Objective:

To investigate the incremental value of morp

hologic features on high-resolution magnetic resonance imaging (MRI) in the diagnosis of lymph node metastasis of rectal cancer.

Methods:

A total of 155 rectal cancer patients who underwent high-resolution MRI examination before radical resection from June 2016 to December 2020 ［99 males and 56 females; average age (65.0610.17) years］ were retrospectively enrolled. Based on postoperative pathological results as the gold standard

the value of short diameter5 mm

short diameter9 mm

size combined with morphological features in the diagnosis of lymph node metastasis of rectal cancer was calculated and compared.

2

test was used for data analysis.

Results:

Postoperative pathological results showed that 60 patients had lymph node metastasis. The sensitivity

specificity and accuracy of the diagnosis of lymph node metastasis with the criteria of short diameter5 mm are 55.00% (33/60)

77.89% (74/95)

69.03% (107/155)

and 15.00% (9/60)

95.79% (91/95)

64.52% (107/155) for short diameter9 mm. Combined with morphological features

the sensitivity and accuracy were increased to 73.33% (compared with the standard of short diameter5 mm and short diameter9 mm

2

=4.385 and 41.397

P

=0.036 and 0.000)

79.35% (compared with the standard of short diameter5 mm and short diameter9 mm

2

=4.179 and 8.453

P

=0.041 and 0.004). While the specificity is 83.16% (79/95)

which is no statistical difference with the 5 mm criteria (

2

=0.839

P

=0.360)

and is reduced with the 9 mm criteria (

2

=8.047

P

=0.005). 11 and 35 cases of lymph node metastasis that weremissed by the diameter 5 mm and diameter 9 mm criteria were corrected by combining the morphological features respectively.

Conclusion:

Combining size and the morphological features of lymph nodes on high-resolution MRI can significantly improve the sensitivity and accuracy of diagnosing lymph nod

e metastasis in rectal cancer

and help a lot to correct missed cases of size criteria.