GALLERY: Jennifer Aniston, second from left, at a screening at the Ronald Reagan Building of the Lifetime movie “Five.” At left is Patricia Clarkson; at right are Lifetime President Nancy Dubuc, Jeanne Tripplehorn, and executive producer Kristin Hahn. Click on the picture to view more photos from the event.

Can you hear it — the roar of pink? With the start of October comes annual proof of breast cancer’s dominance on the cause circuit. The always A-listy Susan G. Komen for the Cure gala at the Kennedy Center will cap off the month, but pink ribbons are already spilling out everywhere, from the NFL field — where players are already accessorized with the hue — to screen stars.

Case in point: Jennifer Aniston, who made a rare D.C. celebvocacy appearance to raise even more awareness for the disease.

Aniston, right, with Hahn, center, talking to a breast cancer patient at Inova in Alexandria. (Carolyn Kaster/AP)

On Monday, the actress spent a rainy afternoon with Jill Biden and Secretary of Health and Human Services Kathleen Sebelius touring the new Inova Breast Care Center in Alexandria, which puts breast-cancer doctors from various disciplines under the same roof.

Aniston, 42, nodded approvingly during the tour. She seemed very moved when a nurse described how difficult it is to help patients who lack insurance.

She was dressed California casual, reports our colleague Krissah Thompson — black turtleneck sweater, jeans, that chunky gold ring on her left hand that all the tabloids buzzed about last summer.

A few hours later, Aniston and Biden turned out at the Ronald Reagan Building for a reception and screening of “Five,” a Lifetime anthology of five short films about breast cancer, linked together by an oncologist (played by Jeanne Tripplehorn) who has learned cancer runs in her family.

Aniston is an executive producer of the film and directed one segment. (Other directors include Demi Moore and Alicia Keys.) For the most part, it’s very, well, Lifetimey — although the “Friends” veteran managed to mine her segment for a dark humor that feels legitimately and charmingly her own. Patricia Clarkson — who lobs her lines with a distinctly Rachel-esque zing — plays a Stage 4 cancer patient who blows through her life savings and hosts her own premature funeral.

In the house for the screening: Nancy Pelosi, Ray LaHood, Rand Paul, Scott Brown, Rosa DeLauro. (Aniston’s D.C.-bred boyfriend, actor Justin Theroux, was not in sight. **Updated, Tuesday: Theroux and Aniston sighting later that night. )

We lingered at the red carpet (neither red nor even pink, actually, but blue), hoping to ask: Why breast cancer — as opposed to, say, cervical cancer, or heart disease, or diabetes?

Clarkson (slim-fitting black skirt and top, bright red lips and nails) spoke to us of the importance of early detection, and mammograms, and hope. Tripplehorn (slim black dress, eggplant nails) made the case that a disease we seem hyper-aware of still begs for adequate research funding.

Aniston (black blazer, jeans tucked into spiky black boots) simply stood on the carpet, showered with camera flashes, and kept a distance from reporters.

Sorry, no questions.