50/113, 44%) followed by colorectal cancer (45/113, 40%), most of which were recurrent (84%). There were no perioperative deaths. A total of 57% of patients experienced a complication Grade II or higher: 24% (27/113) Grade II; 27% (30/113) Grade III; 7% (8/113) Grade IV. Wound complications were most common (38%), then gastrointestinal (25%). No radiotherapy variables were significantly associated with complications on uni/multi-variate analysis.

CONCLUSIONS

Our institution's experience with IORT demonstrated historically expected postoperative complication rates. IORT is safe, with acceptable perioperative morbidity.

Intraoperative radiotherapy for gastrointestinal malignancies: contemporary outcomes with multimodality therapy

The integration of intraoperative radiotherapy (IORT) into the multimodal treatment of gastrointestinal cancer is feasible and leads to high rates of local control. In-field tumoral control using IORT-containing strategies can be achieved in over 90 % of most cases, regardless of the site or status of the tumor (primary or recurrent). Electron beam IORT, or intraoperative electron radiation therapy, is the dominant technology used in institutions reporting data in publications the 21st century. Neither surgery nor systemic therapy is compromised by the integration of IORT-containing radiotherapy.

Bibliometrics of intraoperative radiotherapy: analysis of technology, practice and publication tendencies

PURPOSE

To analyze the performance and quality of intraoperative radiation therapy (IORT) publications identified in medical databases during a recent period in terms of bibliographic metrics.

MATERIALS AND METHODS

A bibliometric search was conducted for IORT papers published in the PubMed database between 1997 and 2013. Publication rate was used as a quantity indicator; the 2012 Science Citation Index Impact Factor as a quality indicator. Furthermore, the publications were stratified in terms of study type, scientific topic reported, year of publication, tumor type and journal specialty. We performed a one-way analysis of variance (ANOVA) to determine differences between the means of the analyzed groups.

RESULTS

Among the total of 207 journals, articles were reported significantly more frequently in surgery (n = 399, 41 %) and radiotherapy journals (n = 273, 28 %; p < 0.01). The highest impact factor was achieved by clinical oncology journals (p < 0.01). The majority of identified articles were retrospective cohort reports (n = 622, 64 %), followed by review articles (n = 204, 21 %; p < 0.001). Regarding primary topic, reports on cancer outcome following specific tumor therapy were most frequently published (n = 661, 68 %; p < 0.001) and gained the highest mean impact factor (p < 0.01). Gastrointestinal tumor reports were represented most frequently (n = 456, 47 %; p < 0.001) and the mean superior impact factor was earned by breast and gynecologic publications (p < 0.01).

CONCLUSION

We identified a consistent and sustained scientific productivity of international IORT expert groups. Most publications appeared in journals with surgical and radiooncological content. The highest impact factor was achieved by medical oncology journals.

Radiolabeled Cetuximab Conjugates for EGFR Targeted Cancer Diagnostics and Therapy

The epidermal growth factor receptor (EGFR) has evolved over years into a main molecular target for the treatment of different cancer entities. In this regard, the anti-EGFR antibody cetuximab has been approved alone or in combination with: (a) chemotherapy for treatment of colorectal and head and neck squamous cell carcinoma and (b) with external radiotherapy for treatment of head and neck squamous cell carcinoma. The conjugation of radionuclides to cetuximab in combination with the specific targeting properties of this antibody might increase its therapeutic efficiency. This review article gives an overview of the preclinical studies that have been performed with radiolabeled cetuximab for imaging and/or treatment of different tumor models. A particularly promising approach seems to be the treatment with therapeutic radionuclide-labeled cetuximab in combination with external radiotherapy. Present data support an important impact of the tumor micromilieu on treatment response that needs to be further validated in patients. Another important challenge is the reduction of nonspecific uptake of the radioactive substance in metabolic organs like liver and radiosensitive organs like bone marrow and kidneys. Overall, the integration of diagnosis, treatment and monitoring as a theranostic approach appears to be a promising strategy for improvement of individualized cancer treatment.

Clinical review: surgical management of locally advanced and recurrent colorectal cancer

AIM

Recurrent and locally advanced colorectal cancers frequently require en bloc resection of involved organs to achieve negative margins. The aim of this review is to evaluate the most current literature related to the surgical management of locally advanced and recurrent colorectal cancer.

METHODS

A literature review was performed on the electronic databases MEDLINE from PubMed, EMBASE and the Cochrane library for publications in the English language from January 1993 to July 2013. The MeSH search terms 'locally advanced colorectal cancer', 'recurrent colorectal cancer' and 'surgical management' were used.

RESULTS

A total of 1,470 patients with recurrent or locally advanced primary colorectal cancer were included in 22 studies. Surgical removal of the tumour with negative margins (R0) offers the best prognosis in term of survival with a 5-year survival of up to 70 %. MVR is needed in approximately 10 % with the most commonly involved organ being the bladder. The mean post-operative morbidity is 40 %, mainly relating to superficial surgical site infection, pelvic collections and delayed wound healing. Most patients will undergo radiotherapy and/or chemotherapy pre- or post-operatively. The mean 5-year overall survival for R0 resection is 50 % for recurrent and locally advanced primary tumours while survival following R1 or R2 is 12 and <5 %, respectively.

CONCLUSION

Multimodal therapy and extended surgery to achieve clear margins offers good prognosis to patients with recurrent and locally advanced colorectal cancers.