This appears to me most consistent with reactive follicular hyperplasia. Immunostains for T and B cells, if available, may help in the evaluation; I would anticipate that they would show the expected normal distribution of T and B cells.

I agree that the architecture appears normal. There is a follicular hyperplasia, a widening of the marginal zones and a monocytoid B-cell hyperplasia. Since the patient suffers from follicular lymphoma, a BCL2 stain to exclude follicular colonization should be done. A B- and a T-cell marker should be done as well, as suggested by Dr. Farhi. An IgD stain would be a nice way to look for the border between mantles and marginal zones.

Immuno images added

The findings in the Bcl-2 suggest a follicular lymphoma but the morphology / overall architecture favor a follicular hyperplasia. Since the cell turnover in the latter is generally high a Ki-67 would be very helpful.

At least some of the follicles appear colonized by BCL-2 weakly positive B-cells. The pattern is strongly suggestive of a partial involvement by follicular lymphoma. Ki-67 may additionally support the diagnosis.

Partial follicular colonization by lymphoma is possible, but may be difficult to prove by IHC. PCR of this node, or flow cytometry of a subsequent node, may be more informative. Even if a clonal population can be identified, the clinical significance of this finding, in a node only 1 x 1 cm, is unclear. What was the cause of the intestinal obstruction? This may be more pertinent to deciding the clinical approach to this patient.

The intensity of bcl2 in the "nodes" is very high normally in follicular lymphoma there is a difference in intensity from the mantle zone/reactive T cells to the neoplastic compartment. I would highly recommend to go back to the H&E in the same area to rule out a primary follicle.

CD10 seems to be negative in these nodular structures; a lot of CD5+ cells inside. Look like primary follicles, don't they? CD10-negative FL lymphoma in this setting looks a bit far-fetching.  
 
I would second the question about the obstruction nature to be completely sure.

In bcl201.jpg and bcl203.jpg as well as bcl205.jpg (left margin), there is a BCL2-positivity in structures that are definitely not primary follicles, which could not be explained by intrafollicular T-cells. I thinkt that an intense BCL2-positivity like in FL in situ is not a prerequisite in partial lymph node involvement of FL from other sites, which is the case in that patient.

I agree, that there are in addition some scattert follicles in which there could be a faint (specific?) bcl-2 staining.  
A high magnification picture of those follicles (to see, which cells are positiv) and Ki67 (which must show a decrease in FL) may help.