Is Early Colonoscopy Beneficial in Patients With CT-Diagnosed Diverticulitis?

Elmi et al evaluated 402 patients with acute diverticulitis diagnosed on a contrast enhanced CT with subsequent colonoscopy.  Retrospectively, they looked at the complications of diverticulitis as markers for underlying carcinoma.   The presence of mesenteric or retroperitoneal lymph nodes and bowel obstruction were the highest risk factors for underlying colonic carcinoma (odds ratio of 23 and 24 respectively).  The presence of an abscess is also slightly associated with underlying carcinoma (odds ratio of 4).  Prior studies demonstrated that the presence of fisutulous tracts and perforation were also markers for underlying carcinoma (see link below).  This was not demonstrated on this study.

The incidence of carcinoma in this study was low at 9 cancers in the 402 patients included. 8 of the 9 cancers were diagnosed within 6 months of the initial presentation.
19% of the 402 patients had underlying colonic polyps.  The presence of "obvious" subjective enhancement was highly associated with underlying polyps or carcinoma.

Population: mean age of 63.3 (range 50-94)
Intervention: Colonoscopy post diagnosis of acute diverticulitis (retrospective analysis)
Comparison: the presence of complications associated with acute diverticulitis (obstruction, lymph nodes,  and associated lymph nodes)
Outcome: The presence of bowel obstruction and enlarged lymph nodes is highly associated with underlying carcinoma in patients with diverticulitis.

Links: Pubmed, Original article

Related literature: Is colonoscopy still mandatory after a CT diagnosis of left-sided diverticulitis: can colorectal cancer be confidently excluded?

Elmi et al (2013). American Journal of Radiology. 200: 1269-1274

Use of high technology imaging for surveillance of early stage breast cancer

This was a retrospective analysis to assess the rates of imaging use in breast cancer patients. The study makes use of SEER/Medicare data to analyse the rate of use in comparison to a control cohort. 

Use of high tech imaging was 60% higher among breast ca pts than controls. The utilisation is primarily in the 1st year after dx suggesting the imaging is mostly linked to the breast ca. The study also documents an increase into the use of CT, US, MR & Nuc Med studies in both the breast ca pts as well as the controls over the time period. 

Limitations of this study are that the 'appropriateness' of indications and the outcome/findings of the studies were not assessed. The exclusion of pts who died or had documented recurrence is also interesting, this likely reduced the utilisation rate in the population, and skews the population towards asymptomatc pts, with studies done for 'follow up malignancy'. 

As far as clinical practice, this article doesn't provide any clear guidance as to what we should be doing, but does reinforce that we should be following the ACR/ASCO top 5 lists when ordering/protocolling studies. 

PICO Analysis:

Population: 

-Medicare recipients (>65yo) 1998-2003

-Stage I-II Primary breast ca (~25000pts)

-EXCLUDED pts with documented recurrence or death.

Intervention: High technology imaging (CT, US, MR, NM) during months 13-48 post-diagnosis.

Comparison: Age-matched random sample of women.

Outcome: Utilization of high tech imaging (HTRI)

Use of high technology imaging for surveillance of early stage breast cancer

Reference: K. S. Panageas et al., Breast Cancer Res Treat (2012) 131:663–67

Links: Pubmed, Full text

Clear Cell Renal Cell Carcinoma: Discrimination from Other Renal Cell Carcinoma Subtypes and Oncocytoma at Multiphasic Multidetector CT

The use of multiphasic CT scan may assist in characterizing renal lesions, especially discriminating some subtypes of renal cell carcinoma (RCC) from oncocytoma.  Young et al demonstrated that oncocytomas have peak enhancement in the corticomedullary phase with an average density of 106 Hu.  Clear cell RCC enhancement also peaks in the corticomedullary phase, however their enhancement is higher than oncocytomas with an average of 125 Hu (p=0.045).  The accuracy for discriminating these lesions was 77%.  Chromophobe and papillary RCCs have peak enhancement in the nephrographic phase.  Their average corticomedullary enhancement is 74 Hu and 54 Hu respectively.  

PICO analysis

P- 298 lesions in 274 patients with an average age of 62 (23-87)

I- Retrospective analysis of enhancement characteristics of renal lesions on multiphasic CT

C- Biopsy, partial nephrectomy, and full nephrectomy results

O-Differentiating renal lesions: Subtypes of RCC versus oncocytomas

Radiology, Volume 267: Number 2, May 2013
Links: Pubmed, Full text